10811 warmup
Didier,
My experience with 4 10811's with widely separated serial numbers is consistent with your
numbers below. Between 6 and 8 minutes of warm up from ambient (18C) and they're stable at the
target frequency as measured with a recently calibrated 5328A (one without a 10811 - since
remediated!)
The recent bad unit I bought on ebay behaved similarly - it warmed up and within 10 minutes it
had stabilized around 9,999,915.
It is adjustable between about 9,999,900 and 9,999,920 or so using the adjustment capacitor
through the hole in the case. EFC seems to function correctly as well with a little over 1Hz
of adjustability with +-5 V.
As has been suggested, it must be some kind of test unit (or perhaps one that failed QA?)
I replaced it with one from AST Global - they had a great return policy, shipped fast and
packed well.
In any case, I've retired the bad one as a marker generator at 9.9999 MHz.
Mark
Message: 1
Date: Fri, 19 Jan 2007 22:53:28 -0600
From: Didier Juges didier@cox.net
Subject: Re: [time-nuts] Bad batch of HP10811's
To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Message-ID: 45B1A048.9090207@cox.net
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Warmup data on the HP 10811:
Here is some data collected on the internal HP 10811 timebase in my HP
5370A counter, which had been turned off and plugged off for about 3 days.
21:39:25, 9999798.6
21:39:35, 9999806.0
21:39:46, 9999822.6
21:39:55, 9999836.8
21:40:06, 9999853.2
21:40:15, 9999866.8
21:40:26, 9999881.7
21:40:35, 9999892.4
21:40:46, 9999904.1
21:40:56, 9999913.1
21:40:58, 9999915.2
21:41:07, 9999923.0
21:41:16, 9999930.1
21:41:25, 9999936.5
21:41:36, 9999944.0
21:41:46, 9999949.3
21:41:55, 9999954.3
21:42:06, 9999959.9
21:42:15, 9999964.0
21:42:26, 9999968.6
21:42:35, 9999971.8
21:42:45, 9999975.2
21:42:54, 9999977.9
21:43:05, 9999981.0
21:43:17, 9999983.9
21:43:26, 9999985.9
21:43:35, 9999987.8
21:43:46, 9999990.0
21:43:55, 9999991.3
21:44:07, 9999992.9
21:44:16, 9999994.0
21:44:25, 9999994.9
21:44:36, 9999996.1
21:44:45, 9999996.9
21:44:56, 9999997.7
21:45:06, 9999998.3
21:45:15, 9999998.9
21:45:17, 9999999.0
21:45:19, 9999999.1
21:45:21, 9999999.2
21:45:24, 9999999.3
21:45:26, 9999999.4
21:45:36, 9999999.7
21:45:45, 9999999.8
21:45:56, 9999999.9
21:46:05, 9999999.9
21:46:08, 9999999.9
21:46:10, 10000000.0
After that, the display was a stable 10,000,000.0 for the next 15
minutes (one reading was 10,000,000.1), then I stopped the data collection.
The counter used was the HP 5334B with the Thunderbolt as external
reference.
Ambient temperature: about 22 degrees C (cool)
Bottom line: about 200 Hz from a cold start and about 7 minutes to
within 0.1 Hz of final frequency.
Didier KO4BB
On this unit, I suspect the oven was not at the correct operating
temperature. Thus, although it warmed up to some extent, it may
not have reached 80 degrees C. The real diagnostic would be to
slide it out of the case and look at the voltages on the thermistor
circuitry. However a crude check can be made by measuring the
oven current and comparing it to a good 10811. If it is substantially
lower, that would be a red flag. The fact that the frequency seems
to be fairly stable is no guarantee that you couldn't have the
wrong oven temperature. I have never heard of a 10811 with a properly
working oven that was that far off frequency. You need to realize
that crystals had to pass a frequency test before the lid was installed
on the crystal package. This was all done under automation. Thus it is
"impossible" for a crystal 100 Hz low to ever exist. And AFAIK, we
never made one on purpose.
Rick Karlquist N6RK
Mark Amos wrote:
Didier,
My experience with 4 10811's with widely separated serial numbers is
consistent with your
numbers below. Between 6 and 8 minutes of warm up from ambient (18C) and
they're stable at the
target frequency as measured with a recently calibrated 5328A (one without
a 10811 - since
remediated!)
The recent bad unit I bought on ebay behaved similarly - it warmed up and
within 10 minutes it
had stabilized around 9,999,915.
It is adjustable between about 9,999,900 and 9,999,920 or so using the
adjustment capacitor
through the hole in the case. EFC seems to function correctly as well
with a little over 1Hz
of adjustability with +-5 V.
As has been suggested, it must be some kind of test unit (or perhaps one
that failed QA?)
I replaced it with one from AST Global - they had a great return policy,
shipped fast and
packed well.
In any case, I've retired the bad one as a marker generator at 9.9999 MHz.
