Prescalers ?
Hi:
I'm pondering ways I can use my collection of time interval counters (most of which also have frequency counter modes) to measure the frequency of signals at frequencies up to 1.3 GHz. None these units will deal with frequencies higher than 512 MHz.
Does anyone have any suggestions for off the shelf time nut quality Prescalers ? Or would I be better off just buying something along the lines of a suitably equipped 53131A or 53132A ? (If I end up buying another counter I would rather buy another universal counter I could use for time nuts stuff, vs simply buying a frequency counter for this application.)
Thanks in advance for any suggestions.
Mark Spencer
Hi
If you have a one time need to get to 1.3 GHz then some sort of cobbled together dead bug chip solution
would be my pick of how to get it done. Cost wise it wold be hard to beat. There are also cooled up approaches
with signal generators and mixers ( no don’t go there …).
If you will be doing this a lot and handling a variety of signals, get a real instrument prescaler (or a counter
with one built in). There are a lot of weird things a good design will address that makes it a more pleasant
thing to use. If I was shopping, I’d go a bit higher than 1.3 GHz. You never know what you might need next year :)
The good news TimeNut wise is that all of the approaches are just simple dividers. Sensitivity, modulation acceptance,
and immunity to going off into freerun modes matter. If they lock up, all the approaches I’m aware of are equally accurate.
Bob
On Jan 24, 2019, at 12:06 AM, Mark Spencer mark@alignedsolutions.com wrote:
Hi:
I'm pondering ways I can use my collection of time interval counters (most of which also have frequency counter modes) to measure the frequency of signals at frequencies up to 1.3 GHz. None these units will deal with frequencies higher than 512 MHz.
Does anyone have any suggestions for off the shelf time nut quality Prescalers ? Or would I be better off just buying something along the lines of a suitably equipped 53131A or 53132A ? (If I end up buying another counter I would rather buy another universal counter I could use for time nuts stuff, vs simply buying a frequency counter for this application.)
Thanks in advance for any suggestions.
Mark Spencer
time-nuts mailing list -- time-nuts@lists.febo.com
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and follow the instructions there.
Mark,
I had pretty good luck with a Hittite prescaler built into a board for the
5328 as outlined by Bert, VE2ZAZ.
http://ve2zaz.net/hp5328a/hp5328a_prescaler.htm
It's a wee bit deaf as frequency goes up, but works just fine!
Bob
On Thu, Jan 24, 2019 at 1:00 AM Mark Spencer mark@alignedsolutions.com
wrote:
Hi:
I'm pondering ways I can use my collection of time interval counters
(most of which also have frequency counter modes) to measure the frequency
of signals at frequencies up to 1.3 GHz. None these units will deal with
frequencies higher than 512 MHz.
Does anyone have any suggestions for off the shelf time nut quality
Prescalers ? Or would I be better off just buying something along the
lines of a suitably equipped 53131A or 53132A ? (If I end up buying
another counter I would rather buy another universal counter I could use
for time nuts stuff, vs simply buying a frequency counter for this
application.)
Thanks in advance for any suggestions.
Mark Spencer
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.
On 1/24/2019 5:17 AM, Bob kb8tq wrote:
Hi
If you have a one time need to get to 1.3 GHz then some sort of cobbled together dead bug chip solution
would be my pick of how to get it done. Cost wise it wold be hard to beat. There are also cooled up approaches
It may seem like prescalers are a simple fool proof technology,
but actually they are far from it. I got educated 40 years ago
when I designed the HP 5334B counter C channel. The 5334A used
an HP made divide by 10 prescaler that cost $100. I replaced
it with a $2 COTS divide by 16 prescaler. There was a production
test for the 34A that used an HP8660 synthesized sig gen. I
wanted to leverage this test for the 34B. The test IIRC involved
driving the C channel with 1.3 GHz at the minimum specified
sensitivity. But it called out using a mini-circuits 1 GHz
high pass filter between the 8660 and the 5334A. What? Turns
out that the wideband noise floor of the 8660 corrupted
the measurement on the 34A, unless this filter was used.
Also turned out that the 5334B
with a completely different C channel had the same problem.
OTOH, the 5316 did NOT have this problem. It used a different
HP made prescaler than the 34A. What was different is that
the 5316 prescaler had STATIC flip flops. Unfortunately, I
don't know of any COTS static flip flops that are available.
If the signal you are trying to measure is very clean, you
can get good results just about any prescaler. You will need
to arrange for the drive level to be in the "sweet spot" for
that prescaler. Otherwise, all bets are off. Getting a prescaler
that works over a wide dynamic range is whole 'nother discussion.
Rick N6RK
HiI use the Moto 12080 prescaler chip for that application on my various counters. it's strappable for Div by 10 and works in excess of 1 GHz, easy to feed. Sensitivity in the -20 Dbm range 50 ohms. SMT package. Cheap too. I have some excess boards 3/8 inch by 1 1/2 inch with on-board regulator. if anyone is interested. Bob, KE6F
-----Original Message-----
From: Richard (Rick) Karlquist richard@karlquist.com
To: Discussion of precise time and frequency measurement time-nuts@lists.febo.com; Bob kb8tq kb8tq@n1k.org
Sent: Thu, Jan 24, 2019 9:01 am
Subject: Re: [time-nuts] Prescalers ?
On 1/24/2019 5:17 AM, Bob kb8tq wrote:
Hi
If you have a one time need to get to 1.3 GHz then some sort of cobbled together dead bug chip solution
would be my pick of how to get it done. Cost wise it wold be hard to beat. There are also cooled up approaches
It may seem like prescalers are a simple fool proof technology,
but actually they are far from it. I got educated 40 years ago
when I designed the HP 5334B counter C channel. The 5334A used
an HP made divide by 10 prescaler that cost $100. I replaced
it with a $2 COTS divide by 16 prescaler. There was a production
test for the 34A that used an HP8660 synthesized sig gen. I
wanted to leverage this test for the 34B. The test IIRC involved
driving the C channel with 1.3 GHz at the minimum specified
sensitivity. But it called out using a mini-circuits 1 GHz
high pass filter between the 8660 and the 5334A. What? Turns
out that the wideband noise floor of the 8660 corrupted
the measurement on the 34A, unless this filter was used.
Also turned out that the 5334B
with a completely different C channel had the same problem.
OTOH, the 5316 did NOT have this problem. It used a different
HP made prescaler than the 34A. What was different is that
the 5316 prescaler had STATIC flip flops. Unfortunately, I
don't know of any COTS static flip flops that are available.
If the signal you are trying to measure is very clean, you
can get good results just about any prescaler. You will need
to arrange for the drive level to be in the "sweet spot" for
that prescaler. Otherwise, all bets are off. Getting a prescaler
that works over a wide dynamic range is whole 'nother discussion.
Rick N6RK
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.