Please see the attached picture. I have rather badly "repaired" NS10 on the bench and one transistor is missing. It looks to be the pass element for the regulator, and I'd like to know what the original transistor was.
I have schematics, but they don't show the power supply.
I have schematics, but they don't show the power supply.
Attachments
If it's an NPN in a TO-220 package, D44H11 would be better than whatever they bought in 1978, in every specification. TIP-48 would be about the correct vintage, and would work well in a uA723 regulator. However I don't have a schematic either so I don't know what the >original< part number was.
Naturally you'd want to triple-check the pinout before ordering or soldering!
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Naturally you'd want to triple-check the pinout before ordering or soldering!
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Thanks Mark.
The original is missing (that was an internet picture, not mine), and that is what's throwing me a bit. If it was a typical capacitance multiplier type of power supply or with zeners on the base, it becomes pretty easy to figure out. However given the standard pin configuration of a TO220 power transistor, the collector would appear at the output with the emitter being the high voltage side. In other words, emitter and collector are reversed.
That's why I wanted to know what the original was. Just to confirm what I amp seeing.
The original is missing (that was an internet picture, not mine), and that is what's throwing me a bit. If it was a typical capacitance multiplier type of power supply or with zeners on the base, it becomes pretty easy to figure out. However given the standard pin configuration of a TO220 power transistor, the collector would appear at the output with the emitter being the high voltage side. In other words, emitter and collector are reversed.
That's why I wanted to know what the original was. Just to confirm what I amp seeing.
investigate is it N or P, then change with your favorite
if generic good part is inside, I see no reason to change it at all
ediT: we typed in same time
I'll see what I have of sch, but doubt I have PSU
can you trace sch and post?
if generic good part is inside, I see no reason to change it at all
ediT: we typed in same time
I'll see what I have of sch, but doubt I have PSU
can you trace sch and post?
Who knows, it might have been a TO-126. In that case it would be ECB rather than BCE, in other words, reversed.