Hi
Power supply noise would be the first thought.
Next up would be grounding inside the Thunderbolt (card to case, connectors to
case).
Bob
On Mar 9, 2010, at 7:32 AM, Christophe Huygens wrote:
Hi,
I noticed several vendors on Ebay have the t-bolt on sale.
However, the once showing
This is with the power supply as provided by TAPR so should be ok.
Xtof.
On 09/03/10 13:44, Bob Camp wrote:
Hi
Power supply noise would be the first thought.
Next up would be grounding inside the Thunderbolt (card to case, connectors to
case).
Bob
On Mar 9, 2010, at 7:32 AM, Christophe
Hi,
I noticed several vendors on Ebay have the t-bolt on sale.
However, the once showing their own PN plots seem to get only
-115, -120 dBc/Hz at 100Hz. Yet,
http://www.leapsecond.com/pages/tbolt/noise.htm seems
to have mucht better results: up to -150 depending on
power supply.
By multiplying
I don't think thats true.
There would be a lot of common parts so the question is what are you looking
for?
On Tue, Mar 9, 2010 at 7:47 AM, Bob Camp li...@rtty.us wrote:
Hi
So a parts donor 5370B is a donor for 5370B's and not so much for a 5370A.
Bob
On Mar 8, 2010, at 11:37 PM, Bruce
I think the TAPR supply was selected on cost and availabilty, not perfomance.
I seem to recall reliability problems too. I'd test it with a good linear PSU
before putting blame on the Tbolt!
Robert G8RPI.
--- On Tue, 9/3/10, Christophe Huygens christophe.huyg...@cs.kuleuven.ac.be
wrote:
Hi
So a parts donor 5370B is a donor for 5370B's and not so much for a 5370A.
Bob
On Mar 8, 2010, at 11:37 PM, Bruce Griffiths wrote:
The input amplifiers also differ.
The linear input voltage range of the 5370B input amplifiers is greater than
that of the 5370A.
Bruce
Chuck Harris
Bob Camp wrote:
Hi
So a parts donor 5370B is a donor for 5370B's and not so much for a 5370A.
It should be decided on a board-for-board level. Several boards are just
the same, so it would be no problem.
Cheers,
Magnus
___
time-nuts mailing
Hi
Ok, the rest of the story:
I picked up a 5370B for less than the price of the 10811 inside it. The unit
powers up and appears to function at some level. All of the front panel
knobs are either busted or sheared off. Switches and buttons all seem to be
there and function (2 minute quick
Hi
How are you multiplying it to 1 GHz and checking it?
I've seen multipliers that have issues beyond about -130 at 100 Hz. It's not
common, but it can happen.
--
The supply provided by TAPR is a pretty basic unit. It would not surprise me
if some were better than others. They
Why would flicker noise be a concern if there is no dc current flowing
in the switches?
Bruce
Hi Bruce,
Does it matter if the current is DC or AC? I expect to see +/-20 mA current
due to the signal level.
Clay
From: Bob Camp li...@rtty.us
Subject: Re: [time-nuts] 10 MHz reference
Hi,
I am using an ADF4107 and a Crystek resonator, with a LBW of
a few 100 Hz. It behaves perfect outside the loop, but inside the
loop it is too noisy (not too important for my application, but
just curious).
I ll try to measure the Thunderbolt directly at 10Mhz, but the
my HP 11729C needs
Hi
Can you simply turn off the oscillator part of the OCXO?
In other words, leave the oven on and kill the RF at the source.
Bob
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of life speed
Sent: Tuesday, March 09, 2010 12:22 PM
To:
Hi
I think you will find that the noise floor of the ADF4107 (dividers and
phase detector) is a bit higher than -150 at 100 Hz offset at 10 MHz. It
should get you past the -120 level though. That's still much better than you
are seeing.
Indeed -120 is not what figure 15 on page 8 of the
Hi Bob: sounds as if it just had a hard bump, meaning that all the boards
and connectors need reseating. I had an Hp device with a tiny crack in a pc
trace on the motherboard, but by golly I found it. Hope the B doesn't prove
to be a sequential vortex :-)
Don
- Original Message -
Hi
I'm about 90% sure I'm going to hang on to the counter. It may wind up with
a bunch of fixed level inputs on it, but for the price - I'll live with
that. Other than the blow to the front panel it seems to be in ok shape.
If I do keep it, tearing it open and checking all the internals is
Bob Camp wrote:
Hi
I'm about 90% sure I'm going to hang on to the counter. It may wind up with
a bunch of fixed level inputs on it, but for the price - I'll live with
that. Other than the blow to the front panel it seems to be in ok shape.
If I do keep it, tearing it open and checking all the
shucks, you can always get out the good ol' dremel and score some grooves in
the broken pots-then use a screwdriver...
Don
- Original Message -
From: Bob Camp li...@rtty.us
To: 'Discussion of precise time and frequency measurement'
time-nuts@febo.com
Sent: Tuesday, March 09, 2010
Yes, high frequency AC current doesn't usually result in flicker noise.
Bruce
life speed wrote:
Why would flicker noise be a concern if there is no dc current flowing
in the switches?
