Changing FE-5650A frequency?
Hi all,
I've recently ripped some FE-5650A's out of some old equipment, but they
seem to be a custom build, here you can see they have the option just
listed as "-":
http://cambridge.m0tei.co.uk/files/IMG_20130330_232647.jpg
They seem to be single rail (15v) supply with an 800kHz output. I
wonder, does anyone know if it's possible to change its frequency? As
far as i'm aware this model doesn't have serial control.
Thanks,
Alec M0TEI
On Sun, Apr 07, 2013 at 12:41:10AM +0100, Alexander Wright wrote:
Hi all,
I've recently ripped some FE-5650A's out of some old equipment,
but they seem to be a custom build, here you can see they have
the option just listed as "-":
http://cambridge.m0tei.co.uk/files/IMG_20130330_232647.jpg
They seem to be single rail (15v) supply with an 800kHz output.
I wonder, does anyone know if it's possible to change its
frequency?
Open it up, take some nice pictures of the circuit boards
and components and I can probably tell you what might be
possible (after looking at them :).
As far as i'm aware this model doesn't have serial control.
best,
Herbert
Thanks,
Alec M0TEI
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and follow the instructions there.
Hi Alec,
You may be in luck. However, I would need some additional pictures, particularly
of the connector on the bottom, also some of the inside.
The primary physics package is a stand alone analog Rubidium frequency standard
that outputs 50.255* MHz frequency. That signal is used to drive various output
board configurations, included inside the unit, to provide a customer required
output frequency. The more recent revised units (they look the same) use a new
digital scheme that is much more of a hassle.
The one that I and a number of people are familiar with is the 5650-option-58
model whose output was a 1pps. To get the 1pps the 50.255+ MHz signal was used
to drive a Direct Digital Synthesizer (DDS) that produced 8.3+ MHz signal that
was then divided down via normal TTL dividers to produce the 1pps. The DDS is
capable of being changed to other frequencies up to about 20 MHz, however, the
filter following the DDS needs to be changed or bypassed to properly filter the
new frequency. Bypassing is the easiest method but would require using an
external filter to get rid of aliasing and spurs.
I put together a zip file of various information on FEI-5650-option 58 that will
help you get familiar with the family line. If you have problems with the link
let me know. Also, after you get a successful download let me know so I can
reduce the FTP storage level, thank you.
http://pages.suddenlink.net/stevewingate/cryptic1/for alec on 5650-option-58.zip
Bill....WB6BNQ
Alexander Wright wrote:
Hi all,
I've recently ripped some FE-5650A's out of some old equipment, but they
seem to be a custom build, here you can see they have the option just
listed as "-":
http://cambridge.m0tei.co.uk/files/IMG_20130330_232647.jpg
They seem to be single rail (15v) supply with an 800kHz output. I
wonder, does anyone know if it's possible to change its frequency? As
far as i'm aware this model doesn't have serial control.
Thanks,
Alec M0TEI
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.
Hey Bill: Thanks for the archive!!!!
Don
I put together a zip file of various information on FEI-5650-option 58
that will
help you get familiar with the family line. If you have problems with
the link
let me know. Also, after you get a successful download let me know so I
can
reduce the FTP storage level, thank you.
http://pages.suddenlink.net/stevewingate/cryptic1/for alec on
5650-option-58.zip
Bill....WB6BNQ
--
"Neither the voice of authority nor the weight of reason and argument
are as significant as experiment, for thence comes quiet to the mind."
De Erroribus Medicorum, R. Bacon, 13th century.
"If you don't know what it is, don't poke it."
Ghost in the Shell
Dr. Don Latham AJ7LL
Six Mile Systems LLP
17850 Six Mile Road
POB 134
Huson, MT, 59846
VOX 406-626-4304
www.lightningforensics.com
www.sixmilesystems.com
On 07/04/13 05:01, WB6BNQ wrote:
Hi Alec,
You may be in luck. However, I would need some additional pictures, particularly
of the connector on the bottom, also some of the inside.
