L
Lifespeed
Fri, Jan 10, 2020 1:38 AM
Hi Time Nuts,
I have a need for a low phase noise, noise floor and noise figure amplifier
at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the best of
which degrades phase noise by a couple dB. I'm working with a signal with
-172dBc/Hz PN, so not much tolerance for degradation here. The input signal
level is only 3dBm, so noise figure still matters as well. I'm looking for
15dB gain, 16dBm P1. The residual phase noise would have to be better than
-180dBc/Hz, and I would probably operate the amplifier slightly compressed.
Any suggestions on topologies, transistors, white papers, etc? I'm
considering the NXP BFU590Q silicon bipolar transistor, which I have used in
a transformer feedback configuration at 100MHz with less than -180dBc/Hz PN.
But this topology doesn't appear practical for 400MHz due to the difficulty
maintaining a high collector impedance at that frequency with a transformer.
Nor do I need to control the gain, which is one of the features of the
transformer-feedback topology. I was thinking about common emitter with
inductive emitter degeneration. Not sure cascode is right for this UHF
application.
Lifespeed
Hi Time Nuts,
I have a need for a low phase noise, noise floor and noise figure amplifier
at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the best of
which degrades phase noise by a couple dB. I'm working with a signal with
-172dBc/Hz PN, so not much tolerance for degradation here. The input signal
level is only 3dBm, so noise figure still matters as well. I'm looking for
15dB gain, 16dBm P1. The residual phase noise would have to be better than
-180dBc/Hz, and I would probably operate the amplifier slightly compressed.
Any suggestions on topologies, transistors, white papers, etc? I'm
considering the NXP BFU590Q silicon bipolar transistor, which I have used in
a transformer feedback configuration at 100MHz with less than -180dBc/Hz PN.
But this topology doesn't appear practical for 400MHz due to the difficulty
maintaining a high collector impedance at that frequency with a transformer.
Nor do I need to control the gain, which is one of the features of the
transformer-feedback topology. I was thinking about common emitter with
inductive emitter degeneration. Not sure cascode is right for this UHF
application.
Lifespeed
J
jimlux
Fri, Jan 10, 2020 2:01 AM
On 1/9/20 5:38 PM, Lifespeed wrote:
Hi Time Nuts,
I have a need for a low phase noise, noise floor and noise figure amplifier
at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the best of
which degrades phase noise by a couple dB. I'm working with a signal with
-172dBc/Hz PN, so not much tolerance for degradation here. The input signal
level is only 3dBm, so noise figure still matters as well. I'm looking for
15dB gain, 16dBm P1. The residual phase noise would have to be better than
-180dBc/Hz, and I would probably operate the amplifier slightly compressed.
So you've tried something like the minicircuits CMA-5043? 18dB gain,
0.75 dB NF, P1dB 18dBm
They've got a whole raft of 0.5dB NF with 20+ dB gain, P1dB in the 17-19
dBm range - SAV-331, SAV-541, etc.
From the graphs, the NF is down around 0.3 dB below 500 MHz, if you
keep it reasonably cool (25C.. +85 the NF goes up)
If you need lower than that, I can ask around about discrete designs.
There's some group in Norway that is using FETs from Switzerland and
getting L band noise temps in the single digit Kelvin range. (without
cryocooling). I don't know if it would go down to UHF and hold that
performance
Any suggestions on topologies, transistors, white papers, etc? I'm
considering the NXP BFU590Q silicon bipolar transistor, which I have used in
a transformer feedback configuration at 100MHz with less than -180dBc/Hz PN.
But this topology doesn't appear practical for 400MHz due to the difficulty
maintaining a high collector impedance at that frequency with a transformer.
Nor do I need to control the gain, which is one of the features of the
transformer-feedback topology. I was thinking about common emitter with
inductive emitter degeneration. Not sure cascode is right for this UHF
application.
Lifespeed
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and follow the instructions there.
On 1/9/20 5:38 PM, Lifespeed wrote:
> Hi Time Nuts,
>
>
>
> I have a need for a low phase noise, noise floor and noise figure amplifier
> at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the best of
> which degrades phase noise by a couple dB. I'm working with a signal with
> -172dBc/Hz PN, so not much tolerance for degradation here. The input signal
> level is only 3dBm, so noise figure still matters as well. I'm looking for
> 15dB gain, 16dBm P1. The residual phase noise would have to be better than
> -180dBc/Hz, and I would probably operate the amplifier slightly compressed.
So you've tried something like the minicircuits CMA-5043? 18dB gain,
0.75 dB NF, P1dB 18dBm
They've got a whole raft of 0.5dB NF with 20+ dB gain, P1dB in the 17-19
dBm range - SAV-331, SAV-541, etc.
