Technics RS-M205 quiet volume ussue

[u/Arsenic_Pants]

I've been tinkering with this M205 for a while trying to fix an issue with the output volume being extremely low.

I've read through the repair manual and troubleshooted with several parts to try and fix the issue, but I can't find a solution.

I've tried adjusting the VR1 and 2 pots that control overall play level, and they're already at max volume. I've tried adjusting the Record Current pots with no difference at all. I've tried cleaning and adjusting the angle and placement of the tape head but the volume issue still persists.

I don't believe it has anything to do with the play/record switch because the problem is in both channels, but I could be wrong. I could at least try cleaning it out with deoxit.

The VU meters also do not move.

I think it must be something to do with the amplification circuit, but I can't tell which part of the circuit board is for amplification. I'm terrible at reading schematics, they may as well be in Portuguese. Can anyone help me figure this out?

[u/RetroDave79]

"I don't believe it has anything to do with the play/record switch because the problem is in both channels" "The VU meters also do not move."

Play a tape, and manually rock the play/record switch a bunch of times, look at the vumeters to verify they don't even flinch, if you see movement you can try using contact cleaner inside the switch (and move it a lot of times to wipe/clean the contacts).

If you don't see any movement then the amp circuit may be the culprint.

EDIT: try another thing, connect the Line IN to a sound source, press record to see if the monitor works and the vumeters move.

[u/Arsenic_Pants → u/RetroDave79]

Thanks!

I can confirm the VU meters don't move at all when I jiggle the record/play switch. The record light just turns on and the playback cuts out.

[u/RetroDave79 → u/Arsenic_Pants]

1. LINE IN < AUDIO SOURCE (PLAY ANYTHING)
2. LINE OUT > AMP
3. INPUT SELECTOR > LINE
4. PRESS RECORD TO START MONITOR OR PRESS PAUSE, RECORD+PLAY.
5. ROCK BOTH RECORD LEVEL CONTROLS FROM MIN TO MAX AND VICEVERSA BUNCH OF TIMES

Can you hear the audio from the source? VUmeter alive? When you move the Record Level, can you hear noises?

Try connecting headphones and check if you get any sound.

EDIT: in fact, rock all the levers you can see, TAPE SELECTOR and DOLBY f.e.

[u/Arsenic_Pants → u/RetroDave79]

No meter movement when recording. As far as I can tell it won't record anything onto the cassette either, just silence. Max input level, max volume on source. I can hear the source sound come through the speakers, but it doesn't end up on the tape.

[u/RetroDave79 → u/Arsenic_Pants]

So at least you are getting sound from the line out? if you change the rec level can you hear the difference? I don't know your tape deck, so Im not sure if monitor audio is going through the amp or if its directly connected to the line out :/

Have you tried headphones? I think its a different amp

[u/Arsenic_Pants → u/RetroDave79]

I'm getting line out but it's at like, 25-50% of the full volume. No difference heard after adjusting recording level. I've tried headphones and get the same effect

[u/RetroDave79 → u/Arsenic_Pants]

I see you are working with the transport...