EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: pwr19 on August 06, 2022, 03:17:41 pm
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Hello All,
I have an old Kenwood PWR18-1.8Q linear power supply that works but the reported voltages are inaccurate by as much as 0.8 V.
I just can't find any calibration procedures online.
I found some information here:
http://agilent34970a.blog.fc2.com/blog-entry-71.html?_x_tr_sch=http&_x_tr_sl&_x_tr_tl&_x_tr_hl (http://agilent34970a.blog.fc2.com/blog-entry-71.html?_x_tr_sch=http&_x_tr_sl&_x_tr_tl&_x_tr_hl)
Can anyone help with how to calibrate?
I did open the unit and found two pots. But the silk screen is not very clear.
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Yes, the schematic doesn't seem to be readily available online (for free).
What I would do is first record the position of the two pots, then turn them a little and see what the effect is. My guess is that they are not actually adjusting the voltage and current directly, but more likely are just responsible for the two meter readings.
In other words, hook up a load, an external voltmeter and an external ammeter, and see what happens when you turn the pots. If my guess is correct, only the power supply's meter readings will change.
Normally, one calibrates these things by adjusting the pots so that the meter readings agree with your external metering at the full rated voltage and the full rated current.