Re: 54615B Agilent Scope Amplitude Low When Measuring 120V AC
The other issue with measuring mains is spikes and transients. They cn easilly exceed the rating of? probe and 'scope. You may get? away with it for yers but it can kill an input. Murphy's law says it will happen when you use your best 'scope, not the old clunker.
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Re: 5065A rubidium frequency standard, no 2nd harmonic.
I restored a 5065A that had been tucked away a long time. Replacing the Rb cavity with a new one and it worked OK
but then started to loose the 2nd harmonic. Photo Current was OK. All other readings as well.
The fault was located in the 60 MHz RF pump assembly A3 feeding the SRD in the Rx part of the Rb cavity.
The transistors started to fail, one after the other and eventually, I decided to replace almost all of them.
There are at least two versions of the A3 assembly. Mine being most likely the first one using plastic cased
FETs for Q2,Q6, Q8 qnd Q5. I replaced the transistors according to below:
Q1 = 2N708, Q2, Q6, Q8, Q5 = 2N4416. Q3= 3N128 (was OK). The bipolar Q4 and Q7 was also OK (Q7 can be
replaced with a BC557 (!). The output transistor Q9 was replaced with a 2N5109 and also provided with a heat sink.
Capacitor C37? (100uF) was replaced as well.
After repair, it will be necessary to check the AGC functionality by recalibrating the unit. I also replaced R40
with a 10-turn type since the SRD was found to be quite sensitive for correct bias setting.
After this, I drilled addittional holes in the cover to be able to access some of the adjustments so that I would not
have to dissassemble the unit during calibration.
Best Regards
Ulf Kylenfall
SM6GXV
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Re: Placing Shelf on Casters for HP Equipment
I have 3 attached to the back of my bench.? No issues in the ~3 years I've had them.? BTW, I put masking tape labels on the plug ends of the power cords so I know what plug goes to what instrument.? ?HTH.? ? ? ? ?Jim Ford?
Sent from my Verizon, Samsung Galaxy smartphone
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-------- Original message -------- From: "Michael A. Terrell" <terrell.michael.a@...> Date: 11/19/21 6:45 AM (GMT-08:00) Subject: Re: [HP-Agilent-Keysight-equipment] Placing Shelf on Casters for HP Equipment
Have you seen these four foot, 12 outlet strips for $20? I have about a half dozen.? A couple failed when I lost the netral on my electric service, and the line voltage went up past 160 VAC on a 120VAC line. It fried the MOVs, and tripped a circuit breaker, which is how it was supposed to work. The other side of the line dropped to 60 VAC but my old Dell Optiplex 780 and Insignia video monitor kept working.
After I sent that message I found these Tripp Lite rails
(),
which seem to be exactly what I was looking for. Anyone have experience
with these, or with Tripp Lite in general?
Matt
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Re: Placing Shelf on Casters for HP Equipment
Have you seen these four foot, 12 outlet strips for $20? I have about a half dozen.? A couple failed when I lost the netral on my electric service, and the line voltage went up past 160 VAC on a 120VAC line. It fried the MOVs, and tripped a circuit breaker, which is how it was supposed to work. The other side of the line dropped to 60 VAC but my old Dell Optiplex 780 and Insignia video monitor kept working.
After I sent that message I found these Tripp Lite rails
(),
which seem to be exactly what I was looking for. Anyone have experience
with these, or with Tripp Lite in general?
Matt
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5065A rubidium frequency standard, no 2nd harmonic.
Hi all,
?
I have a 5065A Rubidium Standard that was working ok, but has lost the 2nd harmonic.
My voltages are all ok, the physics package hasn't overheated and I have replaced the usual resistors on the lamp assembly (and it was running fine afterward for a while), the lamp illuminates, and I've done the procedure to remove cell flooding.
All readings on the 'circuit check' switch are nominal, apart from the 2nd harmonic position. No matter what I do, I can no longer get it to raise above 0.
However, when I first turn the unit on, the needle drops to 0 and flicks a little before settling on 0 and staying there.
?
Can someone help me get this unit up and running again?
?
Thanks!
Jared
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Re: Placing Shelf on Casters for HP Equipment
Hi mat
Sorry you say . See the tripp lite ones I posted in my most recent message.
??
