A quite simple old japanese compressor by Univox. For part substitutions (since stock parts is long gone obsolete...) the transistor were a low gain NPN silicon so PN2222 or 2N3903 should work. MD234 were silicon signal diodes so 1N4148s is a near enough sub. The spec of the original vactrol remains unknown so socketing a LED/LDR combo seems to be a wise decision.
Schematic, gutshots and info at FSB.
Now I was gonna build the red wolf but this looks nice - you are spoiling us my friend!!
ReplyDeleteThank you for the layout!
ReplyDeleteI had build one,using one of the others layouts online, but as simple as the circuit is, it didn't work. So I'm curious to know if anyone manages to make it work :)
(I remember I had found 2 schematics for it, but i can't remember which is the one I built...)
Did you manage to get this one working? My build doesn't work.
DeleteI worked on troubleshooting this build this weekend. I made a few changes and it works. Not saying it's perfect, but it works.
DeleteAdded cut at E 12 (Isolate the LED node)
LDR moves up to C 11 (to Q1 Collector)
Jumper moved up to H 6 (Connects to Pin 2)
1M resistor moved down to E 4 (Gives proper voltages)
Thank you, Samz!
DeleteWhich jumper did you move to H6 (pin2) : the first one (on column 1), or the third one (under the socket, on column 6, instead of the cut)?
ReplyDeleteThe top jumper in column 6. In this it runs D6 to I6, but it should be D6 to H6.
DeleteThe 3.3M coming from pin 6 needs to be connected to pin 2. I just lifted the jumper at I6, stuffed it through the cut at H6 and soldered it to the connection of the socket beneath.
DeleteOk, thank you Samz.
DeleteWhen you write "Not saying it's perfect, but it works", what do you mean? It doesn't sound good? It doesn't work as intended?
It works, but I don't know what the real circuit sounds like. So I'm not sure if it works the same or just good enough.
Delete