[Test-Equipment] Tektronix PS 503A

[Brian Harris]

I just bought and received a Tektronix PS 503A power supply and have a few questions and needs.  


First, it appears to be operating....at least there are adjustable voltages available on the +/- 0-20V outputs.  The RED LED in the middle of the printed box that says 400mA max is always lit.  Is this correct?

Second, the overcurrent LEDs flash a little when I move the current limit pots.  I suspect this is normal and may be dirty pots.  I expect they should only be on constantly when there is an actual overcurrent situation.  


Third, the 5V output has voltage present when I press the button titled OUTPUT, which behaves like it's a momentary on switch rather than a toggle on/toggle off switch.  Is it supposed to be momentary action or is this switch defective? 


Fourth, it has two broken knobs.  One is the largest knob, which is the Volts Dual Tracking knob.  The other one is the larger of the concentric knobs that adjust the coarse voltage. Does anyone have a parts unit with these knobs?

Thank you,

 
Brian Harris, WA5UEK
cell 214-763-5977
email cosmophone at yahoo.com