I just got a 5370A locally and am going through the performance
checks. Things are not as they should be. Is there someone who knows
this unit intimately who would be willing to help me off list?
Joe Gray
KA5ZEC
___
time-nuts mailing list -- time-nuts@f
The 5370A is gone, thanks to all interested. I have one more piece of TN
gear to get rid of; a Datum model 9150 Time Code Generator. 24V aircraft
chasssis type (can be mounted in aircraft). Has a 1 MHz crystal, day and
time LED display, 1,10,100k pps as well as several IRIG B output BNC's.
Working,
Joseph Gray wrote:
I just got a 5370A locally and am going through the performance
checks. Things are not as they should be. Is there someone who knows
this unit intimately who would be willing to help me off list?
Joe Gray
KA5ZEC
___
time-nuts mailin
Joseph Gray wrote:
> I just got a 5370A locally and am going through the performance
> checks. Things are not as they should be. Is there someone who knows
> this unit intimately who would be willing to help me off list?
>
> Joe Gray
> KA5ZEC
>
>
Joe
What do you have in the way of test gear?
A
12:47 AM
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] 5370A
I just got a 5370A locally and am going through the performance
checks. Things are not as they should be. Is there someone who knows
this unit intimately who would be willing to help me off list?
Joe Gray
K
Tim,
Thanks for the encouragement. I hope you get yours fixed as well.
Joe Gray
KA5ZEC
On Fri, Oct 9, 2009 at 11:26 PM, swingbyte wrote:
> Joseph Gray wrote:
>>
>> I just got a 5370A locally and am going through the performance
>> checks. Things are not as they should be. Is there someone who k
Bruce,
I have a 100MHz scope, DVM, frequency counter, signal generator, etc.
Sorry, no spec an. I wish I had one.
The first problem is that it fails the first performance test. Instead
of 100nS, I get about 10nS and that slowly increases to about 12nS.
This is with the unit already warmed up and
It looks like I have a bad BNC on the front panel. After inspecting
the insides, I powered it up again. I got 104nS. Wiggling the BNC, it
went back to 12nS. I tried another coax - same problem. Before I tear
the front panel off, I'll see if I can find in the manual what I have
to adjust to get it t
Joe
Just be careful no to break the plastic handles off the boards.
The board retention force can be quite high.
Bruce
Joseph Gray wrote:
> Bruce,
>
> I have a 100MHz scope, DVM, frequency counter, signal generator, etc.
> Sorry, no spec an. I wish I had one.
>
> The first problem is that it fai
Bruce,
Thanks for the tip. I was very careful. Only one board was really
stuck. I left it alone for now.
Just for the heck of it, I did a few more steps in the Chapter 4
Operation Verification. As I said, discounting the bad BNC, step 13
reads aproximately 103.6nS, so I continued.
Steps 14, 15 a
Oh, one last question for the night. I noticed that the CPU board has
an emply ROM socket. I assume this is normal?
OK, let's make it two questions. While I'm working on this thing,
should I pull the EPROMS and ROMS and read them? I've heard of EPROMS
going bad in some other old equipment (maybe i
> Bruce,
>
> Thanks for the tip. I was very careful. Only one board was really
> stuck. I left it alone for now.
>
> Just for the heck of it, I did a few more steps in the Chapter 4
> Operation Verification. As I said, discounting the bad BNC, step 13
> reads aproximately 103.6nS, so I continued.
> Oh, one last question for the night. I noticed that the CPU board has
> an emply ROM socket. I assume this is normal?
>
> OK, let's make it two questions. While I'm working on this thing,
> should I pull the EPROMS and ROMS and read them? I've heard of EPROMS
> going bad in some other old equipm
>
> > Oh, one last question for the night. I noticed that the CPU board has
> > an emply ROM socket. I assume this is normal?
Yes, and you can use it to eliminate the ROM board altogether if desired.
See the .txt and .jpg files in the directory I mentioned earlier.
-- john, KE5FX
_
John,
Trigger levels are set to "Preset" for most steps. In step 18, I
verified that Preset is 0V and the Level voltage varied from
aproximately -1.3 to +0.6 volts. The manual specifies "approximately
-1.3 to +0.5 volts."
In step 15, the standard deviation was bouncing around between about
36-57p
I keep thinking of things instead of going to bed.