Bruce
Hi Bruce,
Does it matter if the current is DC or AC? I expect to see +/-20 mA current
due to
Hello,
J Anyone here have any experience with these masers?
J In particular the VCH-1005A?
J I have been tasked to look after a number of these units and am currently
J going through the manuals (which are in English but written by a Russian, so
J they can be challenging :-)
Do you have
From: Bob Camp li...@rtty.us
Subject: Re: [time-nuts] Realistic Tbolt phase noise
Hi
I think you will find that the noise floor of the ADF4107 (dividers and
phase detector) is a bit higher than -150 at 100 Hz offset at 10 MHz. It
should get you past the -120 level though. That's still much
Yuri Ostry wrote:
Hello,
J Anyone here have any experience with these masers?
J In particular the VCH-1005A?
J I have been tasked to look after a number of these units and am currently
J going through the manuals (which are in English but written by a Russian, so
J they can be challenging :-)
Hi,Does anyone have a data sheet for the Oscilloquartz B1325 (or B1326 12V
version) OXCO?I have a 4.096MHz example and only basic data. I know it has a
dewar for insulation but don't know the crystal cut or if it's a single or
double oven. It dates from the early to mid 1980's
Thanks in
Fellow time-benders,
Does anyone happen to have the tech manual for the old Datum 9200-209
reader/display? It's currently set to decode IRIG-E at 100Hz, and I need
to reconfigure it (if possible) for IRIG-B at 1kHz.
Thanks.
Bruce Lane, Owner Head Hardware Heavy,
Blue Feather
Hi
Assuming there's enough of the pot left, (as in the pot still works) that's
very likely what I'll do.
Bob
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Don Latham
Sent: Tuesday, March 09, 2010 2:21 PM
To: Discussion of precise
Hi
The price was a bit above that, but still in the good deal range. I think
I'll be popping the case open this evening.
Bob
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Magnus Danielson
Sent: Tuesday, March 09, 2010 2:00 PM
To:
I haven't exhaustively tested the ADF4107 but I have played with the ADF4002
recently. I haven't been able to come within several dBc/Hz of its rated
noise level. In one test, at 100 Hz from an 80 MHz carrier, I've seen
about -118 dBc/Hz from the ADF4002 when fed by 10 MHz with -145 dBc/Hz at
Boy I have several 9200s I believe its a separate board I think
No manual
On Tue, Mar 9, 2010 at 4:34 PM, Bruce Lane kyr...@bluefeathertech.comwrote:
Fellow time-benders,
Does anyone happen to have the tech manual for the old Datum
9200-209
reader/display? It's currently set to
Hi John,
we have a new 100MHz board (FireFly-IIA-100MHz) that uses an ADF4002 to
generate 100MHz from the 10MHz internal OCXO.
The VCXO we use is rated at better than 100dBc at 100Hz.
The 10MHz reference achieves typ. -148 dBc at 100Hz.
We measured -115dBc/Hz at 100MHz at 100Hz offset in
Hi:
For some time I've considered surrounding a free running 32678 Hz
oscillator (like a Dallas 32khz, or one of the newer Maxim units) with
thermal mass and insulation in order to get the time constant into the
range of some days. To get a feel for it a simple experiment shows that
a half
Quoth Brooke Clarke at 10/03/10 10:22...
...like a Dallas 32khz, or one of the newer Maxim units...
There's a Maxim part to supersede the DS32kHz? I know that my regular
vendors [Farnell, Soanar, Futurlec] in Australia don't stock the
DS32kHz, which makes them mega-expensive to acquire.
I've had the pleasure of fixing way too many 5370A and 5370B front panels.
It's been a while so these musings may be clouded... also beware of the two
or three different front panel designs. Also there are hybrid 5370A's out
there with 5370B front ends.
There are 4 pots on the front
Brooke Clarke wrote:
Hi:
For some time I've considered surrounding a free running 32678 Hz
oscillator (like a Dallas 32khz, or one of the newer Maxim units) with
thermal mass and insulation in order to get the time constant into the
range of some days. To get a feel for it a simple
Bruce Griffiths wrote:
Brooke Clarke wrote:
Hi:
For some time I've considered surrounding a free running 32678 Hz
oscillator (like a Dallas 32khz, or one of the newer Maxim units)
with thermal mass and insulation in order to get the time constant
into the range of some days. To get a feel
I got an almost perfect 5370A some years ago for less than $100. It had one
dead input. I discovered that those input devices were essentially
unobtanium so I went shopping for a substitute. I found a Maxim chip that
seems to work as well as the original comparator, possibly slightly better.
I
Hi
One of the trigger level pots is stuck at the 2 V end of it's travel. That's
making checking things a little difficult.
The 5345 inputs were pretty easy to blow as I recall.
Bob
On Mar 9, 2010, at 7:03 PM, Mark Sims wrote:
I've had the pleasure of fixing way too many 5370A and 5370B
Why bother, you can replace the entire box apart from the input signal
conditioning with an FPGA and a pair of high resolution time interval
interpolators (eg 2 ADCs per interpolator, or a TAC circuit like those
used by Wavecrest.).
