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Re: E5052A Power On Test (3.3V Bus Supply)
Thank you Jeremy, I might pick one up to play with. I have spoken to Jeremy Everard last year about shared low phase oscillators development and ended up sending him the actives I was using that
By Leo Bodnar · #150665 ·
Re: HP 3403C True RMS Voltmeter display fault
When the orange “tombstone” plastic encapsulated surface mount tantalum caps fail, they fail shorted. Last year, while powering up a 9000/715, I saw one actually flame because I had the good
By Ed Marciniak · #150664 ·
Re: HP8510C TRL Calibration
Once calibration/correction constants have been computed externally on a computer, would it be possible to upload the computed correction constants to the 8510C so it can do calibrated measurements
By tom_iphi · #150663 ·
Re: 48-440 Hz AC power compatibility option (HP 8660B OPT 003) - acoustic noise (hum/buzz) from the unit?
My AC mains 60 Hz (however, good question!) Other than irritating (and not really all that bad, seeing as the cooling fan is about the same total dBa), it was more of a concern that it might be
By David Feldman · #150662 ·
Re: 48-440 Hz AC power compatibility option (HP 8660B OPT 003) - acoustic noise (hum/buzz) from the unit?
Do you mean that the audible noise is there when operating on 400 Hz, or that it's there at 50 or 60 Hz now? You are right to suspect the core laminations buzzing. On transformers intentionally built
By ed breya · #150661 ·
48-440 Hz AC power compatibility option (HP 8660B OPT 003) - acoustic noise (hum/buzz) from the unit?
My HP 8660B (subject of the instability issue now resolved) includes option 003 which is compatibility with 48-440 Hz power sources. The HP 8660B has a linear power supply (ca. 1970s, predates
By David Feldman · #150660 ·
Re: 8656B HPIB connector
Save money and defer the repair until such time as you have a need to use GPIB. The connectors are reasonably easy to find around here but very costly to ship. Peter KB2VTL
By Peter Gottlieb · #150659 ·
Re: 8656B HPIB connector
Hi thanks for the reply, I think part of the connector may be missing, I have moved house a few times , with the back panel hanging of the unit? from when I was investigating the power socket issue.
By Wayne Eckert · #150658 ·
Re: 8656B HPIB connector
You know, if it's not broken too badly, you can reattach the IDC into the ribbon cable manually by slowly and carefully jamming the leads against the forks in the connector. Put the connector in a
By ed breya · #150657 ·
8656B HPIB connector
Hi all, working on my 8656B sig gen, and managed to break the IDC Centronics connector , so the cable is no longer attached. Is there a suitable replacement available taht is not too ex[ensive. Have
By Wayne Eckert · #150656 ·
Re: HP 54512B (pair) repair
Jim - a lot of Elmers out there, it turns out... Radu [email protected]> wrote:
By Radu Bogdan Dicher · #150655 ·
Re: HP 54512B (pair) repair
Nope, Radu, a cable tie would require labor to install (“costs too much” in suit-speak). Cheaper to glue it down. I had a mechanical engineer coworker years ago with the nickname Elmer because
By Jim Ford · #150654 ·
Re: E5052A Power On Test (3.3V Bus Supply)
Unlikely to have been from a switching reg -- 1kHz is pretty low. Close-in spurs are often suppressed by some form of cancellation, and a little drift can cause the reappearance of spurs at around
By Tom Lee · #150653 ·
Re: HP 3403C True RMS Voltmeter display fault
Yes, Ed, I know exactly what you mean regarding the orange leadless tantalum caps. Sprague used to make them, and they told us that the orange material prevented them from printing the value,
By Jim Ford · #150652 ·
Re: E5052A Power On Test (3.3V Bus Supply)
70 MHz Surface Acoustic Wave (SAW) BPFs used to be common for satcom. 10 kHz is very narrow, though. I’m snickering a bit at the differences in spur performance in sig gens because I’ve seen
By Jim Ford · #150651 ·
Re: HP 54512B (pair) repair
Hi Radu, If you have a hot air desoldering station try to see if the heat will soften the glue/resin. Use low temp first and increase it slowly. Monitor the heat on the arm with an infrared
By Razvan Popescu · #150650 ·
Re: HP 54512B (pair) repair
Thank you, Mike. In terms of removing the arm from the switch stub (see pics enclosed a few messages down), where HP decided to use this brown resin to glue them together (completely unnecessary, in
By Radu Bogdan Dicher · #150649 ·
Re: HP8510C TRL Calibration
I put an 8510C driver into scikit-rf the other year that speaks the binary format and knows how to stitch sweeps, so if not it should be a quick code change especially if you already have PyVISA and
By jjoonathan · #150648 ·
Re: E5052A Power On Test (3.3V Bus Supply)
Hi Jim, thanks. I obtained the cal certificate for the other E5052A today. It was calibrated less than a year ago and this one shows an even lower noise floor.? It's a slightly newer unit and it has
By jmr · #150647 ·
Re: HP 3403C True RMS Voltmeter display fault
Hi AArnaud, Congratulations for the successful repair, and for having saved another valuable HP instrument from the scrap heap ! My conclusion is somewhat identical to my initial thoughts : start by
By Joel Setton · #150646 ·