In the 5370A manual, the ops verification of the HPIB port requires an
old HP computer and a program on tape. Needless to say, I don't think
I'm going to come across either of these items. So, has anyone managed
to duplicate that test with modern
- Original Message -
From: "Joseph Gray"
To: "Discussion of precise time and frequency measurement"
Sent: Saturday, October 10, 2009 5:46 AM
Subject: [time-nuts] 5370A
I just got a 5370A locally and am going through the performance
checks. Things are not as they should
Joe
You can check a lot of the functionality from the front panel.
Make sure that it works well using the front panel controls before
checking that the HPIB interface works.
To check the HPIB functionality you will need an HPIB/GPIB interface for
your PC.
It is easy to duplicate the tests done by
...
Best,
Greg
- Original Message -
From: "Joseph Gray"
To: "Discussion of precise time and frequency measurement"
Sent: Saturday, October 10, 2009 3:14 AM
Subject: Re: [time-nuts] 5370A
John,
Trigger levels are set to "Preset" for most steps. In ste
ulse generators (from Boblingen
Division).
- Original Message -
From: "Roy Phillips"
To: "Discussion of precise time and frequency measurement"
Sent: Saturday, October 10, 2009 4:08 AM
Subject: Re: [time-nuts] 5370A
Hi Joe
I have a similar problem so I would b
One thing to note, the 5370A has a slim line relay (K1) in the power supply
that switches all of the voltages on... it is there for the crystal oscillator.
I had one that didn't produce enough contract pressure to reliably switch on all
of the voltages, and would quit if you bumped it lightly. I
recise time and frequency measurement"
Sent: Saturday, October 10, 2009 4:24 PM
Subject: Re: [time-nuts] 5370A
Roy,
The HP 5370A rear mounted heat-sink typically heats up to around 61
degrees
C. This is very hot to the touch, so I suspect your unit's temperature is
normal (unl
continue to deteriorate, there comes a
> time when the only solution is to replace the bad I.C.(s).
>
> Hopefully your unit isn't so afflicted. ...Just covering the bases...
>
> Best,
> Greg
>
>
>
> - Original Message -
> From: "Joseph Gray&q
>
> - Original Message -
> From: "Roy Phillips"
> To: "Discussion of precise time and frequency measurement"
>
> Sent: Saturday, October 10, 2009 4:08 AM
> Subject: Re: [time-nuts] 5370A
>
>
> Hi Joe
> I have a similar problem so I wou
t-end. If
you have that problem, typically it will be in one channel only, although it
could of course be in both.
Greg
- Original Message -
From: "Joseph Gray"
To: "Discussion of precise time and frequency measurement"
Sent: Saturday, October 10, 2009 12:42 P
; could of course be in both.
>
> Greg
>
>
> - Original Message -
> From: "Joseph Gray"
> To: "Discussion of precise time and frequency measurement"
>
> Sent: Saturday, October 10, 2009 12:42 PM
> Subject: Re: [time-nuts] 5370A
>
>
> Greg,
>
be a good idea to run the instrument too long without
its top cover.
Greg
- Original Message -
From: "Joseph Gray"
To: "Discussion of precise time and frequency measurement"
Sent: Saturday, October 10, 2009 1:55 PM
Subject: Re: [time-nuts] 5370A
The heatsink on m
en
>> Division).
>>
>>
>> - Original Message -
>> From: "Roy Phillips"
>> To: "Discussion of precise time and frequency measurement"
>>
>> Sent: Saturday, October 10, 2009 4:08 AM
>> Subject: Re: [time-nuts] 5370A
&
t; P.S. I agree that the rear mounted heat sinks of most other HP equipment
>>> run
>>> significantly cooler. The models that run so hot to the touch are the
>>> 5370A/B, 5359A, and many of the legacy HP pulse generators (from
>>> Boblingen
>>> Division).
>>
ments.
Best,
Greg
- Original Message -
From: "Joseph Gray"
To: "Discussion of precise time and frequency measurement"
Sent: Saturday, October 10, 2009 2:23 PM
Subject: Re: [time-nuts] 5370A
Greg,
Yes, the trigger levels are near zero when the LEDs are flashing.
u can still correct for it by doing the A3/A4 input adjustments.
>
> Best,
> Greg
>
>
> - Original Message -
> From: "Joseph Gray"
> To: "Discussion of precise time and frequency measurement"
>
> Sent: Saturday, October 10, 2009 2:23 PM
&g
Greg Burnett wrote:
> Joe,
>
> I think 1 o'clock (instead of 12 o'clock) might still be OK and/or typical?
