What way around are these voltage regulators?

Mister 'tater Man . . . . . . .



With that low of a numerical coding assignment, I would suspect them being common transistors, likely a MMBT3904L in this case.

Initially use the lowest OHMs function to confirm that what seem to be direct up and down foil connections between the two units, are possibly being confirmed.

Thinking there of a paralleling of two units for greater power handling capacity OR their arrangement into a Darlington configuration for upping the pairs combined gain.

Next, check them out in common DIODE test mode with a DVM.

Bottom left terminal at the 1 side would be BASE
Top center terminal above the A would be COLLECTOR
Bottom right terminal would be EMITTER.

If this were a regulator, one would expect almost adjunct mounting of in and out electrolytic bypassing capacitors, as is associated with a 3 term regulator.


Thasssssit . . . . . .


BTW what type or piece of . . . . . E - Quip - Ment . . . . are we having ourselves here ?

Since I can’t see the total board.


73’s de Edd

 

Yep, shore did . . . . . . . YOU . . . . and heavy on the YOU, are more apt to encounter a BC 846-A on YOUR manufacturing side side of the big waters.
While I, me,we,us and Mr 'tater man . . . . are more likely to encounter a MMBT3904 being on OUR boards.

Didn't happen to see the "Code Book " referencing . . . . residing on my hard drives since the very early 2000's . . . . since I wuz bizzy, a poking up my entry, and then let er' rip . . . . just after doing so.

 

I just knew that on the side of the board shown, that I could see, I saw no transformer to get the required initial peak of 1000V upwards, to initially get a tube into striking and flashover and then a decline down to ~ 300-400 VAC for actual running.