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Minicircuits 10% discount in December

JL
Jim Lux
Thu, Nov 27, 2014 1:55 PM

Time to stock up on those transformers, mixers, amplifiers<grin>

"Throughout the month of December, all online orders of any quantity of
any Mini-Circuits catalog model from our web store on minicircuits.com
will receive a 10% *discount!
"

Time to stock up on those transformers, mixers, amplifiers<grin> "Throughout the month of December, all online orders of any quantity of any Mini-Circuits catalog model from our web store on minicircuits.com will receive a 10% *discount! "
BC
Bob Camp
Thu, Nov 27, 2014 2:58 PM

Hi

What time (note the tie in to be on topic for the list :) will their retail location open on Thanksgiving?

Spending quality time on the auction sites can yield some pretty substantial discounts on RF transformers. The search process is not simple due to the crazy range of part numbers.

Once you have the transformer you get to decide how to handle coax grounds. In most cases the solution either creates a bunch of problems or it eliminates any benefit of transformer isolation.

Bob

Sent from my iPhone

On Nov 27, 2014, at 7:55 AM, Jim Lux jimlux@earthlink.net wrote:

Time to stock up on those transformers, mixers, amplifiers<grin>

"Throughout the month of December, all online orders of any quantity of any Mini-Circuits catalog model from our web store on minicircuits.com will receive a 10% *discount!
"


time-nuts mailing list -- time-nuts@febo.com
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and follow the instructions there.

Hi What time (note the tie in to be on topic for the list :) will their retail location open on Thanksgiving? Spending quality time on the auction sites can yield some pretty substantial discounts on RF transformers. The search process is not simple due to the crazy range of part numbers. Once you have the transformer you get to decide how to handle coax grounds. In most cases the solution either creates a bunch of problems or it eliminates any benefit of transformer isolation. Bob Sent from my iPhone > On Nov 27, 2014, at 7:55 AM, Jim Lux <jimlux@earthlink.net> wrote: > > Time to stock up on those transformers, mixers, amplifiers<grin> > > "Throughout the month of December, all online orders of any quantity of any Mini-Circuits catalog model from our web store on minicircuits.com will receive a 10% *discount! > " > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.
TS
Tim Shoppa
Thu, Nov 27, 2014 3:07 PM

For a hobbyist doing things a few at a time, what advantage is there to
buying RF transformers made by Mini-circuits etc., vs winding them using
commonly available ferrite cores/binocular cores?

If I needed to do a production run of 1000+ boards with tiny SMT
transformers, sure, no problem buying them from mini-circuits or a
distributor etc. But for hobbyist stuff seems far more flexible to wind
them onesy-twosy using not so tiny cores and windings selected for the
particular application.

Tim N3QE

On Thu, Nov 27, 2014 at 9:58 AM, Bob Camp kb8tq@n1k.org wrote:

Hi

What time (note the tie in to be on topic for the list :) will their
retail location open on Thanksgiving?

Spending quality time on the auction sites can yield some pretty
substantial discounts on RF transformers. The search process is not simple
due to the crazy range of part numbers.

Once you have the transformer you get to decide how to handle coax
grounds. In most cases the solution either creates a bunch of problems or
it eliminates any benefit of transformer isolation.

Bob

Sent from my iPhone

On Nov 27, 2014, at 7:55 AM, Jim Lux jimlux@earthlink.net wrote:

Time to stock up on those transformers, mixers, amplifiers<grin>

"Throughout the month of December, all online orders of any quantity of

any Mini-Circuits catalog model from our web store on minicircuits.com
will receive a 10% *discount!

"


time-nuts mailing list -- time-nuts@febo.com
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and follow the instructions there.


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For a hobbyist doing things a few at a time, what advantage is there to buying RF transformers made by Mini-circuits etc., vs winding them using commonly available ferrite cores/binocular cores? If I needed to do a production run of 1000+ boards with tiny SMT transformers, sure, no problem buying them from mini-circuits or a distributor etc. But for hobbyist stuff seems far more flexible to wind them onesy-twosy using not so tiny cores and windings selected for the particular application. Tim N3QE On Thu, Nov 27, 2014 at 9:58 AM, Bob Camp <kb8tq@n1k.org> wrote: > Hi > > What time (note the tie in to be on topic for the list :) will their > retail location open on Thanksgiving? > > Spending quality time on the auction sites can yield some pretty > substantial discounts on RF transformers. The search process is not simple > due to the crazy range of part numbers. > > Once you have the transformer you get to decide how to handle coax > grounds. In most cases the solution either creates a bunch of problems or > it eliminates any benefit of transformer isolation. > > Bob > > Sent from my iPhone > > > On Nov 27, 2014, at 7:55 AM, Jim Lux <jimlux@earthlink.net> wrote: > > > > Time to stock up on those transformers, mixers, amplifiers<grin> > > > > "Throughout the month of December, all online orders of any quantity of > any Mini-Circuits catalog model from our web store on minicircuits.com > will receive a 10% *discount! > > " > > _______________________________________________ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. >
BC
Bob Camp
Thu, Nov 27, 2014 3:28 PM

Hi

I believe I made that point earlier. The main complaint is the difficulty of getting the correct cores. I seem to have a few dozen bags of cores. I still go shopping for more as projects come up

Bob

Sent from my iPhone

On Nov 27, 2014, at 9:07 AM, Tim Shoppa tshoppa@gmail.com wrote:

For a hobbyist doing things a few at a time, what advantage is there to
buying RF transformers made by Mini-circuits etc., vs winding them using
commonly available ferrite cores/binocular cores?

If I needed to do a production run of 1000+ boards with tiny SMT
transformers, sure, no problem buying them from mini-circuits or a
distributor etc. But for hobbyist stuff seems far more flexible to wind
them onesy-twosy using not so tiny cores and windings selected for the
particular application.

Tim N3QE

On Thu, Nov 27, 2014 at 9:58 AM, Bob Camp kb8tq@n1k.org wrote:

Hi

What time (note the tie in to be on topic for the list :) will their
retail location open on Thanksgiving?

Spending quality time on the auction sites can yield some pretty
substantial discounts on RF transformers. The search process is not simple
due to the crazy range of part numbers.

Once you have the transformer you get to decide how to handle coax
grounds. In most cases the solution either creates a bunch of problems or
it eliminates any benefit of transformer isolation.

Bob

Sent from my iPhone

On Nov 27, 2014, at 7:55 AM, Jim Lux jimlux@earthlink.net wrote:

Time to stock up on those transformers, mixers, amplifiers<grin>

"Throughout the month of December, all online orders of any quantity of

any Mini-Circuits catalog model from our web store on minicircuits.com
will receive a 10% *discount!

