QT LR2000 aka. Chroma 16502 Milliohm Meter

[sixtimesseven]

I picked up a LR2000 Milliohm Meter (aka. Chroma 16502) from Ebay and apart from the usual wear and the missing cal. it seems to be in good condition.

Below you find what I could come up with so far. I will save the firmware as soon as I get the required adapter and add it here. Firmware is v1.32.
If sombody happens to have a newer version I would be very interested to update since my unit is a pretty early model. Also, pictures of the Temperature Sensor Board would be of interest since I do not have the hardware option...

Pictures / Teardown:
https://www.flickr.com/photos/137236105@N05/

Datasheet & Manual:
https://www.dropbox.com/sh/tfv1xtd4gajtjcj/AAClgmVPqishVaijVZMTUQhPa?dl=0

However, strangely I cannot disable "LOCK" via keypad, only via rs232 (haven't tried GPIB yet). RS232 commands are (9800B 9N1 with carriage return) supposed to be identical to the manual above GPIB commands. And some things work like "*trg" but e.g. "system:local" is not one of them




UPDATE: Figured out the Calibration Password

The password for Chroma 16502 aka QuadTech2000 Milliohm meters is:
[ArrowUp, ArrowDown, ArrowLeft, ArrowRight, Trigger]

[sixtimesseven]

Figured out that it is likely that there were some changes between my firmware v1.32 and the manuals v2 firmware.
I could not get for example "system:local" work at all.

What works is to send the GPIB GTL command message.

Pyvisa example: lr2000_DisableRemote.py here:
https://www.dropbox.com/sh/tfv1xtd4gajtjcj/AAClgmVPqishVaijVZMTUQhPa?dl=0



What I am missing now is the Password to enter cal. data. Manual does not mention a default one so unless I find and some obvious ones do not work. Might have to look into the Firmware