From the graphs, the NF is down around 0.3 dB below 500 MHz, if you
keep it reasonably cool (25C.. +85 the NF goes up)
If you need lower than that, I can ask around about discrete designs.
There's some group in Norway that is using FETs from Switzerland and
getting L band noise temps in the single digit Kelvin range. (without
cryocooling). I don't know if it would go down to UHF and hold that
performance
>
>
>
> Any suggestions on topologies, transistors, white papers, etc? I'm
> considering the NXP BFU590Q silicon bipolar transistor, which I have used in
> a transformer feedback configuration at 100MHz with less than -180dBc/Hz PN.
> But this topology doesn't appear practical for 400MHz due to the difficulty
> maintaining a high collector impedance at that frequency with a transformer.
> Nor do I need to control the gain, which is one of the features of the
> transformer-feedback topology. I was thinking about common emitter with
> inductive emitter degeneration. Not sure cascode is right for this UHF
> application.
>
>
>
> Lifespeed
>
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts@lists.febo.com
> To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>
BG
Bruce Griffiths
Fri, Jan 10, 2020 2:25 AM
That's not possible at room temperature since thermal noise will limit the residual PN to -180DbC/Hz with a noiseless amplifier and a +3dBm input.
Bruce
On 10 January 2020 at 14:38 Lifespeed lifespeed@claybuccellato.com wrote:
Hi Time Nuts,
I have a need for a low phase noise, noise floor and noise figure amplifier
at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the best of
which degrades phase noise by a couple dB. I'm working with a signal with
-172dBc/Hz PN, so not much tolerance for degradation here. The input signal
level is only 3dBm, so noise figure still matters as well. I'm looking for
15dB gain, 16dBm P1. The residual phase noise would have to be better than
-180dBc/Hz, and I would probably operate the amplifier slightly compressed.
Any suggestions on topologies, transistors, white papers, etc? I'm
considering the NXP BFU590Q silicon bipolar transistor, which I have used in
a transformer feedback configuration at 100MHz with less than -180dBc/Hz PN.
But this topology doesn't appear practical for 400MHz due to the difficulty
maintaining a high collector impedance at that frequency with a transformer.
Nor do I need to control the gain, which is one of the features of the
transformer-feedback topology. I was thinking about common emitter with
inductive emitter degeneration. Not sure cascode is right for this UHF
application.
Lifespeed
time-nuts mailing list -- time-nuts@lists.febo.com
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and follow the instructions there.
That's not possible at room temperature since thermal noise will limit the residual PN to -180DbC/Hz with a noiseless amplifier and a +3dBm input.
Bruce
> On 10 January 2020 at 14:38 Lifespeed <lifespeed@claybuccellato.com> wrote:
>
>
> Hi Time Nuts,
>
>
>
> I have a need for a low phase noise, noise floor and noise figure amplifier
> at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the best of
> which degrades phase noise by a couple dB. I'm working with a signal with
> -172dBc/Hz PN, so not much tolerance for degradation here. The input signal
> level is only 3dBm, so noise figure still matters as well. I'm looking for
> 15dB gain, 16dBm P1. The residual phase noise would have to be better than
> -180dBc/Hz, and I would probably operate the amplifier slightly compressed.
>
>
>
> Any suggestions on topologies, transistors, white papers, etc? I'm
> considering the NXP BFU590Q silicon bipolar transistor, which I have used in
> a transformer feedback configuration at 100MHz with less than -180dBc/Hz PN.
> But this topology doesn't appear practical for 400MHz due to the difficulty
> maintaining a high collector impedance at that frequency with a transformer.
> Nor do I need to control the gain, which is one of the features of the
> transformer-feedback topology. I was thinking about common emitter with
> inductive emitter degeneration. Not sure cascode is right for this UHF
> application.
>
>
>
> Lifespeed
>
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts@lists.febo.com
> To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
L
Lifespeed
Fri, Jan 10, 2020 2:25 AM
-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@lists.febo.com] On Behalf Of
jimlux
Sent: Thursday, January 9, 2020 6:02 PM
To: time-nuts@lists.febo.com
Subject: Re: [time-nuts] low phase noise, noise floor and noise figure
amplifier at 400MHz
So you've tried something like the minicircuits CMA-5043? 18dB gain,
0.75 dB NF, P1dB 18dBm
They've got a whole raft of 0.5dB NF with 20+ dB gain, P1dB in the 17-19 dBm
range - SAV-331, SAV-541, etc.
From the graphs, the NF is down around 0.3 dB below 500 MHz, if you keep it
reasonably cool (25C.. +85 the NF goes up)
If you need lower than that, I can ask around about discrete designs.