Mark
Message: 1
Date: Fri, 19 Jan 2007 22:53:28 -0600
From: Didier Juges didier@cox.net
Subject: Re: [time-nuts] Bad batch of HP10811's
To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Message-ID: 45B1A048.9090207@cox.net
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Warmup data on the HP 10811:
Here is some data collected on the internal HP 10811 timebase in my HP
5370A counter, which had been turned off and plugged off for about 3 days.
21:39:25, 9999798.6
21:39:35, 9999806.0
21:39:46, 9999822.6
21:39:55, 9999836.8
21:40:06, 9999853.2
21:40:15, 9999866.8
21:40:26, 9999881.7
21:40:35, 9999892.4
21:40:46, 9999904.1
21:40:56, 9999913.1
21:40:58, 9999915.2
21:41:07, 9999923.0
21:41:16, 9999930.1
21:41:25, 9999936.5
21:41:36, 9999944.0
21:41:46, 9999949.3
21:41:55, 9999954.3
21:42:06, 9999959.9
21:42:15, 9999964.0
21:42:26, 9999968.6
21:42:35, 9999971.8
21:42:45, 9999975.2
21:42:54, 9999977.9
21:43:05, 9999981.0
21:43:17, 9999983.9
21:43:26, 9999985.9
21:43:35, 9999987.8
21:43:46, 9999990.0
21:43:55, 9999991.3
21:44:07, 9999992.9
21:44:16, 9999994.0
21:44:25, 9999994.9
21:44:36, 9999996.1
21:44:45, 9999996.9
21:44:56, 9999997.7
21:45:06, 9999998.3
21:45:15, 9999998.9
21:45:17, 9999999.0
21:45:19, 9999999.1
21:45:21, 9999999.2
21:45:24, 9999999.3
21:45:26, 9999999.4
21:45:36, 9999999.7
21:45:45, 9999999.8
21:45:56, 9999999.9
21:46:05, 9999999.9
21:46:08, 9999999.9
21:46:10, 10000000.0
After that, the display was a stable 10,000,000.0 for the next 15
minutes (one reading was 10,000,000.1), then I stopped the data
collection.
The counter used was the HP 5334B with the Thunderbolt as external
reference.
Ambient temperature: about 22 degrees C (cool)
Bottom line: about 200 Hz from a cold start and about 7 minutes to
within 0.1 Hz of final frequency.
Didier KO4BB
time-nuts mailing list
time-nuts@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
I just got an email from Christopher this morning, saying he successful got
his TS2100 IRIG working with the ACE III receiver I sent him! I only wish I
had the same luck with my NTS-100.
The guy on eBay who I got the ACE IIIs from is: swampy-tom
I just noticed he has started listing them (I sent him a bunch of info
because he did not know what they were initially). He supposedly has a bunch
of these, so if you want to get them cheap just be patient as I'm sure there
will be plenty of auctions. You will still need a SMB to whatever pigtail
for the antenna connection though. I've seen someone sell a bundle of like
25 SMB to SMA cables, I don't know if anyone would want to buy them and
re-sell them in smaller quantities.
These are neat little receivers to play with even if you don't have a
TS2100. The header uses 2mm pins, which you can order all that from Mouser
(or whatever place is your preference). The Trimble software is available on
their FTP site, and the PDF manual is on their website.
I have one receiver with SMB to BNC pigtail I'm willing to sell (cheap) to
anyone interested. I also have one spare pigtail (I originally had 4
receivers and 5 cables) if anyone is interested in just that.
Jason
Could physical damage to the crystal account for this deviation?
-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On Behalf
Of Rick Karlquist
Sent: Saturday, January 20, 2007 11:51 AM
To: Discussion of precise time and frequency measurement
Cc: time-nuts@febo.com
Subject: Re: [time-nuts] 10811 warmup
On this unit, I suspect the oven was not at the correct operating
temperature. Thus, although it warmed up to some extent, it may
not have reached 80 degrees C. The real diagnostic would be to
slide it out of the case and look at the voltages on the thermistor
circuitry. However a crude check can be made by measuring the
oven current and comparing it to a good 10811. If it is substantially
lower, that would be a red flag. The fact that the frequency seems
to be fairly stable is no guarantee that you couldn't have the
wrong oven temperature. I have never heard of a 10811 with a properly
working oven that was that far off frequency. You need to realize
that crystals had to pass a frequency test before the lid was installed
on the crystal package. This was all done under automation. Thus it is
"impossible" for a crystal 100 Hz low to ever exist. And AFAIK, we
never made one on purpose.
Rick Karlquist N6RK
Mark Amos wrote:
Didier,
My experience with 4 10811's with widely separated serial numbers is
consistent with your
numbers below. Between 6 and 8 minutes of warm up from ambient (18C) and
they're stable at the
target frequency as measured with a recently calibrated 5328A (one without
a 10811 - since
remediated!)
The recent bad unit I bought on ebay behaved similarly - it warmed up and
within 10 minutes it
had stabilized around 9,999,915.
