PL700 series 2 working but some AC hum ?

[Greg]

Finally got to test it ! All original mostly inside so question is grounding the chassis properly a plus or
Minus in this case and what is most common prevalent cause of AC hum on PL700 Series 2 ?

 

[WOPL Sniffer]

Don't ground it. 40 year old shit is bound to make some noise. WOPL it and put the noise problems behind you.

It's a non polar plug so unplug it, turn the plug 180 degrees and check it out. It could be 100 things. Keep the LED and fluorescent lights away from it, try a different Preamp, cables, speaker wire and check the chassis for bee's.........................

 

[WOPL Sniffer]

could be leaky caps, did you put McDonalds straws over the transformer bolts?

 

[Greg]

Will check it out ! Great ideas ! On with the Show ! Thanks very much .

 

[MusicSteve]

is this the one you were just working on?

 

[Greg]

Yes Traced it back to a bad Interconnect between preamp and amp ..Like everything I do I find it once I stop looking lol.

 

[Greg]

I have been trying out this Carver still learning on it .

 

[grapplesaw]

I have been trying out this Carver still learning on it . View attachment 71300

These are great. What is the serial number of it. Ther two phono sections . First runs are like the Phase linear 4000 and the later like the Carver c-1
the Carver 4000t phono section adds a pair of long tail transistors on MM input

 

[Greg]

8859 C interesting > ?

 

[grapplesaw]

That’s a later one. You would be very happy with it.

 

[Greg]

Yes it seems to compliment the PL 700 series 2 well.