"


time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to

and follow the instructions there.


time-nuts mailing list -- time-nuts@febo.com
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Hi I believe I made that point earlier. The main complaint is the difficulty of getting the correct cores. I seem to have a few dozen bags of cores. I still go shopping for more as projects come up Bob Sent from my iPhone > On Nov 27, 2014, at 9:07 AM, Tim Shoppa <tshoppa@gmail.com> wrote: > > For a hobbyist doing things a few at a time, what advantage is there to > buying RF transformers made by Mini-circuits etc., vs winding them using > commonly available ferrite cores/binocular cores? > > If I needed to do a production run of 1000+ boards with tiny SMT > transformers, sure, no problem buying them from mini-circuits or a > distributor etc. But for hobbyist stuff seems far more flexible to wind > them onesy-twosy using not so tiny cores and windings selected for the > particular application. > > Tim N3QE > >> On Thu, Nov 27, 2014 at 9:58 AM, Bob Camp <kb8tq@n1k.org> wrote: >> >> Hi >> >> What time (note the tie in to be on topic for the list :) will their >> retail location open on Thanksgiving? >> >> Spending quality time on the auction sites can yield some pretty >> substantial discounts on RF transformers. The search process is not simple >> due to the crazy range of part numbers. >> >> Once you have the transformer you get to decide how to handle coax >> grounds. In most cases the solution either creates a bunch of problems or >> it eliminates any benefit of transformer isolation. >> >> Bob >> >> Sent from my iPhone >> >>> On Nov 27, 2014, at 7:55 AM, Jim Lux <jimlux@earthlink.net> wrote: >>> >>> Time to stock up on those transformers, mixers, amplifiers<grin> >>> >>> "Throughout the month of December, all online orders of any quantity of >> any Mini-Circuits catalog model from our web store on minicircuits.com >> will receive a 10% *discount! >>> " >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.
JL
Jim Lux
Thu, Nov 27, 2014 4:58 PM

On 11/27/14, 7:07 AM, Tim Shoppa wrote:

For a hobbyist doing things a few at a time, what advantage is there to
buying RF transformers made by Mini-circuits etc., vs winding them using
commonly available ferrite cores/binocular cores?

Probably depends on the frequency ranges and such.  The commercial
transformers are very small, and probably have more consistent properties.

If I needed to do a production run of 1000+ boards with tiny SMT
transformers, sure, no problem buying them from mini-circuits or a
distributor etc. But for hobbyist stuff seems far more flexible to wind
them onesy-twosy using not so tiny cores and windings selected for the
particular application.

Sure.. it's a trade time for money situation.

OTOH, most hobby tinkerers are not going to fabricate semiconductor
devices like MMICs (although I'm sure there's a [semi-fab-nuts] list out
there for folks who have a 3" wafer line in their garage).

On 11/27/14, 7:07 AM, Tim Shoppa wrote: > For a hobbyist doing things a few at a time, what advantage is there to > buying RF transformers made by Mini-circuits etc., vs winding them using > commonly available ferrite cores/binocular cores? > Probably depends on the frequency ranges and such. The commercial transformers are very small, and probably have more consistent properties. > If I needed to do a production run of 1000+ boards with tiny SMT > transformers, sure, no problem buying them from mini-circuits or a > distributor etc. But for hobbyist stuff seems far more flexible to wind > them onesy-twosy using not so tiny cores and windings selected for the > particular application. Sure.. it's a trade time for money situation. OTOH, most hobby tinkerers are not going to fabricate semiconductor devices like MMICs (although I'm sure there's a [semi-fab-nuts] list out there for folks who have a 3" wafer line in their garage).
TS
Tim Shoppa
Thu, Nov 27, 2014 5:09 PM

On Thu, Nov 27, 2014 at 10:28 AM, Bob Camp kb8tq@n1k.org wrote:

The main complaint is the difficulty of getting the correct cores. I seem
to have a few dozen bags of cores.

The mainline distributors (Allied, Newark, Mouser, etc.)  have excellent
selection of Fair-Rite and other cores. Admittedly to a neophyte the
equivalence of Fair-Rite or Laird part numbers to an Amidon-style number
may not be evident.

Clifton labs has excellent webpages of examples and is also a good way to
find the cores sizes and materials commonly stocked at the mainline
distributors using the manufacturer's part number (often with cross-ref to
Amidon style number as a strong hint!)

Recently some here expressed concern that the mini-circuits part may
saturate with medium DC currents. Of course if you are doing a SMT
production run you don't want to use bigger cores than necessary and most
of the mini-circuits parts tend to be physically very tiny to meet this
market. But if you wind your own on bigger cores this is a non-issue.

Tim N3QE

On Thu, Nov 27, 2014 at 10:28 AM, Bob Camp <kb8tq@n1k.org> wrote: > The main complaint is the difficulty of getting the correct cores. I seem > to have a few dozen bags of cores. The mainline distributors (Allied, Newark, Mouser, etc.) have excellent selection of Fair-Rite and other cores. Admittedly to a neophyte the equivalence of Fair-Rite or Laird part numbers to an Amidon-style number may not be evident. Clifton labs has excellent webpages of examples and is also a good way to find the cores sizes and materials commonly stocked at the mainline distributors using the manufacturer's part number (often with cross-ref to Amidon style number as a strong hint!) Recently some here expressed concern that the mini-circuits part may saturate with medium DC currents. Of course if you are doing a SMT production run you don't want to use bigger cores than necessary and most of the mini-circuits parts tend to be physically very tiny to meet this market. But if you wind your own on bigger cores this is a non-issue. Tim N3QE
BC
Bob Camp
Thu, Nov 27, 2014 5:49 PM

Hi

At least last time I looked, the “easy to find” distributors had great selections of parts used for switching power supplies and EMI suppression. When you started to dig for the specialized parts for RF transformers and tuned filters, the stock was pretty thin to nonexistent. If you move from ferrite to powdered iron, the search process alway has been more difficult...

Bob

On Nov 27, 2014, at 11:09 AM, Tim Shoppa tshoppa@gmail.com wrote:

On Thu, Nov 27, 2014 at 10:28 AM, Bob Camp kb8tq@n1k.org wrote:

The main complaint is the difficulty of getting the correct cores. I seem
to have a few dozen bags of cores.

The mainline distributors (Allied, Newark, Mouser, etc.)  have excellent
selection of Fair-Rite and other cores. Admittedly to a neophyte the
equivalence of Fair-Rite or Laird part numbers to an Amidon-style number
may not be evident.

Clifton labs has excellent webpages of examples and is also a good way to
find the cores sizes and materials commonly stocked at the mainline
distributors using the manufacturer's part number (often with cross-ref to
Amidon style number as a strong hint!)

Recently some here expressed concern that the mini-circuits part may
saturate with medium DC currents. Of course if you are doing a SMT
production run you don't want to use bigger cores than necessary and most
of the mini-circuits parts tend to be physically very tiny to meet this
market. But if you wind your own on bigger cores this is a non-issue.