Bill,
Thanks for your reply! Here are some photos of the inside:
http://m0tei.co.uk/fe5650pics/
You'll see that it comes with a custom machined plate screwed onto the
front - this was how it was mounted in the thing i pulled it out of. It
can be removed but i found it easier to take the thing apart with it on.
A thermostatic switch used to bolt onto it to (presumably) act as a
thermal cutout.
You'll also notice that the boards we're probably interested in are
potted it some sort of white compound - it's hard but crumbly - feels
like some sort of polymer foam. I've started to pick it off a bit but
could you just confirm that this is actually a sensible thing to do
before I go all out scraping it off? Thanks!
The primary physics package is a stand alone analog Rubidium frequency standard
that outputs 50.255* MHz frequency. That signal is used to drive various output
board configurations, included inside the unit, to provide a customer required
output frequency. The more recent revised units (they look the same) use a new
digital scheme that is much more of a hassle.
This unit is probably from late 1996/1997 if that helps?
The one that I and a number of people are familiar with is the 5650-option-58
model whose output was a 1pps. To get the 1pps the 50.255+ MHz signal was used
to drive a Direct Digital Synthesizer (DDS) that produced 8.3+ MHz signal that
was then divided down via normal TTL dividers to produce the 1pps. The DDS is
capable of being changed to other frequencies up to about 20 MHz, however, the
filter following the DDS needs to be changed or bypassed to properly filter the
new frequency. Bypassing is the easiest method but would require using an
external filter to get rid of aliasing and spurs.
I put together a zip file of various information on FEI-5650-option 58 that will
help you get familiar with the family line. If you have problems with the link
let me know. Also, after you get a successful download let me know so I can
reduce the FTP storage level, thank you.
http://pages.suddenlink.net/stevewingate/cryptic1/for alec on 5650-option-58.zip
Bill....WB6BNQ
Awesome, looks like there's some great info there! Unfortunately i'm not
sure hoe relevant it is to mine since my option doesn't seem to do RS232....
On 07/04/13 04:17, Herbert Poetzl wrote:
Open it up, take some nice pictures of the circuit boards
and components and I can probably tell you what might be
possible (after looking at them :).
Thanks Herbert! Pictures above^
As far as i'm aware this model doesn't have serial control.
best,
Herbert
Best regards,
Alec
On Sun, Apr 07, 2013 at 11:27:23AM +0100, Alexander Wright wrote:
On 07/04/13 05:01, WB6BNQ wrote:
Hi Alec,
You may be in luck. However, I would need some additional pictures,
particularly
of the connector on the bottom, also some of the inside.
Bill,
Thanks for your reply! Here are some photos of the inside:
http://m0tei.co.uk/fe5650pics/
You'll see that it comes with a custom machined plate screwed
onto the front - this was how it was mounted in the thing i
pulled it out of. It can be removed but i found it easier to
take the thing apart with it on. A thermostatic switch used to
bolt onto it to (presumably) act as a thermal cutout.
The baseplate (2xLM2941, LP2952) basically is the power
supply/regulation, so nothing interesting there.
You'll also notice that the boards we're probably interested
in are potted it some sort of white compound - it's hard but
crumbly - feels like some sort of polymer foam. I've started
to pick it off a bit but could you just confirm that this is
actually a sensible thing to do before I go all out scraping
it off?
The purpose of the polymer foam is isolation to keep a
stable temperature throughout the boards.
http://www.qsl.net/z/zl1bpu/PROJ/FE5650-2.jpg
The top layer in this image is the DDS board, and it is
basically identical to the FE5680A, which means it can
be adjusted in a wide range, but only does digital synthesis
based on the reference frequency.
But let's see what Bill says to the pictures ... :)
best,
Herbert
Thanks!
The primary physics package is a stand alone analog Rubidium frequency
standard
that outputs 50.255* MHz frequency. That signal is used to drive various
output
board configurations, included inside the unit, to provide a customer
required
output frequency. The more recent revised units (they look the same) use
a new
digital scheme that is much more of a hassle.
This unit is probably from late 1996/1997 if that helps?