But did you take on board that the support rails that are fixed to the front
verticals should be mounted within the rack
Onto the rear of the vertical mounting holes in the method I described in my
earlier Email
Regards Paul
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-----Original Message----- From: [email protected][mailto: [email protected]] On Behalf Of Matt Huszagh Sent: 19 November 2021 01:05 To: Paul Bicknell <admin@...>; [email protected]Subject: Re: [HP-Agilent-Keysight-equipment] Placing Shelf on Casters for HP Equipment "Paul Bicknell" <admin@...> writes: Hi Mat
Have you considered
rails/
?_ga=2.54387112.1882785233.1637237241-481532309.1636398967 I did indeed. That was actually the second link I posted. They look good. I'd still prefer something that doesn't occupy the front mounting and covered a bit more of the depth of the instrument (which I'd like to keep flush with the front of the rack), but they would solve the "density" problem. Fortunately, I think I found something even better. See the tripp lite ones I posted in my most recent message. Matt
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Re: HP8648b corrupted firmware
I got the memory module, but the chips are soldered, so I need more time to make the adapter to module connector. I do not want to desolder OTP ROM, as I am not sure that they will survive.
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Re: 54615B Agilent Scope Amplitude Low When Measuring 120V AC
Completely neglecting any powerline considerations, most scopes
have a maximum vertical input voltage rating, typically a bit more
than the peak to peak input at the maximum volts/division.? This
does not consider the probe.
I'd feel reasonably happy measuring low frequency waveforms with
an X10 probe, 5 volts (50 volts/div scaled) at about 200 volts
plus.
Probes have a maximum voltage limit.
Scope inputs have a maximum voltage limit.
All of those go down as the frequency goes up.
That's on a 1 meg input impedance.
For a 50 ohm impedance, don't even think it.
Then again, I have a high voltage scope probe, too.
Harvey
On 11/18/2021 10:06 PM, Bostonman
wrote:
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This is all useful information about safety. I don't want to
deviate too much, but does seem the original question is somewhat
answered.
Ignoring the safety aspect of measuring 120V, is it safe for the
scope to be measuring 120V or should some soft of device be used
to reduce the voltage?
I have measured 10s of thousands of voltage using a high voltage
probe, but that was with a DMM.
As I stated, I need to do more research on the safety aspect. I've
never heard of anyone blowing up a scope or a probe, however, I
remember blowing a fuse at an old job.
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Re: 54615B Agilent Scope Amplitude Low When Measuring 120V AC
This is all useful information about safety. I don't want to deviate too much, but does seem the original question is somewhat answered.
Ignoring the safety aspect of measuring 120V, is it safe for the scope to be measuring 120V or should some soft of device be used to reduce the voltage?
I have measured 10s of thousands of voltage using a high voltage probe, but that was with a DMM.
As I stated, I need to do more research on the safety aspect. I've never heard of anyone blowing up a scope or a probe, however, I remember blowing a fuse at an old job.
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Re: Placing Shelf on Casters for HP Equipment
Yeah, I have seen their uninterruptible power supplies at various employers.? ISTR they worked better than most.? ? ? ? Jim Ford in Southern California?
Sent from my Verizon, Samsung Galaxy smartphone
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-------- Original message -------- From: Dave McGuire <mcguire@...> Date: 11/18/21 5:56 PM (GMT-08:00) Subject: Re: [HP-Agilent-Keysight-equipment] Placing Shelf on Casters for HP Equipment
On 11/18/21 8:01 PM, Matt Huszagh wrote: > After I sent that message I found these Tripp Lite rails > (https://www.tripplite.com/4-post-rack-mount-installation-kit-select-rack-mount-ups-systems-side-mount~4POSTRAILSM), > which seem to be exactly what I was looking for. Anyone have experience > with these, or with Tripp Lite in general? ?? Tripp Lite has been around since the 1920s, and have generally been a pretty decent company. ????????????? -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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Re: Placing Shelf on Casters for HP Equipment
On 11/18/21 8:01 PM, Matt Huszagh wrote: After I sent that message I found these Tripp Lite rails
(),
which seem to be exactly what I was looking for. Anyone have experience
with these, or with Tripp Lite in general? Tripp Lite has been around since the 1920s, and have generally been a pretty decent company. -Dave -- Dave McGuire, AK4HZ New Kensington, PA
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Re: Placing Shelf on Casters for HP Equipment
"Paul Bicknell" <admin@...> writes: Hi Mat
Have you considered
?_ga=2.54387112.1882785233.1637237241-481532309.1636398967 I did indeed. That was actually the second link I posted. They look good. I'd still prefer something that doesn't occupy the front mounting and covered a bit more of the depth of the instrument (which I'd like to keep flush with the front of the rack), but they would solve the "density" problem. Fortunately, I think I found something even better. See the tripp lite ones I posted in my most recent message. Matt
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Re: Placing Shelf on Casters for HP Equipment
After I sent that message I found these Tripp Lite rails
(),
which seem to be exactly what I was looking for. Anyone have experience
with these, or with Tripp Lite in general?