Tim N3QE


time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.

Hi At least last time I looked, the “easy to find” distributors had great selections of parts used for switching power supplies and EMI suppression. When you started to dig for the specialized parts for RF transformers and tuned filters, the stock was pretty thin to nonexistent. If you move from ferrite to powdered iron, the search process alway has been more difficult... Bob > On Nov 27, 2014, at 11:09 AM, Tim Shoppa <tshoppa@gmail.com> wrote: > > On Thu, Nov 27, 2014 at 10:28 AM, Bob Camp <kb8tq@n1k.org> wrote: > >> The main complaint is the difficulty of getting the correct cores. I seem >> to have a few dozen bags of cores. > > > The mainline distributors (Allied, Newark, Mouser, etc.) have excellent > selection of Fair-Rite and other cores. Admittedly to a neophyte the > equivalence of Fair-Rite or Laird part numbers to an Amidon-style number > may not be evident. > > Clifton labs has excellent webpages of examples and is also a good way to > find the cores sizes and materials commonly stocked at the mainline > distributors using the manufacturer's part number (often with cross-ref to > Amidon style number as a strong hint!) > > Recently some here expressed concern that the mini-circuits part may > saturate with medium DC currents. Of course if you are doing a SMT > production run you don't want to use bigger cores than necessary and most > of the mini-circuits parts tend to be physically very tiny to meet this > market. But if you wind your own on bigger cores this is a non-issue. > > Tim N3QE > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.
TS
Tim Shoppa
Thu, Nov 27, 2014 6:34 PM

Again I refer you to Clifton Labs website and cross-references there to the
Fair-Rite part numbers/mixes. Although the marketing largely emphasizes EMI
suppression, all the mainline distributors now offer several mixes and core
styles that are perfect for RF transformers.

Powdered iron, yeah, those are not so easily found at mainline
distributors, I end up getting them from kitsandparts.com or Amidon.

And to Jim's point... "build your own" MMIC from discrete RF transistors
(often different generations of CATV-oriented transistors - you get the
advantage that you get tune bias currents etc. for individual need) is
quite easy using parts stocked at Mouser etc. They also have these
impressive super-beefy broadband CATV distribution/isolation amplifiers.

Tim N3QE

On Thu, Nov 27, 2014 at 12:49 PM, Bob Camp kb8tq@n1k.org wrote:

Hi

At least last time I looked, the “easy to find” distributors had great
selections of parts used for switching power supplies and EMI suppression.
When you started to dig for the specialized parts for RF transformers and
tuned filters, the stock was pretty thin to nonexistent. If you move from
ferrite to powdered iron, the search process alway has been more
difficult...

Bob

On Nov 27, 2014, at 11:09 AM, Tim Shoppa tshoppa@gmail.com wrote:

On Thu, Nov 27, 2014 at 10:28 AM, Bob Camp kb8tq@n1k.org wrote:

The main complaint is the difficulty of getting the correct cores. I

seem

to have a few dozen bags of cores.

The mainline distributors (Allied, Newark, Mouser, etc.)  have excellent
selection of Fair-Rite and other cores. Admittedly to a neophyte the
equivalence of Fair-Rite or Laird part numbers to an Amidon-style number
may not be evident.

Clifton labs has excellent webpages of examples and is also a good way to
find the cores sizes and materials commonly stocked at the mainline
distributors using the manufacturer's part number (often with cross-ref

to

Amidon style number as a strong hint!)

Recently some here expressed concern that the mini-circuits part may
saturate with medium DC currents. Of course if you are doing a SMT
production run you don't want to use bigger cores than necessary and most
of the mini-circuits parts tend to be physically very tiny to meet this
market. But if you wind your own on bigger cores this is a non-issue.

Tim N3QE


time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to

and follow the instructions there.


time-nuts mailing list -- time-nuts@febo.com
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and follow the instructions there.

Again I refer you to Clifton Labs website and cross-references there to the Fair-Rite part numbers/mixes. Although the marketing largely emphasizes EMI suppression, all the mainline distributors now offer several mixes and core styles that are perfect for RF transformers. Powdered iron, yeah, those are not so easily found at mainline distributors, I end up getting them from kitsandparts.com or Amidon. And to Jim's point... "build your own" MMIC from discrete RF transistors (often different generations of CATV-oriented transistors - you get the advantage that you get tune bias currents etc. for individual need) is quite easy using parts stocked at Mouser etc. They also have these impressive super-beefy broadband CATV distribution/isolation amplifiers. Tim N3QE On Thu, Nov 27, 2014 at 12:49 PM, Bob Camp <kb8tq@n1k.org> wrote: > Hi > > At least last time I looked, the “easy to find” distributors had great > selections of parts used for switching power supplies and EMI suppression. > When you started to dig for the specialized parts for RF transformers and > tuned filters, the stock was pretty thin to nonexistent. If you move from > ferrite to powdered iron, the search process alway has been more > difficult... > > Bob > > > On Nov 27, 2014, at 11:09 AM, Tim Shoppa <tshoppa@gmail.com> wrote: > > > > On Thu, Nov 27, 2014 at 10:28 AM, Bob Camp <kb8tq@n1k.org> wrote: > > > >> The main complaint is the difficulty of getting the correct cores. I > seem > >> to have a few dozen bags of cores. > > > > > > The mainline distributors (Allied, Newark, Mouser, etc.) have excellent > > selection of Fair-Rite and other cores. Admittedly to a neophyte the > > equivalence of Fair-Rite or Laird part numbers to an Amidon-style number > > may not be evident. > > > > Clifton labs has excellent webpages of examples and is also a good way to > > find the cores sizes and materials commonly stocked at the mainline > > distributors using the manufacturer's part number (often with cross-ref > to > > Amidon style number as a strong hint!) > > > > Recently some here expressed concern that the mini-circuits part may > > saturate with medium DC currents. Of course if you are doing a SMT > > production run you don't want to use bigger cores than necessary and most > > of the mini-circuits parts tend to be physically very tiny to meet this > > market. But if you wind your own on bigger cores this is a non-issue. > > > > Tim N3QE > > _______________________________________________ > > time-nuts mailing list -- time-nuts@febo.com > > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. >
R(
Richard (Rick) Karlquist
Thu, Nov 27, 2014 6:41 PM

On 11/27/2014 7:07 AM, Tim Shoppa wrote:

For a hobbyist doing things a few at a time, what advantage is there to
buying RF transformers made by Mini-circuits etc., vs winding them using
commonly available ferrite cores/binocular cores?

If I needed to do a production run of 1000+ boards with tiny SMT
transformers, sure, no problem buying them from mini-circuits or a
distributor etc. But for hobbyist stuff seems far more flexible to wind
them onesy-twosy using not so tiny cores and windings selected for the
particular application.