There's some group in Norway that is using FETs from Switzerland and
getting L band noise temps in the single digit Kelvin range. (without
cryocooling). I don't know if it would go down to UHF and hold that
performance
While there are lots of low NF options, this does not necessarily correlate
with low PN. Residual phase noise typically is not characterized and is
left as an exercise for the user. My experience has been PHEMTs (CMA-5043)
are not one of the better GaAs parts for low phase noise. The part with 2dB
PN degradation is a Mini-Circuits GALI-6+ InGaP HBT, and it is better than
any off-the-shelf 50 ohm amplifier I have tried so far.
I think it is likely I will need a Si or SiGe bipolar discrete design. I
have been reading an old paper " Guidelines for Designing BJT Amplifiers
with Low 1/f AM and PM Noise" linked on the NIST site and elsewhere.
https://tf.nist.gov/general/pdf/1139.pdf
Thanks,
Lifespeed
-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@lists.febo.com] On Behalf Of
jimlux
Sent: Thursday, January 9, 2020 6:02 PM
To: time-nuts@lists.febo.com
Subject: Re: [time-nuts] low phase noise, noise floor and noise figure
amplifier at 400MHz
So you've tried something like the minicircuits CMA-5043? 18dB gain,
0.75 dB NF, P1dB 18dBm
They've got a whole raft of 0.5dB NF with 20+ dB gain, P1dB in the 17-19 dBm
range - SAV-331, SAV-541, etc.
From the graphs, the NF is down around 0.3 dB below 500 MHz, if you keep it
reasonably cool (25C.. +85 the NF goes up)
If you need lower than that, I can ask around about discrete designs.
There's some group in Norway that is using FETs from Switzerland and
getting L band noise temps in the single digit Kelvin range. (without
cryocooling). I don't know if it would go down to UHF and hold that
performance
***********
While there are lots of low NF options, this does not necessarily correlate
with low PN. Residual phase noise typically is not characterized and is
left as an exercise for the user. My experience has been PHEMTs (CMA-5043)
are not one of the better GaAs parts for low phase noise. The part with 2dB
PN degradation is a Mini-Circuits GALI-6+ InGaP HBT, and it is better than
any off-the-shelf 50 ohm amplifier I have tried so far.
I think it is likely I will need a Si or SiGe bipolar discrete design. I
have been reading an old paper " Guidelines for Designing BJT Amplifiers
with Low 1/f AM and PM Noise" linked on the NIST site and elsewhere.
https://tf.nist.gov/general/pdf/1139.pdf
Thanks,
Lifespeed
GH
Gerhard Hoffmann
Fri, Jan 10, 2020 3:23 AM
Am 10.01.20 um 03:01 schrieb jimlux:
On 1/9/20 5:38 PM, Lifespeed wrote:
Hi Time Nuts,
I have a need for a low phase noise, noise floor and noise figure
amplifier
at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the
best of
which degrades phase noise by a couple dB. I'm working with a signal
with
-172dBc/Hz PN, so not much tolerance for degradation here. The input
signal
level is only 3dBm, so noise figure still matters as well. I'm
looking for
15dB gain, 16dBm P1. The residual phase noise would have to be
better than
-180dBc/Hz, and I would probably operate the amplifier slightly
compressed.
A friend of mine measured my SKY 75150 demo board at F= 0.35 dB last weekend
on 432 MHz for EME purposes. More careful measurements to follow.
chip = < https://www.digikey.de/products/de?keywords=863-1559-1-nd >
board = < https://www.digikey.de/products/de?keywords=863-1562 >
When I ever get it back :-) , I might characterize it for added phase
noise at 400 MHz,
but he should have his fair share of time to play with it.
Given the extra tiny SMD input inductor, an even better F must be possible.
The Mini Circuits SAV-551+ has a Fmin of ~ 0.08 dB at 450 MHz according
to the
data sheet IIRC. When I add 0.1 dB of losses, that is still outstanding.
Does anybody know of an ADS design kit for these parts? Spice is
probably hopeless.
ADS and MCL do not seem to go together well.
If you want to allow compression, there will be 1/f up conversion. 1/f
is completely
unspecified for these parts.
If you need lower than that, I can ask around about discrete designs.
There's some group in Norway that is using FETs from Switzerland and
getting L band noise temps in the single digit Kelvin range. (without
cryocooling). I don't know if it would go down to UHF and hold that
performance
Interesting. What are these FETs from Switzerland? Any pointers?
Any suggestions on topologies, transistors, white papers, etc? I'm
considering the NXP BFU590Q silicon bipolar transistor, which I have
used in
a transformer feedback configuration at 100MHz with less than
-180dBc/Hz PN.
But this topology doesn't appear practical for 400MHz due to the
difficulty
maintaining a high collector impedance at that frequency with a
transformer.
Have you tried Infineon BFQ19S ? I just have bought quite a lot of them.
