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Morley Slimline Stereo Volume

Posted: 02 Sep 2014, 22:35
by idy
Picked this up at a yard sale. Could not find a schematic.
Inside the transistor has two legs broken from the pcb. It is labeled:
F78L (Maybe F7BL)
09AWC
8215

Any ideas what transistor it is?

The pedal uses an LED and LDR with a little light shield controlled by the pedal (like other Morleys)
It seems they had a platform that allowed them to build several pedals on the same pcbs. Thus the second board (labeled "WAHB") with what looks like an inductor on it. Strange the "inductor" has a bit of black tape covering a hole on the top. Uncovering this hole reveals that the black box is not empty...
morley ssv1.jpeg
morley ssv1.jpeg (45.15 KiB) Viewed 546 times
morley ssv2.jpg
morley ssv2.jpg (55 KiB) Viewed 546 times

Re: Morley Slimline Stereo Volume

Posted: 04 Sep 2014, 23:53
by idy
S0 I took the transistor out and it is definitely dead.
I think that thing in the round black box is a double vactrol; one led striking two ldrs. The input and output jacks are only attached to that board.
Funny thing is the transistor seems to be connected so one leg is connected directly to the supply voltage (the top of the board, heavy black wire), and another leg is tied directly to ground ( the middle leg, trace with two black jumpers and then one more black jumper to the ground on one of the jacks. The third leg provides power to the two less and, through the ldd, powers what I think is the dual vactrol.

Transistor should be EBC how?
morley ssv.jpeg

Re: Morley Slimline Stereo Volume

Posted: 05 Sep 2014, 04:35
by idy
What do you think that isn't a transistor but a voltage regulator?
F78L (Maybe F7BL)
09AWC
8215

That would make sense.

Re: Morley Slimline Stereo Volume

Posted: 05 Sep 2014, 17:13
by idy
It has been suggested at another forum that the mystery part is a 7809 regulator. Which pretty much has to be right.
I jumpered one of the batteries and the regulator and it works, or one channel works and the other is always on. Maybe this would make a nice optical wah shell....