Tim N3QE

You need the tiny cores to get the performance of the MiniCircuits
transformers.  You just can't get the same bandwidth using macro sized
"binocular" cores.  Now, if you don't need a lot of bandwidth, then
what you are saying could make sense.  Another issue is stray
capacitance.  Considerably lower with a tiny core.

I have spent many hours characterizing MiniCircuits transformers
beyond the data sheet specs, and dissecting them to learn how they
do it.  They really do have a lot of rocket science in them.  In
terms of the engineering I am buying (especially in a one-off
application) they are ridiculously cheap.  And I say that as a fairly
knowledgeable transformer designer in my own right.

I do keep binocular cores around for higher power transformers, and
for "emergencies" when I need a transformer "yesterday".

Rick Karlquist N6RK

On 11/27/2014 7:07 AM, Tim Shoppa wrote: > For a hobbyist doing things a few at a time, what advantage is there to > buying RF transformers made by Mini-circuits etc., vs winding them using > commonly available ferrite cores/binocular cores? > > If I needed to do a production run of 1000+ boards with tiny SMT > transformers, sure, no problem buying them from mini-circuits or a > distributor etc. But for hobbyist stuff seems far more flexible to wind > them onesy-twosy using not so tiny cores and windings selected for the > particular application. > > Tim N3QE You need the tiny cores to get the performance of the MiniCircuits transformers. You just can't get the same bandwidth using macro sized "binocular" cores. Now, if you don't need a lot of bandwidth, then what you are saying could make sense. Another issue is stray capacitance. Considerably lower with a tiny core. I have spent many hours characterizing MiniCircuits transformers beyond the data sheet specs, and dissecting them to learn how they do it. They really do have a lot of rocket science in them. In terms of the engineering I am buying (especially in a one-off application) they are ridiculously cheap. And I say that as a fairly knowledgeable transformer designer in my own right. I do keep binocular cores around for higher power transformers, and for "emergencies" when I need a transformer "yesterday". Rick Karlquist N6RK
R(
Richard (Rick) Karlquist
Thu, Nov 27, 2014 6:46 PM

On 11/27/2014 9:09 AM, Tim Shoppa wrote:

On Thu, Nov 27, 2014 at 10:28 AM, Bob Camp kb8tq@n1k.org wrote:

The main complaint is the difficulty of getting the correct cores. I seem
to have a few dozen bags of cores.

The mainline distributors (Allied, Newark, Mouser, etc.)  have excellent
selection of Fair-Rite and other cores. Admittedly to a neophyte the
equivalence of Fair-Rite or Laird part numbers to an Amidon-style number
may not be evident.

I recently needed some binocular cores for a transformer for a client.
After checking all the distributors, I had to buy 500 of them.  Minimum
quantity.  So much for one-off hobbyist projects.  The reason why I
did not use a MiniCircuits transformer for this client is that the
impedance was much less than 50 ohms.  This is one area that
MiniCircuits really does not address.

Rick Karlquist N6RK

On 11/27/2014 9:09 AM, Tim Shoppa wrote: > On Thu, Nov 27, 2014 at 10:28 AM, Bob Camp <kb8tq@n1k.org> wrote: > >> The main complaint is the difficulty of getting the correct cores. I seem >> to have a few dozen bags of cores. > > > The mainline distributors (Allied, Newark, Mouser, etc.) have excellent > selection of Fair-Rite and other cores. Admittedly to a neophyte the > equivalence of Fair-Rite or Laird part numbers to an Amidon-style number > may not be evident. I recently needed some binocular cores for a transformer for a client. After checking all the distributors, I had to buy 500 of them. Minimum quantity. So much for one-off hobbyist projects. The reason why I did not use a MiniCircuits transformer for this client is that the impedance was much less than 50 ohms. This is one area that MiniCircuits really does not address. Rick Karlquist N6RK
DJ
Didier Juges
Thu, Nov 27, 2014 7:03 PM

Another reason is reproducibility. If you or someone else wants to reproduce your design, using a well defined and available commercial part makes it much easier to achieve the same performance, particularly for RF components.

Didier KO4BB

On November 27, 2014 12:41:34 PM CST, "Richard (Rick) Karlquist" richard@karlquist.com wrote:

On 11/27/2014 7:07 AM, Tim Shoppa wrote:

For a hobbyist doing things a few at a time, what advantage is there

to

buying RF transformers made by Mini-circuits etc., vs winding them

using

commonly available ferrite cores/binocular cores?

If I needed to do a production run of 1000+ boards with tiny SMT
transformers, sure, no problem buying them from mini-circuits or a
distributor etc. But for hobbyist stuff seems far more flexible to

wind

them onesy-twosy using not so tiny cores and windings selected for

the

particular application.

Tim N3QE

You need the tiny cores to get the performance of the MiniCircuits
transformers.  You just can't get the same bandwidth using macro sized
"binocular" cores.  Now, if you don't need a lot of bandwidth, then
what you are saying could make sense.  Another issue is stray
capacitance.  Considerably lower with a tiny core.

I have spent many hours characterizing MiniCircuits transformers
beyond the data sheet specs, and dissecting them to learn how they
do it.  They really do have a lot of rocket science in them.  In
terms of the engineering I am buying (especially in a one-off
application) they are ridiculously cheap.  And I say that as a fairly
knowledgeable transformer designer in my own right.

I do keep binocular cores around for higher power transformers, and
for "emergencies" when I need a transformer "yesterday".

Rick Karlquist N6RK


time-nuts mailing list -- time-nuts@febo.com
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Another reason is reproducibility. If you or someone else wants to reproduce your design, using a well defined and available commercial part makes it much easier to achieve the same performance, particularly for RF components. Didier KO4BB On November 27, 2014 12:41:34 PM CST, "Richard (Rick) Karlquist" <richard@karlquist.com> wrote: > > >On 11/27/2014 7:07 AM, Tim Shoppa wrote: >> For a hobbyist doing things a few at a time, what advantage is there >to >> buying RF transformers made by Mini-circuits etc., vs winding them >using >> commonly available ferrite cores/binocular cores? >> >> If I needed to do a production run of 1000+ boards with tiny SMT >> transformers, sure, no problem buying them from mini-circuits or a >> distributor etc. But for hobbyist stuff seems far more flexible to >wind >> them onesy-twosy using not so tiny cores and windings selected for >the >> particular application. >> >> Tim N3QE > >You need the tiny cores to get the performance of the MiniCircuits >transformers. You just can't get the same bandwidth using macro sized >"binocular" cores. Now, if you don't need a lot of bandwidth, then >what you are saying could make sense. Another issue is stray >capacitance. Considerably lower with a tiny core. > >I have spent many hours characterizing MiniCircuits transformers >beyond the data sheet specs, and dissecting them to learn how they >do it. They really do have a lot of rocket science in them. In >terms of the engineering I am buying (especially in a one-off >application) they are ridiculously cheap. And I say that as a fairly >knowledgeable transformer designer in my own right. > >I do keep binocular cores around for higher power transformers, and >for "emergencies" when I need a transformer "yesterday". > >Rick Karlquist N6RK >_______________________________________________ >time-nuts mailing list -- time-nuts@febo.com >To unsubscribe, go to >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. -- Sent from my Motorola Droid Razr HD 4G LTE wireless tracker while I do other things.
JS
Jim Sanford
Thu, Nov 27, 2014 7:58 PM

YES!
That's exactly why I go to Mini-Circuits.
Jim

On 11/27/2014 2:03 PM, Didier Juges wrote:

Another reason is reproducibility. If you or someone else wants to reproduce your design, using a well defined and available commercial part makes it much easier to achieve the same performance, particularly for RF components.

