HP 6673A Power Supply - removing option J08

[Jay_Diddy_B]

Hi group,

In this thread:
https://www.eevblog.com/forum/testgear/hp-6671a-option-j05-j09-5v-250a-power-supply/msg713507/#msg713507

I did a repair on an HP6671A and removed the option J05.

This thread is about removing option J08 on an HP6673A.

The base model is 35V and 60A. If option J08 is installed the power supply becomes 40V and 50A.

I wanted to remove J08.

Summary

Change about 10 resistors on the A5 control board.

Reprogram the EEPROM on the front panel board. This can be done over the GPIB interface. I wrote a program based on the one provided in the service manual. I rewrote the program in VB.net and use the AR488 developed by forum member WaveyDipole.

Calibrate the power supply. An accurate voltmeter and an accurate shunt are required for the calibration.



I have attached a pdf file with the details.

Regards,
Jay_Diddy_B
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