I will have two Trimble Thunderbolts GPSDO, that I will be selling.
Both were bought thru the Time-Nuts purchases. There is nothing wrong
with these units, they are operational, and surplus to my needs.
One unit comes with the Ault power supply and power connector.
The second unit comes with
> Mike,
> That PS is a most curious problem. For reduced leakage fields from
> 60Hz transformers, it was common to have a wide copper strap
> wrapped around the transformer in the same orientation as the
> windings.
> This strap was the full width of the winding bobbin, but
> Hi Mike:
> I think it's National semi that has an app note talking about how
> the topology relates to noise output. Some are bad others are much
> better.
> Have Fun,
> Brooke Clarke
> http://www.prc68.com
Hi Brooke,
Do you recall the number or title of the National app note?
One of the t
Patrick wrote:
Thanks John
With regard to frequency and price, low frequency is fine for me and I
am hoping to buy something for < $250-Patrick
The HP 3336 (A,B,C) is similar to the 3325 but somewhat lesser
capabilities and can be a bit cheaper. There is one on eBay "in working
condition"
Anyone else playing with one of these Z3817A boxes that are/were
available on that marketplace which shall not be named?
The Z3817A appears to be essential a discipling box for an E1938. I'm
still not sure yet what the disciplining input is.
I'd love a manual, but I haven't found one yet.
Mike,
That PS is a most curious problem. For reduced leakage fields from
60Hz transformers, it was common to have a wide copper strap
wrapped around the transformer in the same orientation as the windings.
This strap was the full width of the winding bobbin, but formed a shorted
turn on the outsi
Hi Mike:
I think it's National semi that has an app note talking about how the topology
relates to noise output. Some are bad others are much better.
Have Fun,
Brooke Clarke
http://www.prc68.com
Mike Monett wrote:
> And be mindful that some frequency-standard devices contain
> i
In message: <4813.1245444...@critter.freebsd.dk>
"Poul-Henning Kamp" writes:
: In message <20090619.143448.2102305600@bsdimp.com>, "M. Warner Losh"
writes
: :
: >In message: <4a3bf553.20...@rubidium.dyndns.org>
: >Magnus Danielson writes:
: >: Have any of you seen the
> And be mindful that some frequency-standard devices contain
> integrated DC-DC switching converters - like my HP 58540A GPS-DO.
> The noise from the HP DC converters was spraying RFI every 100 kHz
> or so on the HF bands. After trying various RFI abatement
> measures, i
Poul-Henning Kamp skrev:
In message <20090619.143448.2102305600@bsdimp.com>, "M. Warner Losh" writes
:
In message: <4a3bf553.20...@rubidium.dyndns.org>
Magnus Danielson writes:
: Have any of you seen the reported problems?
"These counts started at 0 roughly at midnight UTC 6 Jan
M. Warner Losh skrev:
In message: <4a3bf553.20...@rubidium.dyndns.org>
Magnus Danielson writes:
: Have any of you seen the reported problems?
"These counts started at 0 roughly at midnight UTC 6 Jan 1980"
What does "roughly" mean here in this context?
Well, GPS and UTC was aligne
In message <20090619.143448.2102305600@bsdimp.com>, "M. Warner Losh" writes
:
>In message: <4a3bf553.20...@rubidium.dyndns.org>
>Magnus Danielson writes:
>: Have any of you seen the reported problems?
>
>"These counts started at 0 roughly at midnight UTC 6 Jan 1980"
>
>What does "r
In message: <4a3bf553.20...@rubidium.dyndns.org>
Magnus Danielson writes:
: Have any of you seen the reported problems?
"These counts started at 0 roughly at midnight UTC 6 Jan 1980"
What does "roughly" mean here in this context?
Warner
_
Fellow time-nuts,
Have any of you seen the reported problems?
Cheers,
Magnus
--- Begin Message ---
The USCG NAVCEN has received multiple reports of GPS problems
beginning on or about 11-14 June 2009. During this timeframe, two of
the counters providing a truncated representation of GPS week i
Rex,
Your 5370A is performing well. While it's possible to use the
adjustment procedure to gain a few ps better readings, the
result is largely an illusion & won't produce better results with
real world signals.
If you choose to wander into the adjustment procedures, be
sure to have the requ
Rex wrote:
John Miles wrote:
The procedure Bruce was describing is basically the jitter test from the
manual, at
http://cp.literature.agilent.com/litweb/pdf/05370-90031.pdf (this
is actually the same copy that David Kirkby scanned a few years ago,
hosted
by Agilent.) Follow the directions o
John Miles wrote:
The procedure Bruce was describing is basically the jitter test from the
manual, at http://cp.literature.agilent.com/litweb/pdf/05370-90031.pdf (this
is actually the same copy that David Kirkby scanned a few years ago, hosted
by Agilent.) Follow the directions on page 3-11 and
"The other issue is noise from a switcher."