Didier KO4BB

On November 27, 2014 12:41:34 PM CST, "Richard (Rick) Karlquist" richard@karlquist.com wrote:

On 11/27/2014 7:07 AM, Tim Shoppa wrote:

For a hobbyist doing things a few at a time, what advantage is there

to

buying RF transformers made by Mini-circuits etc., vs winding them

using

commonly available ferrite cores/binocular cores?

If I needed to do a production run of 1000+ boards with tiny SMT
transformers, sure, no problem buying them from mini-circuits or a
distributor etc. But for hobbyist stuff seems far more flexible to

wind

them onesy-twosy using not so tiny cores and windings selected for

the

particular application.

Tim N3QE

You need the tiny cores to get the performance of the MiniCircuits
transformers.  You just can't get the same bandwidth using macro sized
"binocular" cores.  Now, if you don't need a lot of bandwidth, then
what you are saying could make sense.  Another issue is stray
capacitance.  Considerably lower with a tiny core.

I have spent many hours characterizing MiniCircuits transformers
beyond the data sheet specs, and dissecting them to learn how they
do it.  They really do have a lot of rocket science in them.  In
terms of the engineering I am buying (especially in a one-off
application) they are ridiculously cheap.  And I say that as a fairly
knowledgeable transformer designer in my own right.

I do keep binocular cores around for higher power transformers, and
for "emergencies" when I need a transformer "yesterday".

Rick Karlquist N6RK


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YES! That's exactly why I go to Mini-Circuits. Jim On 11/27/2014 2:03 PM, Didier Juges wrote: > Another reason is reproducibility. If you or someone else wants to reproduce your design, using a well defined and available commercial part makes it much easier to achieve the same performance, particularly for RF components. > > Didier KO4BB > > > On November 27, 2014 12:41:34 PM CST, "Richard (Rick) Karlquist" <richard@karlquist.com> wrote: >> >> On 11/27/2014 7:07 AM, Tim Shoppa wrote: >>> For a hobbyist doing things a few at a time, what advantage is there >> to >>> buying RF transformers made by Mini-circuits etc., vs winding them >> using >>> commonly available ferrite cores/binocular cores? >>> >>> If I needed to do a production run of 1000+ boards with tiny SMT >>> transformers, sure, no problem buying them from mini-circuits or a >>> distributor etc. But for hobbyist stuff seems far more flexible to >> wind >>> them onesy-twosy using not so tiny cores and windings selected for >> the >>> particular application. >>> >>> Tim N3QE >> You need the tiny cores to get the performance of the MiniCircuits >> transformers. You just can't get the same bandwidth using macro sized >> "binocular" cores. Now, if you don't need a lot of bandwidth, then >> what you are saying could make sense. Another issue is stray >> capacitance. Considerably lower with a tiny core. >> >> I have spent many hours characterizing MiniCircuits transformers >> beyond the data sheet specs, and dissecting them to learn how they >> do it. They really do have a lot of rocket science in them. In >> terms of the engineering I am buying (especially in a one-off >> application) they are ridiculously cheap. And I say that as a fairly >> knowledgeable transformer designer in my own right. >> >> I do keep binocular cores around for higher power transformers, and >> for "emergencies" when I need a transformer "yesterday". >> >> Rick Karlquist N6RK >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. --- This email has been checked for viruses by Avast antivirus software. http://www.avast.com
R(
Richard (Rick) Karlquist
Thu, Nov 27, 2014 8:41 PM

On 11/27/2014 11:03 AM, Didier Juges wrote:

Another reason is reproducibility. If you or someone else wants

to reproduce your design, using a well defined and available

commercial part makes it much easier to achieve the same

performance, particularly for RF components.

Didier KO4BB

Exactly right.

I wrote an article on receiving loops and showed a design
with a 50:5 (turns ratio) transformer wound on a toroid.
Again, this is not available from MiniCircuits.  I have
wasted time dealing with numerous dumb questions about
"can I use XXX core that I have laying around the lab?"
or can I use a different gauge wire to wind it, etc.
So many people complained about the shipping cost to
buy one core that I stocked the cores and included them
with PC boards I was already selling to reduce the shipping
cost to "zero".

BTW, 73 material would NOT work in this application.
I was asked about that multiple times even though the
article specifically said it would not work and explained
why.

Rick Karlquist N6RK

On 11/27/2014 11:03 AM, Didier Juges wrote: > Another reason is reproducibility. If you or someone else wants to reproduce your design, using a well defined and available commercial part makes it much easier to achieve the same performance, particularly for RF components. > > Didier KO4BB Exactly right. I wrote an article on receiving loops and showed a design with a 50:5 (turns ratio) transformer wound on a toroid. Again, this is not available from MiniCircuits. I have wasted time dealing with numerous dumb questions about "can I use XXX core that I have laying around the lab?" or can I use a different gauge wire to wind it, etc. So many people complained about the shipping cost to buy one core that I stocked the cores and included them with PC boards I was already selling to reduce the shipping cost to "zero". BTW, 73 material would NOT work in this application. I was asked about that multiple times even though the article specifically said it would not work and explained why. Rick Karlquist N6RK
DL
Don Latham
Thu, Nov 27, 2014 8:46 PM

As the things I want to do become more complex, and time gets more precious, I have adopted the mantra “buy the biggest piece you can. . .”
Don

On Nov 27, 2014, at 1:41 PM, Richard (Rick) Karlquist richard@karlquist.com wrote:

On 11/27/2014 11:03 AM, Didier Juges wrote:

Another reason is reproducibility. If you or someone else wants

to reproduce your design, using a well defined and available

commercial part makes it much easier to achieve the same

performance, particularly for RF components.

Didier KO4BB

Exactly right.