The one that I and a number of people are familiar with is the
5650-option-58
model whose output was a 1pps. To get the 1pps the 50.255+ MHz signal was
used
to drive a Direct Digital Synthesizer (DDS) that produced 8.3+ MHz signal
that
was then divided down via normal TTL dividers to produce the 1pps. The
DDS is
capable of being changed to other frequencies up to about 20 MHz, however,
the
filter following the DDS needs to be changed or bypassed to properly
filter the
new frequency. Bypassing is the easiest method but would require using an
external filter to get rid of aliasing and spurs.
I put together a zip file of various information on FEI-5650-option 58
that will
help you get familiar with the family line. If you have problems with the
link
let me know. Also, after you get a successful download let me know so I
can
reduce the FTP storage level, thank you.
http://pages.suddenlink.net/stevewingate/cryptic1/for alec on
5650-option-58.zip
Bill....WB6BNQ
Awesome, looks like there's some great info there! Unfortunately i'm not
sure hoe relevant it is to mine since my option doesn't seem to do RS232....
On 07/04/13 04:17, Herbert Poetzl wrote:
Open it up, take some nice pictures of the circuit boards
and components and I can probably tell you what might be
possible (after looking at them :).
Thanks Herbert! Pictures above^
As far as i'm aware this model doesn't have serial control.
best,
Herbert
Best regards,
Alec
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.
On 07/04/13 15:10, Herbert Poetzl wrote:
The purpose of the polymer foam is isolation to keep a
stable temperature throughout the boards.
http://www.qsl.net/z/zl1bpu/PROJ/FE5650-2.jpg
The top layer in this image is the DDS board, and it is
basically identical to the FE5680A, which means it can
be adjusted in a wide range, but only does digital synthesis
based on the reference frequency.
But let's see what Bill says to the pictures ... :)
best,
Herbert
Herbert, the board doesn't seem to be the same, the chips which are
visible don't line up with the ones in that picture. Anyway my curiosity
got the better of me and I dug through the foam some more to find a long
row of DIP switches. I bet i can change the divider ratio with some
combination of those:
http://m0tei.co.uk/fe5650pics/IMG_20130407_170929.jpg
Also, you can see that the chip is an AD9955 DDS chip:
http://novatech-instr.com/PDF_files/AD9955.pdf
Alec
Hi Alex,
These units were used as timing references for secure communication systems (Havequick). see ebay item 130832014630. Unfortunatly they are an older design with a two chip DDS. The other problem is that the "M" designation is for military and means they have been partially encapsulated with polyurethene foam. You can cut it away but it is very easy to damage the PCB. Frequency setting is by DIP switches (under the foam) allowing full range of frequency selection. However the output filter is narrow so you can't go far from 800kHz.
Did you buy all seven?
Robert G8RPI.
From: Alexander Wright alecjw@gmail.com
To: time-nuts@febo.com
Sent: Sunday, 7 April 2013, 0:41
Subject: [time-nuts] Changing FE-5650A frequency?
Hi all,
I've recently ripped some FE-5650A's out of some old equipment, but they seem to be a custom build, here you can see they have the option just listed as "-":
http://cambridge.m0tei.co.uk/files/IMG_20130330_232647.jpg
They seem to be single rail (15v) supply with an 800kHz output. I wonder, does anyone know if it's possible to change its frequency? As far as i'm aware this model doesn't have serial control.
Thanks,
Alec M0TEI
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 Herbert,
These units are different to the picture at
http://www.qsl.net/z/zl1bpu/PROJ/FE5650-2.jpg
They have dip switches and no PIC. The option is covered in one of the manual out there but I'm sitting at the wrong computer to dig out the details.
Robert G8RPI.
From: Herbert Poetzl herbert@13thfloor.at
To: Discussion of precise time and frequency measurement time-nuts@febo.com
Sent: Sunday, 7 April 2013, 15:10
Subject: Re: [time-nuts] Changing FE-5650A frequency?
On Sun, Apr 07, 2013 at 11:27:23AM +0100, Alexander Wright wrote:
On 07/04/13 05:01, WB6BNQ wrote:
Hi Alec,
You may be in luck. However, I would need some additional pictures,
particularly
of the connector on the bottom, also some of the inside.