Nor do I need to control the gain, which is one of the features of the
transformer-feedback topology. I was thinking about common emitter with
inductive emitter degeneration. Not sure cascode is right for this UHF
application.
Cascodes do not add noise in real life. p-HEMTs have ridiculously low output
impedance, so cascoding with SiGe BJT might be a good thing. The output
could be a low-Q tuned tank if the impedance needs to be high.
regards, Gerhard
Am 10.01.20 um 03:01 schrieb jimlux:
> On 1/9/20 5:38 PM, Lifespeed wrote:
>> Hi Time Nuts,
>>
>>
>> I have a need for a low phase noise, noise floor and noise figure
>> amplifier
>> at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the
>> best of
>> which degrades phase noise by a couple dB. I'm working with a signal
>> with
>> -172dBc/Hz PN, so not much tolerance for degradation here. The input
>> signal
>> level is only 3dBm, so noise figure still matters as well. I'm
>> looking for
>> 15dB gain, 16dBm P1. The residual phase noise would have to be
>> better than
>> -180dBc/Hz, and I would probably operate the amplifier slightly
>> compressed.
A friend of mine measured my SKY 75150 demo board at F= 0.35 dB last weekend
on 432 MHz for EME purposes. More careful measurements to follow.
chip = < https://www.digikey.de/products/de?keywords=863-1559-1-nd >
board = < https://www.digikey.de/products/de?keywords=863-1562 >
When I ever get it back :-) , I might characterize it for added phase
noise at 400 MHz,
but he should have his fair share of time to play with it.
Given the extra tiny SMD input inductor, an even better F must be possible.
The Mini Circuits SAV-551+ has a Fmin of ~ 0.08 dB at 450 MHz according
to the
data sheet IIRC. When I add 0.1 dB of losses, that is still outstanding.
Does anybody know of an ADS design kit for these parts? Spice is
probably hopeless.
ADS and MCL do not seem to go together well.
If you want to allow compression, there will be 1/f up conversion. 1/f
is completely
unspecified for these parts.
> If you need lower than that, I can ask around about discrete designs.
> There's some group in Norway that is using FETs from Switzerland and
> getting L band noise temps in the single digit Kelvin range. (without
> cryocooling). I don't know if it would go down to UHF and hold that
> performance
>
Interesting. What are these FETs from Switzerland? Any pointers?
>>
>>
>> Any suggestions on topologies, transistors, white papers, etc? I'm
>> considering the NXP BFU590Q silicon bipolar transistor, which I have
>> used in
>> a transformer feedback configuration at 100MHz with less than
>> -180dBc/Hz PN.
>> But this topology doesn't appear practical for 400MHz due to the
>> difficulty
>> maintaining a high collector impedance at that frequency with a
>> transformer.
Have you tried Infineon BFQ19S ? I just have bought quite a lot of them.
>> Nor do I need to control the gain, which is one of the features of the
>> transformer-feedback topology. I was thinking about common emitter with
>> inductive emitter degeneration. Not sure cascode is right for this UHF
>> application.
>>
Cascodes do not add noise in real life. p-HEMTs have ridiculously low output
impedance, so cascoding with SiGe BJT might be a good thing. The output
could be a low-Q tuned tank if the impedance needs to be high.
regards, Gerhard
JM
John Miles
Fri, Jan 10, 2020 6:23 AM
Any suggestions on topologies, transistors, white papers, etc? I'm
considering the NXP BFU590Q silicon bipolar transistor, which I have used
a transformer feedback configuration at 100MHz with less than -180dBc/Hz
PN.
You could take a look at the approach behind the option-K22 amplifiers that
were sold by HP for use with the 3048A. I've got one of those but I needed
a couple more of them at one point, so I built some (literally) quick and
dirty copies with BFG591 transistors with good results.
I've mentioned them before on here, I think. There are a few photos and
plots at http://www.ke5fx.com/k22.htm . Basically a CE amplifier with an
LED-referenced bias stage originally suggested by Bruce Griffiths.
A single stage won't deliver the gain you're after, but these amplifiers are
relatively well-behaved and can be cascaded at will. That was the original
intent with the K22, which consisted of two independent amps in one box. If
you want to use the K22 amps to keep oscillators from injection locking, you
pretty much have to cascade them due to lack of reverse isolation. The
homebrew hack job is similar to the HP original in most respects including
that one.
I'd be inclined to use a dual-emitter part (BUF590G) instead of the BUF590Q,
if I were building more of these.
-- john, KE5FX
> Any suggestions on topologies, transistors, white papers, etc? I'm
> considering the NXP BFU590Q silicon bipolar transistor, which I have used
in
> a transformer feedback configuration at 100MHz with less than -180dBc/Hz
> PN.