I wrote an article on receiving loops and showed a design
with a 50:5 (turns ratio) transformer wound on a toroid.
Again, this is not available from MiniCircuits.  I have
wasted time dealing with numerous dumb questions about
"can I use XXX core that I have laying around the lab?"
or can I use a different gauge wire to wind it, etc.
So many people complained about the shipping cost to
buy one core that I stocked the cores and included them
with PC boards I was already selling to reduce the shipping
cost to "zero".

BTW, 73 material would NOT work in this application.
I was asked about that multiple times even though the
article specifically said it would not work and explained
why.

Rick Karlquist N6RK


time-nuts mailing list -- time-nuts@febo.com
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and follow the instructions there.

As the things I want to do become more complex, and time gets more precious, I have adopted the mantra “buy the biggest piece you can. . .” Don > On Nov 27, 2014, at 1:41 PM, Richard (Rick) Karlquist <richard@karlquist.com> wrote: > > > > On 11/27/2014 11:03 AM, Didier Juges wrote: >> Another reason is reproducibility. If you or someone else wants > > to reproduce your design, using a well defined and available > > commercial part makes it much easier to achieve the same > > performance, particularly for RF components. >> >> Didier KO4BB > > Exactly right. > > I wrote an article on receiving loops and showed a design > with a 50:5 (turns ratio) transformer wound on a toroid. > Again, this is not available from MiniCircuits. I have > wasted time dealing with numerous dumb questions about > "can I use XXX core that I have laying around the lab?" > or can I use a different gauge wire to wind it, etc. > So many people complained about the shipping cost to > buy one core that I stocked the cores and included them > with PC boards I was already selling to reduce the shipping > cost to "zero". > > BTW, 73 material would NOT work in this application. > I was asked about that multiple times even though the > article specifically said it would not work and explained > why. > > Rick Karlquist N6RK > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. >
JG
Joseph Gray
Thu, Nov 27, 2014 10:21 PM

Mouser carries a selection from Fair-Rite. They don't make it easy to
find a specific part number, however.

http://www.mouser.com/Fair-Rite/Passive-Components/EMI-RFI-Components/EMI-RFI-Suppressors-Ferrites/Ferrite-Toroids-Ferrite-Rings/_/N-bw7t9?P=1z13m3cZ1yxh9di

Joe Gray
W5JG

On Thu, Nov 27, 2014 at 11:34 AM, Tim Shoppa tshoppa@gmail.com wrote:

Again I refer you to Clifton Labs website and cross-references there to the
Fair-Rite part numbers/mixes. Although the marketing largely emphasizes EMI
suppression, all the mainline distributors now offer several mixes and core
styles that are perfect for RF transformers.

Powdered iron, yeah, those are not so easily found at mainline
distributors, I end up getting them from kitsandparts.com or Amidon.

And to Jim's point... "build your own" MMIC from discrete RF transistors
(often different generations of CATV-oriented transistors - you get the
advantage that you get tune bias currents etc. for individual need) is
quite easy using parts stocked at Mouser etc. They also have these
impressive super-beefy broadband CATV distribution/isolation amplifiers.

Tim N3QE

On Thu, Nov 27, 2014 at 12:49 PM, Bob Camp kb8tq@n1k.org wrote:

Hi

At least last time I looked, the "easy to find" distributors had great
selections of parts used for switching power supplies and EMI suppression.
When you started to dig for the specialized parts for RF transformers and
tuned filters, the stock was pretty thin to nonexistent. If you move from
ferrite to powdered iron, the search process alway has been more
difficult...

Bob

On Nov 27, 2014, at 11:09 AM, Tim Shoppa tshoppa@gmail.com wrote:

On Thu, Nov 27, 2014 at 10:28 AM, Bob Camp kb8tq@n1k.org wrote:

The main complaint is the difficulty of getting the correct cores. I

seem

to have a few dozen bags of cores.

The mainline distributors (Allied, Newark, Mouser, etc.)  have excellent
selection of Fair-Rite and other cores. Admittedly to a neophyte the
equivalence of Fair-Rite or Laird part numbers to an Amidon-style number
may not be evident.

Clifton labs has excellent webpages of examples and is also a good way to
find the cores sizes and materials commonly stocked at the mainline
distributors using the manufacturer's part number (often with cross-ref

to

Amidon style number as a strong hint!)

Recently some here expressed concern that the mini-circuits part may
saturate with medium DC currents. Of course if you are doing a SMT
production run you don't want to use bigger cores than necessary and most
of the mini-circuits parts tend to be physically very tiny to meet this
market. But if you wind your own on bigger cores this is a non-issue.

Tim N3QE


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Mouser carries a selection from Fair-Rite. They don't make it easy to find a specific part number, however. http://www.mouser.com/Fair-Rite/Passive-Components/EMI-RFI-Components/EMI-RFI-Suppressors-Ferrites/Ferrite-Toroids-Ferrite-Rings/_/N-bw7t9?P=1z13m3cZ1yxh9di Joe Gray W5JG On Thu, Nov 27, 2014 at 11:34 AM, Tim Shoppa <tshoppa@gmail.com> wrote: > Again I refer you to Clifton Labs website and cross-references there to the > Fair-Rite part numbers/mixes. Although the marketing largely emphasizes EMI > suppression, all the mainline distributors now offer several mixes and core > styles that are perfect for RF transformers. > > Powdered iron, yeah, those are not so easily found at mainline > distributors, I end up getting them from kitsandparts.com or Amidon. > > And to Jim's point... "build your own" MMIC from discrete RF transistors > (often different generations of CATV-oriented transistors - you get the > advantage that you get tune bias currents etc. for individual need) is > quite easy using parts stocked at Mouser etc. They also have these > impressive super-beefy broadband CATV distribution/isolation amplifiers. > > Tim N3QE > > On Thu, Nov 27, 2014 at 12:49 PM, Bob Camp <kb8tq@n1k.org> wrote: > >> Hi >> >> At least last time I looked, the "easy to find" distributors had great >> selections of parts used for switching power supplies and EMI suppression. >> When you started to dig for the specialized parts for RF transformers and >> tuned filters, the stock was pretty thin to nonexistent. If you move from >> ferrite to powdered iron, the search process alway has been more >> difficult... >> >> Bob >> >> > On Nov 27, 2014, at 11:09 AM, Tim Shoppa <tshoppa@gmail.com> wrote: >> > >> > On Thu, Nov 27, 2014 at 10:28 AM, Bob Camp <kb8tq@n1k.org> wrote: >> > >> >> The main complaint is the difficulty of getting the correct cores. I >> seem >> >> to have a few dozen bags of cores. >> > >> > >> > The mainline distributors (Allied, Newark, Mouser, etc.) have excellent >> > selection of Fair-Rite and other cores. Admittedly to a neophyte the >> > equivalence of Fair-Rite or Laird part numbers to an Amidon-style number >> > may not be evident. >> > >> > Clifton labs has excellent webpages of examples and is also a good way to >> > find the cores sizes and materials commonly stocked at the mainline >> > distributors using the manufacturer's part number (often with cross-ref >> to >> > Amidon style number as a strong hint!) >> > >> > Recently some here expressed concern that the mini-circuits part may >> > saturate with medium DC currents. Of course if you are doing a SMT >> > production run you don't want to use bigger cores than necessary and most >> > of the mini-circuits parts tend to be physically very tiny to meet this >> > market. But if you wind your own on bigger cores this is a non-issue. >> > >> > Tim N3QE >> > _______________________________________________ >> > time-nuts mailing list -- time-nuts@febo.com >> > To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> > and follow the instructions there. >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. >
BC
Bob Camp
Thu, Nov 27, 2014 10:30 PM

Hi

Finding the RF transformer parts is still a bit of a challenge.