Matt
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new folder in the files just for Fiber optics
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More goodies on the Stuff page, plus sale on scopes and power supplies
Just in time for Christmas, we have put all kinds of goodies on the Stuff Season page, especially under the Surprises Category (including 20 pounds of DC Fans!), Scopes and Power supplies sections. Lots of HP logic analyzer accessories added, pods, clips and cables. Also interesting hp stuff in the "needs love" section.
You can see it all here:
BC (where we live) has had its share of disasters this year, fires, now rain and floods, but so far, we are sill operating, although shipping is slow. Drop by and have a look, maybe you will see something you like and help us clear out some more space!
Have a great thanskgiving,
all the best,
walter (walter2 -at- sphere.bc.ca)
sphere research corp.
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Re: HP 28687A Wire Tester - Trying to find manuals
Wavetek had really nice 100BaseT, Cat5e, Cat6 testers until that division got
gobbled up by Ideal (and of course they killed the product line).
Paul
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On Thu, Nov 18, 2021 at 02:39:07PM -0700, Bruce wrote: Fluke bead HP to the market with 100BASE-T and held the market for some time
Cheers!
Quoting "Greg Muir via groups.io" <big_sky_explorer@...>:
Herbert,
The 28687A became obsolete rather quickly primarily because it was
restricted to qualifying/testing only 10BASE-T wiring. Shortly after it s
manufacture things progressed quickly to 100BASE-T networks and few users
needed to digress to testing narrower bandwidth network wiring. My opinion
is that HP really didn¡¯t keep an eye on the network wiring arena and
produced a limited lifetime instrument.
I picked up the same unit several years ago for $75 new-in-box with all 12
of the remote loopback hoods plus the 28638 ribbon connector-to-RJ45
breakout adapter (port adapter) that attaches to the front panel
connector. It did come with the user manual with around 115 pages of
information and would be quite a chore to copy. If your unit came with the
front cover it should have the basic instructions posted inside it on a
label.
The operation manual is the only document that I have seen. So far there
has never been any information on service data and/or schematics for this
unit. A considerable number of possible error codes listed in the manual
that the unit could display if the self-test fails are all referenced to
¡°send to HP for repair.¡±
I looked at the loopback hoods. The enclosures are all glued together so
there is no access into them to see what they contain. The 28638 adapter
appears to be held together with screws so I might be able to provide a
connection list as to what contact is connected to another contact.
Given the test capability to only fully qualify 10BASE-T networks I
occasionally use it to only verify proper wiring polarity on existing and
new LAN installations where the cabling passes through numerous patch
panels and cross connects and there is a possibility of wiring errors. But
that is about all it is good for these days unless there is such a
condition where even a 10BASE-T network would be brought to its knees from
some gross wiring problem.
If you haven¡¯t fired it up it is quite unique running tests with all of
the numerous internal relays clicking as they move from one to another of
each of the 12 cable circuits as it sets up for each one.
Greg
!DSPAM:6196c806168331946120465!
--
Paul Amaranth, GCIH | Manchester MI, USA
Aurora Group of Michigan, LLC | Security, Systems & Software
paul@... | Unix/Linux - We don't do windows
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Re: HP8648b corrupted firmware
Just a thought but I bought 2 8664's with an error code. I left them plugged in for 24hrs and it recharged the internal battery. Then it checked out fine, no errors. Might try just plugging it in for a couple of days and see if it works?
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Re: HP 28687A Wire Tester - Trying to find manuals
Fluke bead HP to the market with 100BASE-T and held the market for some time
Cheers!
Quoting "Greg Muir via groups.io" <big_sky_explorer@...>:
toggle quoted message
Show quoted text
Herbert,
The 28687A became obsolete rather quickly primarily because it was restricted to qualifying/testing only 10BASE-T wiring. Shortly after it s manufacture things progressed quickly to 100BASE-T networks and few users needed to digress to testing narrower bandwidth network wiring. My opinion is that HP really didn¡¯t keep an eye on the network wiring arena and produced a limited lifetime instrument.
