Phase Linear 4000 Resurrection

[Geezer]

I may need some help in determining that from my meter? I put in a signal but there was no passthrough of signal... just a sine wave goes in but none comes out. IIRC, per the service manual there was a signal using the tape monitor, but no signal at all at the output of the preamp.

I will get to reflowing all of the ones on the main board soon I hope... and dig into the service manual. This thing is too cool to pass along for parts!

 

[WOPL Sniffer]

I may need some help in determining that from my meter? I put in a signal but there was no passthrough of signal... just a sine wave goes in but none comes out. IIRC, per the service manual there was a signal using the tape monitor, but no signal at all at the output of the preamp.

I will get to reflowing all of the ones on the main board soon I hope... and dig into the service manual. This thing is too cool to pass along for parts!

Well, you didn't say that you looked at the output with the scope or how you were actually troubleshooting with the book. or if you were just poking around without a plan (or with a chopstick). If you are not using the book to correctly troubleshoot a unit, it's a crapshoot and I'll defer to the guys with patience.

 

[laatsch55]

I may need some help in determining that from my meter? I put in a signal but there was no passthrough of signal... just a sine wave goes in but none comes out. IIRC, per the service manual there was a signal using the tape monitor, but no signal at all at the output of the preamp.

I will get to reflowing all of the ones on the main board soon I hope... and dig into the service manual. This thing is too cool to pass along for parts!

Too cool to pass along for parts yes.....but you're gonna get tired of working on it..........i'll bet on it....

 

[marcok]

-Remove all boards
-Insert tone board and logic board after cleaning their connectors .
-Correlator , peak unlimiter , ambience , equalizer , tone , tape monitor in out position .
-Use aux input and check again .
In this config it's only a 15 dB line amp .
Ciao
Marco

 

[WOPL Sniffer]

-Remove all boards
-Insert tone board and logic board after cleaning their connectors .
-Correlator , peak unlimiter , ambience , equalizer , tone , tape monitor in out position .
-Use aux input and check again .
In this config it's only a 15 dB line amp .
Ciao
Marco

Then when it works for 5 minutes and dies, rinse and repeat until you get pissed and send it to Davy Jones Locker.

 

[Geezer]

Thanks for your help WOPL Sniffer... have only been able to get a peek at this thing for a few minutes here and there so my approach has been scattered rather than anything close to methodical. I will come back after I've finished up my other project, SM in hand and get going on this thing.