Bob

On Nov 27, 2014, at 4:21 PM, Joseph Gray jgray@zianet.com wrote:

Mouser carries a selection from Fair-Rite. They don't make it easy to
find a specific part number, however.

http://www.mouser.com/Fair-Rite/Passive-Components/EMI-RFI-Components/EMI-RFI-Suppressors-Ferrites/Ferrite-Toroids-Ferrite-Rings/_/N-bw7t9?P=1z13m3cZ1yxh9di

Joe Gray
W5JG

On Thu, Nov 27, 2014 at 11:34 AM, Tim Shoppa tshoppa@gmail.com wrote:

Again I refer you to Clifton Labs website and cross-references there to the
Fair-Rite part numbers/mixes. Although the marketing largely emphasizes EMI
suppression, all the mainline distributors now offer several mixes and core
styles that are perfect for RF transformers.

Powdered iron, yeah, those are not so easily found at mainline
distributors, I end up getting them from kitsandparts.com or Amidon.

And to Jim's point... "build your own" MMIC from discrete RF transistors
(often different generations of CATV-oriented transistors - you get the
advantage that you get tune bias currents etc. for individual need) is
quite easy using parts stocked at Mouser etc. They also have these
impressive super-beefy broadband CATV distribution/isolation amplifiers.

Tim N3QE

On Thu, Nov 27, 2014 at 12:49 PM, Bob Camp kb8tq@n1k.org wrote:

Hi

At least last time I looked, the "easy to find" distributors had great
selections of parts used for switching power supplies and EMI suppression.
When you started to dig for the specialized parts for RF transformers and
tuned filters, the stock was pretty thin to nonexistent. If you move from
ferrite to powdered iron, the search process alway has been more
difficult...

Bob

On Nov 27, 2014, at 11:09 AM, Tim Shoppa tshoppa@gmail.com wrote:

On Thu, Nov 27, 2014 at 10:28 AM, Bob Camp kb8tq@n1k.org wrote:

The main complaint is the difficulty of getting the correct cores. I

seem

to have a few dozen bags of cores.

The mainline distributors (Allied, Newark, Mouser, etc.)  have excellent
selection of Fair-Rite and other cores. Admittedly to a neophyte the
equivalence of Fair-Rite or Laird part numbers to an Amidon-style number
may not be evident.

Clifton labs has excellent webpages of examples and is also a good way to
find the cores sizes and materials commonly stocked at the mainline
distributors using the manufacturer's part number (often with cross-ref

to

Amidon style number as a strong hint!)

Recently some here expressed concern that the mini-circuits part may
saturate with medium DC currents. Of course if you are doing a SMT
production run you don't want to use bigger cores than necessary and most
of the mini-circuits parts tend to be physically very tiny to meet this
market. But if you wind your own on bigger cores this is a non-issue.

Tim N3QE


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and follow the instructions there.


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and follow the instructions there.

Hi Finding the RF transformer parts is still a bit of a challenge. Bob > On Nov 27, 2014, at 4:21 PM, Joseph Gray <jgray@zianet.com> wrote: > > Mouser carries a selection from Fair-Rite. They don't make it easy to > find a specific part number, however. > > http://www.mouser.com/Fair-Rite/Passive-Components/EMI-RFI-Components/EMI-RFI-Suppressors-Ferrites/Ferrite-Toroids-Ferrite-Rings/_/N-bw7t9?P=1z13m3cZ1yxh9di > > Joe Gray > W5JG > > > On Thu, Nov 27, 2014 at 11:34 AM, Tim Shoppa <tshoppa@gmail.com> wrote: >> Again I refer you to Clifton Labs website and cross-references there to the >> Fair-Rite part numbers/mixes. Although the marketing largely emphasizes EMI >> suppression, all the mainline distributors now offer several mixes and core >> styles that are perfect for RF transformers. >> >> Powdered iron, yeah, those are not so easily found at mainline >> distributors, I end up getting them from kitsandparts.com or Amidon. >> >> And to Jim's point... "build your own" MMIC from discrete RF transistors >> (often different generations of CATV-oriented transistors - you get the >> advantage that you get tune bias currents etc. for individual need) is >> quite easy using parts stocked at Mouser etc. They also have these >> impressive super-beefy broadband CATV distribution/isolation amplifiers. >> >> Tim N3QE >> >> On Thu, Nov 27, 2014 at 12:49 PM, Bob Camp <kb8tq@n1k.org> wrote: >> >>> Hi >>> >>> At least last time I looked, the "easy to find" distributors had great >>> selections of parts used for switching power supplies and EMI suppression. >>> When you started to dig for the specialized parts for RF transformers and >>> tuned filters, the stock was pretty thin to nonexistent. If you move from >>> ferrite to powdered iron, the search process alway has been more >>> difficult... >>> >>> Bob >>> >>>> On Nov 27, 2014, at 11:09 AM, Tim Shoppa <tshoppa@gmail.com> wrote: >>>> >>>> On Thu, Nov 27, 2014 at 10:28 AM, Bob Camp <kb8tq@n1k.org> wrote: >>>> >>>>> The main complaint is the difficulty of getting the correct cores. I >>> seem >>>>> to have a few dozen bags of cores. >>>> >>>> >>>> The mainline distributors (Allied, Newark, Mouser, etc.) have excellent >>>> selection of Fair-Rite and other cores. Admittedly to a neophyte the >>>> equivalence of Fair-Rite or Laird part numbers to an Amidon-style number >>>> may not be evident. >>>> >>>> Clifton labs has excellent webpages of examples and is also a good way to >>>> find the cores sizes and materials commonly stocked at the mainline >>>> distributors using the manufacturer's part number (often with cross-ref >>> to >>>> Amidon style number as a strong hint!) >>>> >>>> Recently some here expressed concern that the mini-circuits part may >>>> saturate with medium DC currents. Of course if you are doing a SMT >>>> production run you don't want to use bigger cores than necessary and most >>>> of the mini-circuits parts tend to be physically very tiny to meet this >>>> market. But if you wind your own on bigger cores this is a non-issue. >>>> >>>> Tim N3QE >>>> _______________________________________________ >>>> time-nuts mailing list -- time-nuts@febo.com >>>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>> and follow the instructions there. >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.
GH
Gerhard Hoffmann
Thu, Nov 27, 2014 11:10 PM

Am 27.11.2014 um 23:30 schrieb Bob Camp:

Hi

Finding the RF transformer parts is still a bit of a challenge.