And be mindful that some frequency-standard devices contain integrated DC-DC
switching converters -- like my HP 58540A GPS-DO. The noise from the HP DC
converters was spraying RFI every 100 kHz or so on the HF bands. After
trying various RFI abate
Correction...
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on
Behalf Of Francesco Ledda
Sent: Friday, June 19, 2009 9:38 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Z3805 initial behavior after power up revi
Hi Patrick:
There are a bunch of signal sources that could be used.
The rack sized HP signal generators that weigh 50+ pounds were designed to have
very low phase noise and although now many years old are still very good for that.
The HP 3325() is the only signal generator that has adjustable
Robert Darlington wrote:
As John Miles said, no HP signal generator should produce a distorted output
at low level. My Tektronix does!
It depends on how they lower the signal level. If the signal level is
lowered using a traditional attenuator, the distortion will be unchanged,
but if the si
Patrick,
Using a large fixed attenuator should work fine. I learned the attenuator
trick when dealing with some variable gain amp chips from Analog. Instead
of varying the gain, they run at some fixed level that produces a clean
output, and vary the attenuation level to prevent non-linear effect
Patrick,
If signal tracing in a "mystery" circuit is important, I
would look for a generator with external FM input.
This feature is common in upscale units. Using a basic
audio function generator on the FM input, you can
supply 2 tone FM, switching at 1 or 2Hz which is
easy to identify in the
Hello Pat,
Ebay could be your friend in locating a signal generator, as well as
researching availability and pricing.
My perspective is that Ebay is the big flea market in the ether
and you do not know what you got, till you get it on your test bench
and exercise it.
Bid accordingly, most d
Variation due to environment are deterministic and are nor part of aging.
Ageing needs to measured in conditions that remove ambient induced
perturbations. I used to put crystal oscillators in high quality
environmental chambers that kept temp, humidity and pressure constant and
measure the ageing.
I took a look at the phase noise of a 3325B and as Jim said, the phase
noise is not great -- about -60 dBc at 1 Hz offset. An external
reference cleans up the close in (<10 Hz) signal, but beyond about 10 Hz
the synthesizer noice drowns out the reference; from the noise from 10
Hz to about 3 k
Hi James
Thanks for your feedback on this.
My needs are probably very privative compared to those of the people on
this list. I service a lot of the time without a schematic so I spend a
lot of time figuring out how the circuit works. I was thinking that if I
injected a signal with a known wa
On 6/19/09 6:38 AM, "optoma...@rogers.com" wrote:
> Hey Robert
>
> Great tip about the attenuator.
>
> I looked up some models on the internet and some look fairly expensive.
> I know that I will always be injecting low voltage signals, do you think
> it would be wise to buy a cheaper fixed
We use a lot of 3325As in the lab at JPL (they used to have dozens of them at
the deep space network, so there are lots of them around). Some have the rear
panel option that puts out a sine wave up to 60MHz, which is fairly convenient.
The settability with lots o' digits is nice (that's why they
How accurate?
What frequency range?
What spectral performance (harmonics, spurs)?
One thing to watch out for on testing with very low level signals is leakage
out of the signal generator and into the unit under test via a path other than
the coax. When we test deep space transponders at work at
No distortion at low levels will occur with any signal generator worth
owning. Nothing from HP will do that.
-- john, KE5FX
> -Original Message-
> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on
> Behalf Of optoma...@rogers.com
> Sent: Friday, June 19, 2009 6:39 AM
Hey Robert
Great tip about the attenuator.
I looked up some models on the internet and some look fairly expensive.
I know that I will always be injecting low voltage signals, do you think
it would be wise to buy a cheaper fixed attenuator, let's say 20dB?, and
then just depend on the variable
Bruce Griffiths wrote:
Bruce
Rex wrote:
Bruce,
I've never seen you post a new thread as a response to an existing,
unrelated thread, as you've done here. You are not the first to do
this, but I thought you might be aware of these subtleties.
I was being lazy.
How can you tell, looking at th
I just bought an HP 3325A synthesizer/function generator that I really like
(for some things anyway) in about that price range. What you get is
probably dependent on what YOU need though. This thing is pretty limited
but this particular one has the high voltage option so the output goes up to
40
Oooh! Way to hijack a thread... on the first response too!