You could take a look at the approach behind the option-K22 amplifiers that
were sold by HP for use with the 3048A. I've got one of those but I needed
a couple more of them at one point, so I built some (literally) quick and
dirty copies with BFG591 transistors with good results.
I've mentioned them before on here, I think. There are a few photos and
plots at http://www.ke5fx.com/k22.htm . Basically a CE amplifier with an
LED-referenced bias stage originally suggested by Bruce Griffiths.
A single stage won't deliver the gain you're after, but these amplifiers are
relatively well-behaved and can be cascaded at will. That was the original
intent with the K22, which consisted of two independent amps in one box. If
you want to use the K22 amps to keep oscillators from injection locking, you
pretty much have to cascade them due to lack of reverse isolation. The
homebrew hack job is similar to the HP original in most respects including
that one.
I'd be inclined to use a dual-emitter part (BUF590G) instead of the BUF590Q,
if I were building more of these.
-- john, KE5FX
L
Lifespeed
Fri, Jan 10, 2020 5:40 PM
-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@lists.febo.com] On Behalf Of John
Miles
Sent: Thursday, January 9, 2020 10:23 PM
To: 'Discussion of precise time and frequency measurement'
time-nuts@lists.febo.com
Subject: Re: [time-nuts] low phase noise, noise floor and noise figure
amplifier at 400MHz
You could take a look at the approach behind the option-K22 amplifiers that
were sold by HP for use with the 3048A. I've got one of those but I needed
a couple more of them at one point, so I built some (literally) quick and
dirty copies with BFG591 transistors with good results.
I've mentioned them before on here, I think. There are a few photos and
plots at http://www.ke5fx.com/k22.htm . Basically a CE amplifier with an
LED-referenced bias stage originally suggested by Bruce Griffiths.
A single stage won't deliver the gain you're after, but these amplifiers are
relatively well-behaved and can be cascaded at will. That was the original
intent with the K22, which consisted of two independent amps in one box. If
you want to use the K22 amps to keep oscillators from injection locking, you
pretty much have to cascade them due to lack of reverse isolation. The
homebrew hack job is similar to the HP original in most respects including
that one.
I'd be inclined to use a dual-emitter part (BUF590G) instead of the BUF590Q,
if I were building more of these.
-- john, KE5FX
Thanks for the info. While I have fond memories of using the HP3048 phase
noise measurement system early in my career, a review of the data indicate
the K22 does not meet my requirements.
-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@lists.febo.com] On Behalf Of John
Miles
Sent: Thursday, January 9, 2020 10:23 PM
To: 'Discussion of precise time and frequency measurement'
<time-nuts@lists.febo.com>
Subject: Re: [time-nuts] low phase noise, noise floor and noise figure
amplifier at 400MHz
You could take a look at the approach behind the option-K22 amplifiers that
were sold by HP for use with the 3048A. I've got one of those but I needed
a couple more of them at one point, so I built some (literally) quick and
dirty copies with BFG591 transistors with good results.
I've mentioned them before on here, I think. There are a few photos and
plots at http://www.ke5fx.com/k22.htm . Basically a CE amplifier with an
LED-referenced bias stage originally suggested by Bruce Griffiths.
A single stage won't deliver the gain you're after, but these amplifiers are
relatively well-behaved and can be cascaded at will. That was the original
intent with the K22, which consisted of two independent amps in one box. If
you want to use the K22 amps to keep oscillators from injection locking, you
pretty much have to cascade them due to lack of reverse isolation. The
homebrew hack job is similar to the HP original in most respects including
that one.
I'd be inclined to use a dual-emitter part (BUF590G) instead of the BUF590Q,
if I were building more of these.
-- john, KE5FX
************
Thanks for the info. While I have fond memories of using the HP3048 phase
noise measurement system early in my career, a review of the data indicate
the K22 does not meet my requirements.
MD
Magnus Danielson
Sat, Jan 18, 2020 2:57 PM
I think one should recall that for very deep phase-noise numbers for
far-out noise, we cannot remove the suspicion of cross-correlation
cancellation problems have overstated the phase-noise levels. I've seen
both instrument makers and oscillator makes handwaving to protect the
values which so far is understood to be non-physical.
Cheers,
Magnus
On 2020-01-10 03:25, Bruce Griffiths wrote:
That's not possible at room temperature since thermal noise will limit the residual PN to -180DbC/Hz with a noiseless amplifier and a +3dBm input.
Bruce
On 10 January 2020 at 14:38 Lifespeed lifespeed@claybuccellato.com wrote:
Hi Time Nuts,
I have a need for a low phase noise, noise floor and noise figure amplifier
at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the best of
which degrades phase noise by a couple dB. I'm working with a signal with
-172dBc/Hz PN, so not much tolerance for degradation here. The input signal
level is only 3dBm, so noise figure still matters as well. I'm looking for
15dB gain, 16dBm P1. The residual phase noise would have to be better than
-180dBc/Hz, and I would probably operate the amplifier slightly compressed.
