2385 reconnect PS00 to P400 pin question

[dankik]

but sound comes out in waves

Are you saying that the volume goes high and low, or that it sound comes on then off?
See if you can isolate that problem to the Main Amp or Preamp. If it is only in one channel then use jumpers to connect Preout L to Main In R, and Preout R to Main In L and see if the problem changes sides.

 

[sendust]

Are you saying that the volume goes high and low, or that it sound comes on then off?
See if you can isolate that problem to the Main Amp or Preamp. If it is only in one channel then use jumpers to connect Preout L to Main In R, and Preout R to Main In L and see if the problem changes sides.

The volume on the left pulsates from clear to distorted back and forth at a quick pace, Used jumpers Pre out L to Main in R Pre out R to Main in L problem with sound changed sides .

 

[dankik]

Does it do that if you put your input into the Tape In jack and push the Tape button? That should bypass some of the front end boards.
Maybe it's time to get the scope out again and look at signal levels like when we were troubleshooting the bad channel.

 

[sendust]

Does it do that if you put your input into the Tape In jack and push the Tape button? That should bypass some of the front end boards.
Maybe it's time to get the scope out again and look at signal levels like when we were troubleshooting the bad channel.

I used the bose wave radio in tape 1 and 2 same issue with sound on the left, just more scratchier. Also noticed Left channel has a hum that is not present in right

 

[dankik]

That should work fine. Start with a lower input level and turn up, just so you don't over drive it.
What signal source were you listening to when you had the sound pulsing?

 

[sendust]

That should work fine. Start with a lower input level and turn up, just so you don't over drive it.
What signal source were you listening to when you had the sound pulsing?

I was listening to phono 1 and 2.. As i mentioned in my last reply, i did use the Bose on the Tape 1 input and found no change with left channel issue, with volume up a bit i heard a hum sounding like ground hum,

 

[dankik]

I would use your scope and look at the L & R inputs to the PE00 board on JE04 pins 1 & 3 to see if you can see the difference in the sine waveform in the Left channel compared to the good right channel.

 

[sendust]

I would use your scope and look at the L & R inputs to the PE00 board on JE04 pins 1 & 3 to see if you can see the difference in the sine waveform in the Left channel compared to the good right channel.

Will do tomorrow, , does it mater what source i test with, thinking phono

 

[dankik]

You want a signal that you can recognize on the scope so you know when it is distorted. The phono input has too much gain for a signal generator + it has RIAA phono equalization so you won't get a flat signal. Plus, with phono input you are going through the phono preamp. Tape in is the most direct path to the Pre/Tone Amp board.

 

[sendust]

You want a signal that you can recognize on the scope so you know when it is distorted. The phono input has too much gain for a signal generator + it has RIAA phono equalization so you won't get a flat signal. Plus, with phono input you are going through the phono preamp. Tape in is the most direct path to the Pre/Tone Amp board.

Ok signal it will be....thanks for the info.

 

[sendust]

I would use your scope and look at the L & R inputs to the PE00 board on JE04 pins 1 & 3 to see if you can see the difference in the sine waveform in the Left channel compared to the good right channel.

JE04 and J414 both pin 3 and pin 1 look the same, i held it for a while . where do i go next ?

 

[dankik]

Check JE02 Pins 1 & 3 and JE07 pins 1 & 3. Rotate Volume control and look at L & R signals to see if they are different or distorted.

 

[sendust]

Check JE02 Pins 1 & 3 and JE07 pins 1 & 3. Rotate Volume control and look at L & R signals to see if they are different or distorted.

JE02 and JE07 pin 1 and 3 , both signals look the same, also change the same when increasing volume.

 

[dankik]

The output signals at JE02 pins 1 & 3 then go directly to the Preout L & R RCA jacks on the back of the receiver. If they look good at JE02 the should be good at Preout.

• Try to connect your scope up to the L & R Preout jacks and see if the signals still look the same.
• If they both look the same, then there is a different problem.
• What input RCAs are you inputting the signal generator into?
• If it is the Tape In and all is good, next try the AUX inputs and see if it sounds the same. The AUX input goes through the selector switch and the Tape In does not.

 

[sendust]

The output signals at JE02 pins 1 & 3 then go directly to the Preout L & R RCA jacks on the back of the receiver. If they look good at JE02 the should be good at Preout.

• Try to connect your scope up to the L & R Preout jacks and see if the signals still look the same.
• If they both look the same, then there is a different problem.
• What input RCAs are you inputting the signal generator into?
• If it is the Tape In and all is good, next try the AUX inputs and see if it sounds the same. The AUX input goes through the selector switch and the Tape In does not.

Scope on L and R preout, perfect wave each side, I was using tape 1 for signal in. tried Aux found same perfect wave, also im not sure why but signal generator tone is the same sound on both channels. Just music is not, that may be normal. I must be doing something wrong, not sure how all areas tested, signal looks the same but doesnt sound the same when playing music.

 

[sendust]

The shielded wire that goes from the balance control to the JE04 had been handled alot and sometime causes issues, can i just replace that with 3, 24 gauge solid core wires ?

 

[dankik]

The shielded wire from the balance control to JE04 is an input to the PE00. If the signals looked OK and the same going into JE04 then the cable is OK.
What do the L & R signals look like at the PreOut RCA jacks? Does the L & R look the same?

Just music is not, that may be normal. I must be doing something wrong

What input are you listening to with music, Phono, AM, FM? If using the Phono input, what do you have plugged into the Phono RCA jacks?

 

[sendust]

The shielded wire from the balance control to JE04 is an input to the PE00. If the signals looked OK and the same going into JE04 then the cable is OK.
What do the L & R signals look like at the PreOut RCA jacks? Does the L & R look the same?

What input are you listening to with music, Phono, AM, FM? If using the Phono input, what do you have plugged into the Phono RCA jacks?

First the signal looks ok on the wire going to JE04 and the PE00 but sometimes it looses volume untill it is touched , I checked both ends they have perfect connection, moving the wire near the center causes a change, makes me think it has an issue , I also have shielded strand wire if that could work maybe. The signal L and R at the preouts look strong and the same. Im listening to music using a turntable , RCA jacks going to Phono 1, also using wave radio , RCA jacks into AUX

 

[dankik]

That wire should work fine.
So do you still hear the distortion in one channel, or is it OK now?
Is your Phono cartridge a MM type?

 

[sendust]

That wire should work fine.
So do you still hear the distortion in one channel, or is it OK now?
Is your Phono cartridge a MM type?

I dont think its the wire anymore , i think the PS00 board moves because its not secured in place and affects the contact.
The distortion is still there and its not only with phono, also when using radio into Aux. They both sound distorted on left channel, very clean on right