Hello Everyone!!!!
For my first thread on the EEVBlog Forums, I request your assistance!
Yesterday i managed to pick up a Fluke 8000A multimeter, an General Radio 1340 Pulse Generator, and a Power Designs Inc. 5015T Variable power supply, for a total of 20USD.
The Fluke 8000A and the GenRad 1340 both work beautifully, however the power supply does not. after rigging up a fuse (the fuse holder is broken) it will only output a maximum of about 5.8VDC when its stated voltage range is 0-50VDC at 0-1.5A.
So i found the manual online and have started testing voltages starting from the line voltage switch and lamp (old style 115VAC lamp) and working my way in.
The first issue i have encountered is a transistor marked Q9 on the schematic (
http://www.ko4bb.com/Manuals/09)_Misc_Test_Equipment/Power_Designs/Power_Designs_5015T_Power_Supply_Service_Manual.pdf). The transistor is a 2N4888 PNP can type. The manual says that it should have 0.6V between the base and the emitter which i have measured as 0.66V, and 0.9V between the emitter and collector which I measured as 0.03V.
I plan to continue my tests on the unit and update this post when I find a problem. If there is anyone who knows an equivalent to the problem components I would be eternally grateful!!
And now, for those of you who love old tech, pictures!! (pardon the imgur, the files were too big)
http://imgur.com/a/r0rLmProblem Parts:
Q9 - PNP - 2N4888
Q3 - PNP - TI1028A