I picked up the same unit several years ago for $75 new-in-box with all 12 of the remote loopback hoods plus the 28638 ribbon connector-to-RJ45 breakout adapter (port adapter) that attaches to the front panel connector. It did come with the user manual with around 115 pages of information and would be quite a chore to copy. If your unit came with the front cover it should have the basic instructions posted inside it on a label.
The operation manual is the only document that I have seen. So far there has never been any information on service data and/or schematics for this unit. A considerable number of possible error codes listed in the manual that the unit could display if the self-test fails are all referenced to ¡°send to HP for repair.¡±
I looked at the loopback hoods. The enclosures are all glued together so there is no access into them to see what they contain. The 28638 adapter appears to be held together with screws so I might be able to provide a connection list as to what contact is connected to another contact.
Given the test capability to only fully qualify 10BASE-T networks I occasionally use it to only verify proper wiring polarity on existing and new LAN installations where the cabling passes through numerous patch panels and cross connects and there is a possibility of wiring errors. But that is about all it is good for these days unless there is such a condition where even a 10BASE-T network would be brought to its knees from some gross wiring problem.
If you haven¡¯t fired it up it is quite unique running tests with all of the numerous internal relays clicking as they move from one to another of each of the 12 cable circuits as it sets up for each one.
Greg
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Re: HP 28687A Wire Tester - Trying to find manuals
Herbert,
?
The 28687A became obsolete rather quickly primarily because it was restricted to qualifying/testing only 10BASE-T wiring.? Shortly after it s manufacture things progressed quickly to 100BASE-T networks and few users needed to digress to testing narrower bandwidth network wiring.? My opinion is that HP really didn¡¯t keep an eye on the network wiring arena and produced a limited lifetime instrument.
?
I picked up the same unit several years ago for $75 new-in-box with all 12 of the remote loopback hoods plus the 28638 ribbon connector-to-RJ45 breakout adapter (port adapter) that attaches to the front panel connector.? It did come with the user manual with around 115 pages of information and would be quite a chore to copy. If your unit came with the front cover it should have the basic instructions posted inside it on a label.
?
The operation manual is the only document that I have seen.? So far there has never been any information on service data and/or schematics for this unit.? A considerable number of possible error codes listed in the manual that the unit could display if the self-test fails are all referenced to ¡°send to HP for repair.¡±
?
I looked at the loopback hoods.? The enclosures are all glued together so there is no access into them to see what they contain.? The 28638 adapter appears to be held together with screws so I might be able to provide a connection list as to what contact is connected to another contact.
?
Given the test capability to only fully qualify 10BASE-T networks I occasionally use it to only verify proper wiring polarity on existing and new LAN installations where the cabling passes through numerous patch panels and cross connects and there is a possibility of wiring errors.? But that is about all it is good for these days unless there is such a condition where even a 10BASE-T network would be brought to its knees from some gross wiring problem.
?
If you haven¡¯t fired it up it is quite unique running tests with all of the numerous internal relays clicking as they move from one to another of each of the 12 cable circuits as it sets up for each one.
?
Greg
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Re: Query about 40 GHz sig gens
Hi all ? Interested to see you talking about? the HP 70000 equipment and the Z40 option and that their dues not seem to be any documentation for it ? We are indeed still missing a number of documents for the 70 K equipment could either of you just clear up a point Am I correct that the spectrum analyser system for 40 Ghz was the 71209 that comprised of a 70910 analyser with an extra socket on the back that connected to the Z40 module that was basically a down converter with a 2.4 MM connecter ? ? The only reference I can find is in the MMS Catalogue Pages 62-64 & Pages 157 - 158 ? You also talk about ?? Can you elaborate more on the Z40 Option of the HP 70340a ? did this ever exist ?? ? Best Regards Paul ? ?
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From: [email protected] [mailto:[email protected]] On Behalf Of green
Sent: 18 November 2021 16:36
To: [email protected]
Subject: Re: [HP-Agilent-Keysight-equipment] Query about 40 GHz sig gens ? hi? jfphp,
Can you elaborate more on the Z40 Option of the HP 70340a ?
I have the non-Z40 version, and would like to know what the upgrade entails ?
-- Any .pdf Docs or photos? on the Z40 details ?
thank you,
rick
(I have the Z40 option for the SA, that does nicely go up to 40GHz, but no docs on that Option either)
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Michael A. Terrell
Jared Cabot
Paul Bicknell
Dave McGuire