No. These work quite good for me:

CX2074  4:1 CT
CX2147  1:1 CT

<
http://www.digikey.de/product-search/de/rf-if-and-rfid/balun/3539019?k=cx2074

The 1:1 is optimum for the NIST doubler at the sources, btw.
The 4:1 as an autotransformer 9:1 at the drains. (2*BF862).
Gives you 13 dBm @ 2f for 13 dBm in at 1f upto 40 MHz in.

Still searching a good balun xformer for 800 MHz in.--> 1600 out.

regards, Gerhard

Am 27.11.2014 um 23:30 schrieb Bob Camp: > Hi > > Finding the RF transformer parts is still a bit of a challenge. No. These work quite good for me: CX2074 4:1 CT CX2147 1:1 CT < http://www.digikey.de/product-search/de/rf-if-and-rfid/balun/3539019?k=cx2074 > The 1:1 is optimum for the NIST doubler at the sources, btw. The 4:1 as an autotransformer 9:1 at the drains. (2*BF862). Gives you 13 dBm @ 2f for 13 dBm in at 1f upto 40 MHz in. Still searching a good balun xformer for 800 MHz in.--> 1600 out. regards, Gerhard
BC
Bob Camp
Thu, Nov 27, 2014 11:54 PM

Hi

On Nov 27, 2014, at 5:10 PM, Gerhard Hoffmann dk4xp@arcor.de wrote:

Am 27.11.2014 um 23:30 schrieb Bob Camp:

Hi

Finding the RF transformer parts is still a bit of a challenge.

No. These work quite good for me:

CX2074  4:1 CT
CX2147  1:1 CT

To get back to the original post:

Which Fair-Rite cores listed on Mouser can be used for making transformers?

There are a variety of people making pre-wound parts.

Bob

< http://www.digikey.de/product-search/de/rf-if-and-rfid/balun/3539019?k=cx2074 >

The 1:1 is optimum for the NIST doubler at the sources, btw.
The 4:1 as an autotransformer 9:1 at the drains. (2*BF862).
Gives you 13 dBm @ 2f for 13 dBm in at 1f upto 40 MHz in.

Still searching a good balun xformer for 800 MHz in.--> 1600 out.

regards, Gerhard


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Hi > On Nov 27, 2014, at 5:10 PM, Gerhard Hoffmann <dk4xp@arcor.de> wrote: > > Am 27.11.2014 um 23:30 schrieb Bob Camp: >> Hi >> >> Finding the RF transformer parts is still a bit of a challenge. > > No. These work quite good for me: > > CX2074 4:1 CT > CX2147 1:1 CT To get back to the original post: Which Fair-Rite cores listed on Mouser can be used for making transformers? There are a variety of people making pre-wound parts. Bob > > < http://www.digikey.de/product-search/de/rf-if-and-rfid/balun/3539019?k=cx2074 > > > The 1:1 is optimum for the NIST doubler at the sources, btw. > The 4:1 as an autotransformer 9:1 at the drains. (2*BF862). > Gives you 13 dBm @ 2f for 13 dBm in at 1f upto 40 MHz in. > > Still searching a good balun xformer for 800 MHz in.--> 1600 out. > > regards, Gerhard > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.
JL
Jim Lux
Thu, Nov 27, 2014 11:59 PM

On 11/27/14, 3:10 PM, Gerhard Hoffmann wrote:

Am 27.11.2014 um 23:30 schrieb Bob Camp:

Hi

Finding the RF transformer parts is still a bit of a challenge.

No. These work quite good for me:

CX2074  4:1 CT
CX2147  1:1 CT

<
http://www.digikey.de/product-search/de/rf-if-and-rfid/balun/3539019?k=cx2074

The 1:1 is optimum for the NIST doubler at the sources, btw.
The 4:1 as an autotransformer 9:1 at the drains. (2*BF862).
Gives you 13 dBm @ 2f for 13 dBm in at 1f upto 40 MHz in.

Still searching a good balun xformer for 800 MHz in.--> 1600 out.

Analog Devices seems to use these for their various application circuits
Up to 3 GHz is the Mini-Circuits TC1-1-13.
From 3 GHz to 4 GHz is the Johanson Technology
3600BL14M050.
From 4.9 GHz to 6 GHz is the Johanson Technology
5400BL15B050.

On 11/27/14, 3:10 PM, Gerhard Hoffmann wrote: > Am 27.11.2014 um 23:30 schrieb Bob Camp: >> Hi >> >> Finding the RF transformer parts is still a bit of a challenge. > > No. These work quite good for me: > > CX2074 4:1 CT > CX2147 1:1 CT > > < > http://www.digikey.de/product-search/de/rf-if-and-rfid/balun/3539019?k=cx2074 > > > > The 1:1 is optimum for the NIST doubler at the sources, btw. > The 4:1 as an autotransformer 9:1 at the drains. (2*BF862). > Gives you 13 dBm @ 2f for 13 dBm in at 1f upto 40 MHz in. > > Still searching a good balun xformer for 800 MHz in.--> 1600 out. > Analog Devices seems to use these for their various application circuits Up to 3 GHz is the Mini-Circuits TC1-1-13. From 3 GHz to 4 GHz is the Johanson Technology 3600BL14M050. From 4.9 GHz to 6 GHz is the Johanson Technology 5400BL15B050.
TS
Tim Shoppa
Fri, Nov 28, 2014 12:17 AM

43 binocular core: 2843002402, 14 cents qty 1 at Mouser.

77 binocular core: 2873000202, 59 cents qty 1 at Newark.

43 material toroid: 5943000201, 12 cents qty 1 at Mouser.

Clifton Labs has good examples and measurements on transformers wound on
these and other cores.

On Thu, Nov 27, 2014 at 6:54 PM, Bob Camp kb8tq@n1k.org wrote:

To get back to the original post:

Which Fair-Rite cores listed on Mouser can be used for making transformers?

43 binocular core: 2843002402, 14 cents qty 1 at Mouser. 77 binocular core: 2873000202, 59 cents qty 1 at Newark. 43 material toroid: 5943000201, 12 cents qty 1 at Mouser. Clifton Labs has good examples and measurements on transformers wound on these and other cores. On Thu, Nov 27, 2014 at 6:54 PM, Bob Camp <kb8tq@n1k.org> wrote: > To get back to the original post: > > Which Fair-Rite cores listed on Mouser can be used for making transformers? >