All Bulova Accutrons can be adjusted to work with a 1.5V cell.
If the specifications are to be believed, they are all supposed
to work up to 1.7V when properly adjusted... They don't, though.
The adjustment is not for the non watchmaker
Francesco Ledda wrote:
Aging cannot be predicted! If it could be predicetd, there would be no
aging.
Not entierly true. Even with a perfectly known aging, only a few
oscillators would bother to estimate and correct it. This can never be
perfectly done anyway, and there is only so many thing
Thanks John
With regard to frequency and price, low frequency is fine for me and I
am hoping to buy something for < $250-Patrick
John Miles wrote:
> Budget? Freq range?
>
> HP 8657As are good general-purpose SGs. Reliable, serviceable, and
> reasonably clean. Avoid 8656s and 8660s IMHO unless
Budget? Freq range?
HP 8657As are good general-purpose SGs. Reliable, serviceable, and
reasonably clean. Avoid 8656s and 8660s IMHO unless you can get one for
next to nothing.
If you don't mind getting your hands dirty there have been some inexpensive
8662As on the surplus market lately. They
Hey everyone
Sorry for the off topic post. I have received great advice in the past
with items for my little shop and I can't resist to ask again.
I am thinking about buying a signal generator. I suspect that I will
mostly use it to inject low uV/mV signals into the amplification stages
of the la
Rex wrote:
> Bruce Griffiths wrote:
>
>> What is the indicated std deviation of the delay between the STAR and
>> STOP inputs when connecting the rear panel 10MHz signal to both START
>> and STOP inputs using the STAR COM position of the channel mode switch?
>>
>>
> Bruce,
>
> I don't think I und
John Miles wrote:
I have a 5334B and looking at the same signal it seems more stable. From
memory (I haven't tried it recently) the 5370 had 3 or 4 unstable low
order digits. Even selecting high periods or sample size didn't seem to
remove noise out of two or three digits.
I never used a 5370 b
Actually, that may be more of a problem than you think. These originally ran
on a 1.35V mercury battery. A 1.5V alkaline cell can overdrive the tuning fork
causing the watch to run fast or not at all.
The watch may be able to be adjusted to work with the modern battery or you
need to use
> I have a 5334B and looking at the same signal it seems more stable. From
> memory (I haven't tried it recently) the 5370 had 3 or 4 unstable low
> order digits. Even selecting high periods or sample size didn't seem to
> remove noise out of two or three digits.
>
> I never used a 5370 before, bu
Bruce Griffiths wrote:
What is the indicated std deviation of the delay between the STAR and
STOP inputs when connecting the rear panel 10MHz signal to both START
and STOP inputs using the STAR COM position of the channel mode switch?
Bruce,
I don't think I understand exactly how to measure
Brooke Clarke wrote:
Hi again Mike:
The IIR-2 satellite was launched in order to meet a deadline rather
than when it was truly fully operational. The L5 module is an add on
and can not run at full power. So this is not a representative of the
future sats.
First of all, it's the IIR-20(M). I
John Miles wrote:
On the 5370A part, I recently bought one cheap and it sort of works but
seems very noisey in its lower order digit readings; clean external ref
doesn't help. I haven't looked at obvious things like the power supply
yet, but I'm curious if the group has any thoughts of common pr
Bruce Griffiths wrote:
Bruce
Rex wrote:
Bruce,
I've never seen you post a new thread as a response to an existing,
unrelated thread, as you've done here. You are not the first to do
this, but I thought you might be aware of these subtleties.
I was being lazy.
How can you tell, look
> On the 5370A part, I recently bought one cheap and it sort of works but
> seems very noisey in its lower order digit readings; clean external ref
> doesn't help. I haven't looked at obvious things like the power supply
> yet, but I'm curious if the group has any thoughts of common problems to
>
Bruce
Rex wrote:
> Bruce,
>
> I've never seen you post a new thread as a response to an existing,
> unrelated thread, as you've done here. You are not the first to do
> this, but I thought you might be aware of these subtleties.
>
I was being lazy.
How can you tell, looking at the message source
I still have one I bought for around $125 or 150 in Hawail in 1966. I'm
sure with a fresh battery it wud still work.. I have the see-thru model.
Bob, K1REM
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on
Behalf Of Ulrich Bangert
Sent: Friday,
Bruce,
I've never seen you post a new thread as a response to an existing,
unrelated thread, as you've done here. You are not the first to do this,
but I thought you might be aware of these subtleties.
In the spirit of quasi-related posts...
On the 5370A part, I recently bought one cheap and
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