TRIDENT

Hi, I?ve got this old Trident +/- 20VDC PSU ( Keith, you were right ?the pass transistors caused the fault! ) and I want to reduce the voltage to +/- 18,5 VDC . There are two 500k trim potis on the PCB, but I only get +19,6VDC and ? 18,2VDC if I turn them down. Can I just change the resistors or the potis to get my +/- 18,5VDC ? Sorry,I don't know how to upload any schematics... Thanks ? k.

Hi Keeno,

Here are the schemaic again (it disappear with the old forum)

First you must be sure that the regulation are ok, if you can adjust the +/- outputs aprox. 5 volts, the psu are ok.

To fix more width in voltage adjust/preset resistor RV2 and RV3, you can try to change this from the orginal value on 500 ohm to 1 kohm, or if you still will have this small adjust width and only move the voltage a bit up or down, you can play with the relations between R11/R12 and R20/R21.



--Bo

Thanks, Bo...k.