> Maybe some other 5370A users can tell us where their Trigger Level pots are
> pointing when centered for triggering on a weak signal. (The pots point to
> 12 o'clock on my 5370B, but I c
n
>>>> significantly cooler. The models that run so hot to the touch are the
>>>> 5370A/B, 5359A, and many of the legacy HP pulse generators (from
>>>> Boblingen
>>>> Division).
>>>>
>>>>
>>>> - Original Message --
> I plan on doing the A3/A4 adjustments. I just don't know where I'm
> going to get a pulse generator or the fancy scope with the 1GHz
> sampling plugin. Not the type of equipment on your average test bench.
You won't need any exotic gear for the DAC voltage adjustments or the A3/A4
input assembl
John,
Thanks for the good advice. I definitely need to pull the front panel
to replace the flakey BNC. After that, I'll do what I can with the
A3/A4 adjustments. I just took another look at what I was doing last
night and the two input channels do need adjusting. The B channel is
worse.
I have a
Dear All,
I have problems accessing the 5370A manual on the Agilent website?!
Accessing the 5370B manual is nor problem. Any suggestions?
Thanks, Jeroen
--
Ing. Jeroen Bastemeijer
Delft University of Technology
Department of Electrical Engineering
Electronic Instrumentation Laboratory
Mekelwe
Hello Time-Nuts,
once again a question to the 5370 experts:
After some time of operation (hours...) my 5370A starts to become noisy.
This can be seen best when teeing the 10 MHz REF OUT to IN A nnd IN B,
choosing TI and setting STD DEV, 1k samples. When everything works well,
the displayed va
The 5370 cooling fan blows across the chassis directly onto the input board.
The switches are basically gold plated strips on springy material that slide on
the circuit board. They are open to the world and not sealed. Dust and fluff
accumulates on the board and into the switches. You can
Hi
How much of the 5370A was directly carried over into the 5370B?
Bob
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and follow the instructions there.
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 pa
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 stabil
Yes, I replace the standard HP fan with a MUCH quieter one. I get mine from
a local surplus shop. It is made by AAVID. it draws 120 mA at 12V and I run
it off the 10V supply (which is somewhat over 10V).
I don't have one handy to get the part number. They also have a 160 mA model
par
back to the original issue front panel
One thing I have had success with is emailing some of the
bigger EBay instrument sellers and asking if they have
a parts unit. It helps of you are/were a regular customer.
I repaired a 3325A that needed some buttons, a bottom panel
etc. I asked and was offer
Hello everyone,
This is my first posting to Time-Nuts so please bear
with me if I don't have the proper etiquette.
I guessed that many members here have the
HP5370A(B) counters.
I have 1 5370A and 2 5370B.
For some weird set of circumstances,
all three units failed withing 1 week.
The problem
Jeroen Bastemeijer wrote:
> Dear All,
>
> I have problems accessing the 5370A manual on the Agilent website?!
> Accessing the 5370B manual is nor problem. Any suggestions?
>
> Thanks, Jeroen
>
>
Jeroen
Try
http://www.g8wrb.org/data/HP/HP5370A.pdf
Bruce
__
Bruce,
Thank you!
Best regards, Jeroen
Dr Bruce Griffiths wrote:
>Jeroen Bastemeijer wrote:
>
>
>>Dear All,
>>
>>I have problems accessing the 5370A manual on the Agilent website?!
>>Accessing the 5370B manual is nor problem. Any suggestions?
>>
>>Thanks, Jeroen
>>
>>
>>
>>
>Jeroen
>
>
The 5370A (and B) service manual is also at www.ko4bb.com/ham_radio/Manuals
Didier KO4BB
Jeroen Bastemeijer <[EMAIL PROTECTED]> wrote:
> Dear All,
>
> I have problems accessing the 5370A manual on the Agilent website?!
> Accessing the 5370B manual is nor problem. Any suggestions?
>
> Th
Thank you, Didier.
I had a quick look the manual looks the same as the one on the website
of Beuce.
Best regards, Jeroen
Didier Juges wrote:
>The 5370A (and B) service manual is also at www.ko4bb.com/ham_radio/Manuals
>
>Didier KO4BB
>
> Jeroen Bastemeijer <[EMAIL PROTECTED]> wrote:
>
>
That may be where I got it from. I remember Beuce's web site not being always
available. I did email him originally because I could not download the manual
for some reason when I bought my first 5370A.