Bill,
Thanks for your reply! Here are some photos of the inside:
http://m0tei.co.uk/fe5650pics/
You'll see that it comes with a custom machined plate screwed
onto the front - this was how it was mounted in the thing i
pulled it out of. It can be removed but i found it easier to
take the thing apart with it on. A thermostatic switch used to
bolt onto it to (presumably) act as a thermal cutout.
The baseplate (2xLM2941, LP2952) basically is the power
supply/regulation, so nothing interesting there.
You'll also notice that the boards we're probably interested
in are potted it some sort of white compound - it's hard but
crumbly - feels like some sort of polymer foam. I've started
to pick it off a bit but could you just confirm that this is
actually a sensible thing to do before I go all out scraping
it off?
The purpose of the polymer foam is isolation to keep a
stable temperature throughout the boards.
http://www.qsl.net/z/zl1bpu/PROJ/FE5650-2.jpg
The top layer in this image is the DDS board, and it is
basically identical to the FE5680A, which means it can
be adjusted in a wide range, but only does digital synthesis
based on the reference frequency.
But let's see what Bill says to the pictures ... :)
best,
Herbert
Thanks!
The primary physics package is a stand alone analog Rubidium frequency
standard
that outputs 50.255* MHz frequency. That signal is used to drive various
output
board configurations, included inside the unit, to provide a customer
required
output frequency. The more recent revised units (they look the same) use
a new
digital scheme that is much more of a hassle.
This unit is probably from late 1996/1997 if that helps?
The one that I and a number of people are familiar with is the
5650-option-58
model whose output was a 1pps. To get the 1pps the 50.255+ MHz signal was
used
to drive a Direct Digital Synthesizer (DDS) that produced 8.3+ MHz signal
that
was then divided down via normal TTL dividers to produce the 1pps. The
DDS is
capable of being changed to other frequencies up to about 20 MHz, however,
the
filter following the DDS needs to be changed or bypassed to properly
filter the
new frequency. Bypassing is the easiest method but would require using an
external filter to get rid of aliasing and spurs.
I put together a zip file of various information on FEI-5650-option 58
that will
help you get familiar with the family line. If you have problems with the
link
let me know. Also, after you get a successful download let me know so I
can
reduce the FTP storage level, thank you.
http://pages.suddenlink.net/stevewingate/cryptic1/for alec on
5650-option-58.zip
Bill....WB6BNQ
Awesome, looks like there's some great info there! Unfortunately i'm not
sure hoe relevant it is to mine since my option doesn't seem to do RS232....
On 07/04/13 04:17, Herbert Poetzl wrote:
Open it up, take some nice pictures of the circuit boards
and components and I can probably tell you what might be
possible (after looking at them :).
Thanks Herbert! Pictures above^
As far as i'm aware this model doesn't have serial control.
best,
Herbert
Best regards,
Alec
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.
On 07/04/13 17:56, Robert Atkinson wrote:
Hi Alex,
These units were used as timing references for secure communication systems (Havequick). see ebay item 130832014630. Unfortunatly they are an older design with a two chip DDS. The other problem is that the "M" designation is for military and means they have been partially encapsulated with polyurethene foam. You can cut it away but it is very easy to damage the PCB. Frequency setting is by DIP switches (under the foam) allowing full range of frequency selection. However the output filter is narrow so you can't go far from 800kHz.
Did you buy all seven?
Robert G8RPI.
Robert,
Thanks for the info! I bought one of these wondering what they were,
took it apart and found the rubidium clock and figured it must be worth
something (more than the 15 quid he was asking) so I bought the remaining 6!
I've taken the foam off the top PCB and i've found that there's a
12.8MHz signal being produced which is then being divided down with an
800kHz logic chip. I should imagine the filter must be on the circuit
board below? I might try changing the frequency
of the DDS chip, removing the frequency divider and tinkering with the
output filter. Do you have any info on what sort of filter I should
expect to find?
Thanks,
Alec M0TEI