Bruce
Demian Martin wrote:
I got an almost perfect 5370A
The display rate pots is particularly useless. You can just
hardwire it to max.
The only case I've seen where that's an issue is when using the counter over
GPIB, free running in talk-only mode. If I run it with the Prologix
Ethernet adapter, which turns each reading into its own TCP/IP
Hi
Ok, the trigger level pots are bent but functional. The one that was stuck
works after a bit of readjustment of the knob.
All three inputs (ext arm, and the two channels) blink when I put the 10 MHz
into them. The two with the working pots behave as expected as the pot is
turned (trigger
Bob how long has it been on
I think it needs to be stable like about 30 minutes
On Tue, Mar 9, 2010 at 8:37 PM, Bob Camp li...@rtty.us wrote:
Hi
Ok, the trigger level pots are bent but functional. The one that was stuck
works after a bit of readjustment of the knob.
All three inputs (ext
I think it has to warm up for about 30 minutes
Seem to recall interpolators maybe not just seems like that
On Tue, Mar 9, 2010 at 8:37 PM, Bob Camp li...@rtty.us wrote:
Hi
Ok, the trigger level pots are bent but functional. The one that was stuck
works after a bit of readjustment of the
Hi
I didn't leave it on for very long. IIt would not surprise me if there's some
drift that's occurred. It was last calibrated in 2006.
Bob
On Mar 9, 2010, at 8:48 PM, paul swed wrote:
Bob how long has it been on
I think it needs to be stable like about 30 minutes
On Tue, Mar 9, 2010 at
If you are using the internal oven give it time
The old brain says there may have been another circuit that also needed
time.
On Tue, Mar 9, 2010 at 8:52 PM, Bob Camp li...@rtty.us wrote:
Hi
I didn't leave it on for very long. IIt would not surprise me if there's
some drift that's occurred.
Being naïve I didn't know the HP custom chip would be difficult to
substitute. Since it was blown and not available I went searching and found
a Maxim chip (MAX9691 I think) that would work on paper. It is surface mount
and I managed to find a header that fit the HP socket and some careful
wiring
It should be good to go right away, if working properly.
If it were measuring an independent 10 MHz source at 99.998xxx MHz I would
suspect the thermal fuse in the 10811.. but if it's measuring its own
reference, I'm not immediately sure what would be up with that. It would be
time to start
Hi
Well I popped the top off of the beast. As far as I can tell, everything is
there and there are no big burn marks on any of the boards. Judging from the
edges of the cards, they have not been out of their sockets very often.
The alignment procedure in the manual is pretty straightforward
By god I thought it had interpolators.
Good to stay clear of them
That said let the whole thing warm up.
Maybe an hour even. See if your numbers don't come closer when reading the
internal oscillator to itself. If its good then leave the interpolators
alone.
On Tue, Mar 9, 2010 at 10:27 PM, Bob
99.95 ns is a typical number for the period reading at minimum gate time. Set
the gate time to 1 sec. My 5370A shows 99.999 999 9650 +/- 50 at 1 sec gate
time.
From my experience it can take at least a couple of months of continuous
operation for the oscillator in an unused 5370 to
a schmartcard will let you wire it any way you need, and you don't have to
have a board made.
Don
Demian Martin
Being naïve I didn't know the HP custom chip would be difficult to
substitute. Since it was blown and not available I went searching and
found
a Maxim chip (MAX9691 I think) that
Hi Mark - do you have a source or part number for the fan? I seem to remember
that the manuals says 35 or 37 cfm.
Thanks,
John K1AE
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf
Of Mark Sims
Sent: Tuesday, March 09, 2010 11:30 PM
To:
my gosh, put on a nice external 10 mhz reference like from your standard
and test against itself :-)
Bob Camp
Hi
Well I popped the top off of the beast. As far as I can tell, everything
is there and there are no big burn marks on any of the boards. Judging
from the edges of the cards, they
Bob,
I think you'll find that the test mode you're describing results from
is setup using A as start B as stop and the period measurement
is for 1 period.
The resulting 99.x reading has rather wide limits since both channel
trigger level uncertainties are included in the measurement. Unless
you
I have a question for owners of the HP 5372A (and probably 5371A) Time
Interval Analyzer.
Is the fan on the back blowing out or sucking in?
I was looking at mine to see about replacing the fan with a quieter one
and I was surprised to see that mine is sucking in. This doesn't make
sense to
Paul Boven wrote:
Hi Tom, everyone,
Tom Van Baak wrote:
See: http://www.leapsecond.com/museum/pulsar for some
pulsar ADEV stability plots and links to many research papers
with all the details.
Your page starts with the question if it was possible for an amateur to
receive pulsar signals?.
On 3/9/2010 10:09 PM, John Allen j...@pcsupportsolutions.com
wrote:
Hi Mark - do you have a source or part number for the fan? I seem to remember
that the manuals says 35 or 37 cfm.
Without a pressure drop, cfm is is not sufficient to find an adequate fan.
I can put a 5370A/B on a flow
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