Good luck with your 5370! Both my units have the bad socket syndrom, and it is
getting to the
> Good luck with your 5370! Both my units have the bad socket syndrom,
> and it is getting to the point where I have pretty much decided to
> replace all the sockets.
Many years ago, I worked on a system full of chips in sockets and the
associated reliability problems. Standard prototype stuff.
Well, one thing for sure, in both my units, the chips are not anywhere near
ready to fall off. I need a crow bar to take them out...
Same thing with the PWBs themselves, the card edge connectors are extremely
tight, that's one reason I am puzzled by the problems, there seems to be plenty
of con
Didier Juges wrote:
> Well, one thing for sure, in both my units, the chips are not anywhere near
> ready to fall off. I need a crow bar to
> take them out...
>
> Same thing with the PWBs themselves, the card edge connectors are extremely
> tight, that's one reason I am puzzled by
> the proble
Hi Chuck,
Thanks for the tip. That's got to be the problem. I will take the CPU card out
of the worst offender tonight and look under the magnifier.
Didier KO4BB
Chuck Harris <[EMAIL PROTECTED]> wrote:
>
>
> Didier Juges wrote:
> > Well, one thing for sure, in both my units, the chips a
if anyone is looking for a 5370, there is one on ebay that is currently
listed for $29+shipping...
http://www.ebay.com/itm/HP-Agilent-5370A-Universal-Time-Interval-Counter-/160714650831?pt=LH_DefaultDomain_0&hash=item256b56f4cf
No financial interest, but that's a lot less than I paid for mine! ;)
Hi
There is a very extensive calibration / alignment process for the 5370. It
sounds
a lot like your box was set up “cold” rather than after a proper warmup. There
is a
lot of “stuff” in there, so picking out exactly which adjustment is drifting is
going to
be a guessing game.
Bob
> On Oct
Front panel, chassis, motherboard, and power supply appear to be the same.
The CPU, ROM, and RAM boards were made into a single board. There were
some changes to the counting circuitry to make it more production friendly.
The whole counter was sped up so that it could read at a somewhat higher
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 wrote:
Front panel, chassis, motherboard, and power supply appear to be the
same.
The CPU, ROM, and RAM boards were made into a single board.
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 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 Griffit
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
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 list
boun...@febo.com] On
Behalf Of paul swed
Sent: Tuesday, March 09, 2010 8:49 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] 5370A vs 5370B
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
ssage -
From: "Bob Camp"
To: "'Discussion of precise time and frequency measurement'"
Sent: Tuesday, March 09, 2010 10:08 AM
Subject: Re: [time-nuts] 5370A vs 5370B
Hi
Ok, the rest of the story:
I picked up a 5370B for less than the price of the 10811 inside it.
sion of precise time and frequency measurement
Subject: Re: [time-nuts] 5370A vs 5370B
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
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 i
on Latham
Sent: Tuesday, March 09, 2010 1:04 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] 5370A vs 5370B
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
sion of precise time and frequency measurement
Subject: Re: [time-nuts] 5370A vs 5370B
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"
To: "'
2010 2:00 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] 5370A vs 5370B
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'l
ghput considerably and could sell the upgrade to all of us
with 5370's. I would not be surprised if a PIC could do the task. . .
Demian
Date: Tue, 9 Mar 2010 16:56:41 -0500
From: "Bob Camp"
Subject: Re: [time-nuts] 5370A vs 5370B
To: "'Discussion of precise
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 5370
de to all of us
with 5370's. I would not be surprised if a PIC could do the task. . .
Demian
Date: Tue, 9 Mar 2010 16:56:41 -0500
From: "Bob Camp"
Subject: Re: [time-nuts] 5370A vs 5370B
To: "'Discussion of precise time and frequency mea
> 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 pac
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 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 arm, and
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 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
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
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 wrote:
> 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 las
ed, 10 Mar 2010 00:03:04 +
From: Mark Sims
Subject: [time-nuts] 5370A vs 5370B
To:
Message-ID:
Content-Type: text/plain; charset="iso-8859-1"
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
ment
> Subject: Re: [time-nuts] 5370A vs 5370B
>
>
> 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 wrote:
>
> > Hi
> >
> > Ok, the trigger level pots
g through the manual at that point.
