My Test Gear

Not sure if anyone would even care…leave a comment if you are interested in more detail – if enough people care I will do something better.

Make Model Description
Agilent 6612B Single output programmable DC bench power supply
Agilent 6612C Single output programmable DC bench power supply
Agilent U1732C A hand held LCR meter, a must have bit of gear when working with inductors
Agilent E3631A I have two of these, Tripple output programmable DC bench power supply, they are the best and most versatile general purpose bench supply I have, they are my go-to PSU, and I use them all the time.

Agilent E3634A Single output 0-50v 200W high power programmable DC bench power supply, when a couple of amps is not enough.

Agilent E3646A Dual output high power programmable DC bench power supply

Agilent E3640A Single output programmable DC bench power supply – brand new and boxed, don’t really have a need for it right now
Agilent MSO-X-3024A Mixed signal 4 analog, 16 digital 200Mhz Digital Oscilloscope with UART/RS232, I2C and SPI Serial Decode, Wavegen, DVM options installed.
Fluke 87V I have two of these and I use them all the time
Fluke 289 I have two of these and I use them fairly frequently
Hewlett Packard 34401A This is a mains powered bench meter, I use this most often for accuracy, its my reference meter and I tend have it hooked up to a computer to collect data from things I have under test
Hewlett Packard 33120A Function/Arbitrary Waveform Generator
Hewlett Packard 53131A 225Mhz Frequency Counter.

Hewlett Packard 339A Distortion Measurement/Analyser, really ace for spec’ing out audio circuits distortion characteristics
Keithley 2015 THD Bench Multi Meter with Distortion Analyser, really fast and accurate meter, I think I prefer this to the HP 34401A

Keithley 2110 5.5 Digit Bench Multi Meter

Maynuo M9711 Programmable 150W DC Electronic Load

Racal Dana 1999 2.6Ghz Frequency Counter, old 80’s gear but very good piece of kit

Tektronix 2445A 150Mhz 4 Channel Oscilloscope, sometimes the digital scopes just don’t cut it

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  1. Gerry,

    Bap8guy ?? , if yes i ended up at the good person i was searching.

    I saw you have done several fluke 1900a ‘s ………………well ,

    Mine died already some years ago and i would ask you if you could give me some advice to start its repair.
    Right now it is having a filckering display , and the chk will fail ( so no 10.000 )

    can you assist ??


  2. Have you managed to get the serial port working on your 6612C? I can’t get it to talk to my PC. There’s an option called ‘REMOTE FP’ [ENAB | DIS] which I can’t find any reference to in the man ual, not sure if that’s required or not. When I try to change it to ‘ENAB’, I get ‘RS232 IN USE’, not sure what that means…

  3. Hi Gerry, do you still sell the OCXO PCB’s / complete kit for HP/Agilent 53131A?.
    Great information!

  4. Hi Gerrry, Hope all is amazing.
    I saw your Rubidium 10M distribution amp video and it was very informative.
    I recently purchased an audio master clock and it has Atomic clock Input so I wanted to feed the clock with Rubudium 10mhz amp. It’s hard to find a pre made one online and I’m not too savvy with pcb’s and soldering. I wanted to ask if you do custom builds and if you do, how much would it cost to build a Rubidium 10mhz amp with 1 or 2 BNC outputs? Thank you

  5. Hi,

    Interested in your HP31131a Rev 1G Fully Built Trimble OCXO

    Do you have one??

    Any chance you could cal to your Rubidium time-base before shipping, which I’m not lucky enough to own LOL?



    1. Hi Paul,
      I do have them available, you can use the PayPal buttons on the blog page. I always soak test them before shipping, and I ensure they cal and are within a sensible calibration range. The calibration though is stored in the counter its self, and not on the OCXO so unless you sent me your counter, I cannot calibrate it against my reference.


  6. Hi Gerry, any suggestions for an HP 53131A that fails the self test with a FAIL-MEAS error? PS voltages all check ok. Cheers.

    1. I believe that error relates to measuring the frequency. If the input LED does not flash when there is a signal, its a problem with the front end, if the LED flashes, then it could be the front end or the counter logic (which is a custom chip). I would put a 100khz input signal into the counter, use the schematics and a scope and see where the signal makes it. If it gets to the input pins on the digital side then its the chip. I have never seen one fail myself but I have heard of one failing before. With a bit of luck its something more fixable.

  7. Hi Gerry, just curious if you think a flash read/write self-test fail is something fixable. I have a U8002a which has this failure, but not sure if I can somehow disable self-test or other option. I don’t think I can simply replace the chip as it probably has some proprietary software on it which I would not have…Thanks for any suggestions.

    1. I am not familiar with that PSU, at a guess I would say it might be “bricked”, perhaps from a previous failed attempt to flash the firmware. I would find out how to flash the firmware with the keysight tool for the same, and see if that recovers it. Otherwise, it will get complicated. The Flash is likely part of the micro-controller, and you are right you can proabbly not change that as it will likely have a custom bootloader on it. Have a look for Keysight forums, perhaps someone can point you in the right direction


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