Any suggestions on topologies, transistors, white papers, etc? I'm
considering the NXP BFU590Q silicon bipolar transistor, which I have used in
a transformer feedback configuration at 100MHz with less than -180dBc/Hz PN.
But this topology doesn't appear practical for 400MHz due to the difficulty
maintaining a high collector impedance at that frequency with a transformer.
Nor do I need to control the gain, which is one of the features of the
transformer-feedback topology. I was thinking about common emitter with
inductive emitter degeneration. Not sure cascode is right for this UHF
application.
Lifespeed
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
and follow the instructions there.
I think one should recall that for very deep phase-noise numbers for
far-out noise, we cannot remove the suspicion of cross-correlation
cancellation problems have overstated the phase-noise levels. I've seen
both instrument makers and oscillator makes handwaving to protect the
values which so far is understood to be non-physical.
Cheers,
Magnus
On 2020-01-10 03:25, Bruce Griffiths wrote:
> That's not possible at room temperature since thermal noise will limit the residual PN to -180DbC/Hz with a noiseless amplifier and a +3dBm input.
>
> Bruce
>
>> On 10 January 2020 at 14:38 Lifespeed <lifespeed@claybuccellato.com> wrote:
>>
>>
>> Hi Time Nuts,
>>
>>
>>
>> I have a need for a low phase noise, noise floor and noise figure amplifier
>> at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the best of
>> which degrades phase noise by a couple dB. I'm working with a signal with
>> -172dBc/Hz PN, so not much tolerance for degradation here. The input signal
>> level is only 3dBm, so noise figure still matters as well. I'm looking for
>> 15dB gain, 16dBm P1. The residual phase noise would have to be better than
>> -180dBc/Hz, and I would probably operate the amplifier slightly compressed.
>>
>>
>>
>> Any suggestions on topologies, transistors, white papers, etc? I'm
>> considering the NXP BFU590Q silicon bipolar transistor, which I have used in
>> a transformer feedback configuration at 100MHz with less than -180dBc/Hz PN.
>> But this topology doesn't appear practical for 400MHz due to the difficulty
>> maintaining a high collector impedance at that frequency with a transformer.
>> Nor do I need to control the gain, which is one of the features of the
>> transformer-feedback topology. I was thinking about common emitter with
>> inductive emitter degeneration. Not sure cascode is right for this UHF
>> application.
>>
>>
>>
>> Lifespeed
>>
>>
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts@lists.febo.com
>> To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
>> and follow the instructions there.
> _______________________________________________
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> and follow the instructions there.
PM
Patrick Murphy
Sat, Jan 18, 2020 4:29 PM
Magnus,
Well you kindly explain what you mean by your comment "I've seen
both instrument makers and oscillator makes handwaving to protect the values
which so far is understood to be non-physical." , especially the
non-physical part.
While I can keep up with a lot of the discussions here, I will likely die
an old man before I consider myself anything more than a noob. Thanks for
your patience.
-Pat (KG5YPQ)
On Sat, Jan 18, 2020, 8:57 AM Magnus Danielson magnus@rubidium.se wrote:
I think one should recall that for very deep phase-noise numbers for
far-out noise, we cannot remove the suspicion of cross-correlation
cancellation problems have overstated the phase-noise levels. I've seen
both instrument makers and oscillator makes handwaving to protect the
values which so far is understood to be non-physical.
Cheers,
Magnus
On 2020-01-10 03:25, Bruce Griffiths wrote:
That's not possible at room temperature since thermal noise will limit
the residual PN to -180DbC/Hz with a noiseless amplifier and a +3dBm input.
Hi Time Nuts,
I have a need for a low phase noise, noise floor and noise figure
at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the best
which degrades phase noise by a couple dB. I'm working with a signal
-172dBc/Hz PN, so not much tolerance for degradation here. The input
level is only 3dBm, so noise figure still matters as well. I'm looking
15dB gain, 16dBm P1. The residual phase noise would have to be better
-180dBc/Hz, and I would probably operate the amplifier slightly
Any suggestions on topologies, transistors, white papers, etc? I'm
considering the NXP BFU590Q silicon bipolar transistor, which I have
a transformer feedback configuration at 100MHz with less than
But this topology doesn't appear practical for 400MHz due to the
maintaining a high collector impedance at that frequency with a
Nor do I need to control the gain, which is one of the features of the
transformer-feedback topology. I was thinking about common emitter with
inductive emitter degeneration. Not sure cascode is right for this UHF
application.