>
> -- john, KE5FX
>
>> -Original Message-
>> From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on
>> Behalf Of paul swed
>> Sent: Tuesday, March 09, 2010 5:50 PM
>> To: Discussion of precise time and
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 fo
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 Ca
s it would
> be a simple task to create the header with chip. I don't know if the 5370B
> would be as easy to substitute.
> -Demian
>
>
>
>
>
>
> Date: Wed, 10 Mar 2010 00:03:04 +
> From: Mark Sims
> Subject: [time-nuts] 5370A vs 5370B
>
: time-nuts@febo.com
Subject: [time-nuts] 5370A vs 5370B
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 continu
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, t
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
On 3/9/2010 10:09 PM, "John Allen"
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 bench, but it won't happen soon.
-
Mark Sims wrote:
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.
Measuring it's own time-base is expected to give value not exactly
on-beat. Internal cross-talk with the interna
Hi
Yes indeed, the period was measured with the two channels in the com mode and
the reference into one of them. I hadn't considered the trigger offset issues
and was expecting something sub-100 ps rather than 500 ps. Obviously I need to
spend some "quality time" with this beast. Now I gotta fi
Bob Camp wrote:
Hi
Yes indeed, the period was measured with the two channels in the com mode and
the reference
into one of them. I hadn't considered the trigger offset issues and was
expecting something
sub-100 ps rather than 500 ps. Obviously I need to spend some "quality time"
with this bea
At 4:10 PM + 3/10/10, Mark Sims wrote:
Yes, I replace the standard HP fan with a MUCH quieter one. I get
mine from a local surplus shop. It is made by AAVID. it draws 120
mA at 12V and I run it off the 10V supply (which is somewhat over
10V).
Before getting all whiny about overheati
One trick I always use to quiet down a rowdy fan is to replace the
mounting screws with rubber mounts. This isolates the fan's mechanical
vibrations from the chassis. The difference is audible - even with a
good fan. I salvaged some mounts from IBM machines that work great.
Most of the big
time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Magnus Danielson
Sent: Wednesday, March 10, 2010 7:48 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] 5370A vs 5370B
Bob Camp wrote:
> Hi
>
> Yes indeed, the period was measure
Ed Palmer wrote:
One trick I always use to quiet down a rowdy fan is to replace the
mounting screws with rubber mounts. This isolates the fan's mechanical
vibrations from the chassis. The difference is audible - even with a
good fan. I salvaged some mounts from IBM machines that work great.
Subject: Re: [time-nuts] 5370A vs 5370B
Ed Palmer wrote:
> One trick I always use to quiet down a rowdy fan is to replace the
> mounting screws with rubber mounts. This isolates the fan's mechanical
> vibrations from the chassis. The difference is audible - even with a
> good
Bob Camp wrote:
Hi
Fanless Atom motherboard / solid state disk / wall wart power supply ... DVD
is still the main source of noise.
This was far from that. It is a AMD PHENOM II X4 90SE 2,5GHz CPU with 8
SAMSUNG ECOGREEN F2 1,5TB SATA disks is certainly not tailored in such a
fashion. The Fr
Hi
Ok, I got enough time to play a bit more with the 5370B today. Here's what I
found (all running on the internal standard):
If I take the gate time out to 1 second, the frequency display reads as it
should.
If I look at the standard deviation on various samples of period I get some
interes
Last week I bought a very clean 5370B, in near new condition (missing OCXO but
I have a spare one).
It has a HP tag on the top edge of the rear frame, under the top cover, which
says:
Date 12 09 97 5370A to 5370B by 28457
The serial number is 2116A01177. The front panel template is marked 5370B
> For some weird set of circumstances,
> all three units failed withing 1 week.
Were they running at the time? Any chance
you overloaded the overly sensitive inputs with
an unattenuated 1PPS pulse?
> The 5370B's were much worse off.
> It seems that they both suffer from failures
> in the U24,25,2
At 9:58 PM -0400 9/12/05, xaos wrote:
The 5370B's were much worse off.
It seems that they both suffer from failures
in the U24,25,26 chips on the Arming board.
How did you determine this?
Unfortunately, the two units are not identical
and I cannot cannibalize one to fix the other.
What I ca
In message <[EMAIL PROTECTED]>, David Forbes writes:
>These EECL chips are indeed odd beasts. No data via Google; not in
>the Motorola book from 1980; I'd guess that this is a completely
>in-house logic family.
I don't think that conclusion is justified, ECL logic was always
rather special beas
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