It is adjustable between about 9,999,900 and 9,999,920 or so using the
adjustment capacitor
through the hole in the case. EFC seems to function correctly as well
with a little over 1Hz
of adjustability with +-5 V.
As has been suggested, it must be some kind of test unit (or perhaps one
that failed QA?)
I replaced it with one from AST Global - they had a great return policy,
shipped fast and
packed well.
In any case, I've retired the bad one as a marker generator at 9.9999 MHz.
Mark
Message: 1
Date: Fri, 19 Jan 2007 22:53:28 -0600
From: Didier Juges didier@cox.net
Subject: Re: [time-nuts] Bad batch of HP10811's
To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Message-ID: 45B1A048.9090207@cox.net
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Warmup data on the HP 10811:
Here is some data collected on the internal HP 10811 timebase in my HP
5370A counter, which had been turned off and plugged off for about 3 days.
21:39:25, 9999798.6
21:39:35, 9999806.0
21:39:46, 9999822.6
21:39:55, 9999836.8
21:40:06, 9999853.2
21:40:15, 9999866.8
21:40:26, 9999881.7
21:40:35, 9999892.4
21:40:46, 9999904.1
21:40:56, 9999913.1
21:40:58, 9999915.2
21:41:07, 9999923.0
21:41:16, 9999930.1
21:41:25, 9999936.5
21:41:36, 9999944.0
21:41:46, 9999949.3
21:41:55, 9999954.3
21:42:06, 9999959.9
21:42:15, 9999964.0
21:42:26, 9999968.6
21:42:35, 9999971.8
21:42:45, 9999975.2
21:42:54, 9999977.9
21:43:05, 9999981.0
21:43:17, 9999983.9
21:43:26, 9999985.9
21:43:35, 9999987.8
21:43:46, 9999990.0
21:43:55, 9999991.3
21:44:07, 9999992.9
21:44:16, 9999994.0
21:44:25, 9999994.9
21:44:36, 9999996.1
21:44:45, 9999996.9
21:44:56, 9999997.7
21:45:06, 9999998.3
21:45:15, 9999998.9
21:45:17, 9999999.0
21:45:19, 9999999.1
21:45:21, 9999999.2
21:45:24, 9999999.3
21:45:26, 9999999.4
21:45:36, 9999999.7
21:45:45, 9999999.8
21:45:56, 9999999.9
21:46:05, 9999999.9
21:46:08, 9999999.9
21:46:10, 10000000.0
After that, the display was a stable 10,000,000.0 for the next 15
minutes (one reading was 10,000,000.1), then I stopped the data
collection.
The counter used was the HP 5334B with the Thunderbolt as external
reference.
Ambient temperature: about 22 degrees C (cool)
Bottom line: about 200 Hz from a cold start and about 7 minutes to
within 0.1 Hz of final frequency.
Didier KO4BB
time-nuts mailing list
time-nuts@febo.com
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
time-nuts mailing list
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Jack Hudler wrote:
Could physical damage to the crystal account for this deviation?
Pretty unlikely. If you drop a crystal, it will just break and
not work. The only way it could go down 100 Hz is by mass loading.
I don't know how this could happen in a sealed unit.
Rick Karlquist N6RK
Okay, I finally got around to building a little interface for my HP 10811's
this afternoon. I'm using a 24V supply for the oven. I built the oven
monitor LED circuit like in the manual so I know when it is warmed up so I
don't have to always probe the pin. Finally I'm using a linear regulator to
drop the 24V down to 12V for the oscillator supply.
Anyhow... The 10811-60155 that I got from 'her' I tried out first. No 10 MHz
output at all, not from initial power up or after it warmed up... The oven
did warm up after a few minutes, so that part seems good. Any thoughts? I'm
about to open it up and see if there are any loose or disconnected wires.
Second one is a 10811-60105 that I got for $25, the signal (10 MHz) came on
right after power up. After letting it warm up for about 20min (while I was
going through all the new posts on the list) I was able to coarse adjust the
frequency to match my GPSDO, it took a few turns but I don't know how long
ago this was used last. So I'm happy with this one.
Jason
I was looking at the pictures on the realhamradio website, and while he has
the B version the insides seem pretty similar.
Once you take off the top plate there is a thin piece of loose insulation,
when you remove that there is the main assembly inside. Does this assembly
simply 'pull' out or do I have to do something special? What is that big fat
gold pin sticking out in a corner for? Is there a signal or something on
that pin or is it to help pull the assembly out of the insulation?
Jason
Jason Rabel wrote:
I was looking at the pictures on the realhamradio website, and while he
has
the B version the insides seem pretty similar.
Once you take off the top plate there is a thin piece of loose insulation,
when you remove that there is the main assembly inside. Does this assembly
simply 'pull' out or do I have to do something special? What is that big
fat
gold pin sticking out in a corner for? Is there a signal or something on
that pin or is it to help pull the assembly out of the insulation?
Jason
Yes, it is simply held in by friction. Instead of pulling on the
test point, you might push on the assy through the adjustment hole.
Rick Karlquist N6RK