Lifespeed
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
and follow the instructions there.
and follow the instructions there.
Magnus,
Well you kindly explain what you mean by your comment "I've seen
both instrument makers and oscillator makes handwaving to protect the values
which so far is understood to be non-physical." , especially the
non-physical part.
While I can keep up with a lot of the discussions here, I will likely die
an old man before I consider myself anything more than a noob. Thanks for
your patience.
-Pat (KG5YPQ)
On Sat, Jan 18, 2020, 8:57 AM Magnus Danielson <magnus@rubidium.se> wrote:
> I think one should recall that for very deep phase-noise numbers for
> far-out noise, we cannot remove the suspicion of cross-correlation
> cancellation problems have overstated the phase-noise levels. I've seen
> both instrument makers and oscillator makes handwaving to protect the
> values which so far is understood to be non-physical.
>
> Cheers,
> Magnus
>
> On 2020-01-10 03:25, Bruce Griffiths wrote:
> > That's not possible at room temperature since thermal noise will limit
> the residual PN to -180DbC/Hz with a noiseless amplifier and a +3dBm input.
> >
> > Bruce
> >
> >> On 10 January 2020 at 14:38 Lifespeed <lifespeed@claybuccellato.com>
> wrote:
> >>
> >>
> >> Hi Time Nuts,
> >>
> >>
> >>
> >> I have a need for a low phase noise, noise floor and noise figure
> amplifier
> >> at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the best
> of
> >> which degrades phase noise by a couple dB. I'm working with a signal
> with
> >> -172dBc/Hz PN, so not much tolerance for degradation here. The input
> signal
> >> level is only 3dBm, so noise figure still matters as well. I'm looking
> for
> >> 15dB gain, 16dBm P1. The residual phase noise would have to be better
> than
> >> -180dBc/Hz, and I would probably operate the amplifier slightly
> compressed.
> >>
> >>
> >>
> >> Any suggestions on topologies, transistors, white papers, etc? I'm
> >> considering the NXP BFU590Q silicon bipolar transistor, which I have
> used in
> >> a transformer feedback configuration at 100MHz with less than
> -180dBc/Hz PN.
> >> But this topology doesn't appear practical for 400MHz due to the
> difficulty
> >> maintaining a high collector impedance at that frequency with a
> transformer.
> >> Nor do I need to control the gain, which is one of the features of the
> >> transformer-feedback topology. I was thinking about common emitter with
> >> inductive emitter degeneration. Not sure cascode is right for this UHF
> >> application.
> >>
> >>
> >>
> >> Lifespeed
> >>
> >>
> >>
> >> _______________________________________________
> >> time-nuts mailing list -- time-nuts@lists.febo.com
> >> To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> >> and follow the instructions there.
> > _______________________________________________
> > time-nuts mailing list -- time-nuts@lists.febo.com
> > To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> > and follow the instructions there.
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts@lists.febo.com
> To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>
MD
Magnus Danielson
Sat, Jan 18, 2020 5:46 PM
Patrick,
I try to share what I have learned as generously as others before me
have done. Somewhere along the line I transitioned from noob to actually
know something and now, well, I can't claim complete lack of knowledge
anymore. But, I enjoy the many questions, as it forces me to think,
think and think. There is always things to learn in obscure corners and
plain questions. It turns out that if you are stringent enough there is
many white spots that you may not expect. So there is still things to
learn and angles to cover. So thank you for asking questions, it is the
constant challenge that makes us think, share and learn stuff.
Most importantly, we need to enjoy the fun of challenge and learning!
Cheers,
Magnus
On 2020-01-18 17:29, Patrick Murphy wrote:
Magnus,
Well you kindly explain what you mean by your comment "I've seen
both instrument makers and oscillator makes handwaving to protect the values
which so far is understood to be non-physical." , especially the
non-physical part.
While I can keep up with a lot of the discussions here, I will likely die
an old man before I consider myself anything more than a noob. Thanks for
your patience.
-Pat (KG5YPQ)
On Sat, Jan 18, 2020, 8:57 AM Magnus Danielson magnus@rubidium.se wrote:
I think one should recall that for very deep phase-noise numbers for
far-out noise, we cannot remove the suspicion of cross-correlation
cancellation problems have overstated the phase-noise levels. I've seen
both instrument makers and oscillator makes handwaving to protect the
values which so far is understood to be non-physical.
Cheers,
Magnus
On 2020-01-10 03:25, Bruce Griffiths wrote:
That's not possible at room temperature since thermal noise will limit
the residual PN to -180DbC/Hz with a noiseless amplifier and a +3dBm input.
Hi Time Nuts,
I have a need for a low phase noise, noise floor and noise figure
at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the best
which degrades phase noise by a couple dB. I'm working with a signal
-172dBc/Hz PN, so not much tolerance for degradation here. The input
level is only 3dBm, so noise figure still matters as well. I'm looking
15dB gain, 16dBm P1. The residual phase noise would have to be better
-180dBc/Hz, and I would probably operate the amplifier slightly
Any suggestions on topologies, transistors, white papers, etc? I'm
considering the NXP BFU590Q silicon bipolar transistor, which I have
a transformer feedback configuration at 100MHz with less than
But this topology doesn't appear practical for 400MHz due to the
maintaining a high collector impedance at that frequency with a
Nor do I need to control the gain, which is one of the features of the
transformer-feedback topology. I was thinking about common emitter with
inductive emitter degeneration. Not sure cascode is right for this UHF
application.
Lifespeed
time-nuts mailing list -- time-nuts@lists.febo.com
To unsubscribe, go to
and follow the instructions there.
and follow the instructions there.
Patrick,
I try to share what I have learned as generously as others before me
have done. Somewhere along the line I transitioned from noob to actually
know something and now, well, I can't claim complete lack of knowledge
anymore. But, I enjoy the many questions, as it forces me to think,
think and think. There is always things to learn in obscure corners and
plain questions. It turns out that if you are stringent enough there is
many white spots that you may not expect. So there is still things to
learn and angles to cover. So thank you for asking questions, it is the
constant challenge that makes us think, share and learn stuff.
Most importantly, we need to enjoy the fun of challenge and learning!
Cheers,
Magnus
On 2020-01-18 17:29, Patrick Murphy wrote:
> Magnus,
>
> Well you kindly explain what you mean by your comment "I've seen
> both instrument makers and oscillator makes handwaving to protect the values
> which so far is understood to be non-physical." , especially the
> non-physical part.
>
> While I can keep up with a lot of the discussions here, I will likely die
> an old man before I consider myself anything more than a noob. Thanks for
> your patience.
>
> -Pat (KG5YPQ)
>
>
> On Sat, Jan 18, 2020, 8:57 AM Magnus Danielson <magnus@rubidium.se> wrote:
>
>> I think one should recall that for very deep phase-noise numbers for
>> far-out noise, we cannot remove the suspicion of cross-correlation
>> cancellation problems have overstated the phase-noise levels. I've seen
>> both instrument makers and oscillator makes handwaving to protect the
>> values which so far is understood to be non-physical.
>>
>> Cheers,
>> Magnus
>>
>> On 2020-01-10 03:25, Bruce Griffiths wrote:
>>> That's not possible at room temperature since thermal noise will limit
>> the residual PN to -180DbC/Hz with a noiseless amplifier and a +3dBm input.
>>> Bruce
>>>
>>>> On 10 January 2020 at 14:38 Lifespeed <lifespeed@claybuccellato.com>
>> wrote:
>>>>
>>>> Hi Time Nuts,
>>>>
>>>>
>>>>
>>>> I have a need for a low phase noise, noise floor and noise figure
>> amplifier
>>>> at 400MHz. I have tried some off-the-shelf 50 ohm amplifiers, the best
>> of
>>>> which degrades phase noise by a couple dB. I'm working with a signal
>> with
>>>> -172dBc/Hz PN, so not much tolerance for degradation here. The input
>> signal
>>>> level is only 3dBm, so noise figure still matters as well. I'm looking
>> for
>>>> 15dB gain, 16dBm P1. The residual phase noise would have to be better
>> than
>>>> -180dBc/Hz, and I would probably operate the amplifier slightly
>> compressed.
>>>>
>>>>
>>>> Any suggestions on topologies, transistors, white papers, etc? I'm
>>>> considering the NXP BFU590Q silicon bipolar transistor, which I have
>> used in
>>>> a transformer feedback configuration at 100MHz with less than
>> -180dBc/Hz PN.
>>>> But this topology doesn't appear practical for 400MHz due to the
>> difficulty
>>>> maintaining a high collector impedance at that frequency with a
>> transformer.
>>>> Nor do I need to control the gain, which is one of the features of the
>>>> transformer-feedback topology. I was thinking about common emitter with
>>>> inductive emitter degeneration. Not sure cascode is right for this UHF
>>>> application.
>>>>
>>>>
>>>>
>>>> Lifespeed
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> time-nuts mailing list -- time-nuts@lists.febo.com
>>>> To unsubscribe, go to
>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
>>>> and follow the instructions there.
>>> _______________________________________________
>>> time-nuts mailing list -- time-nuts@lists.febo.com
>>> To unsubscribe, go to
>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
>>> and follow the instructions there.
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts@lists.febo.com
>> To unsubscribe, go to
>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
>> and follow the instructions there.
>>
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> To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
