phase linear 400

Sunnbobb said:
One further consideration. The previous owner wired in a couple of input potentiometers ala Series 2. I didn't mention them as I assumed the Amp was working prior to losing some transistors. Here are some pictures, I somewhat wonder if the input/output wiring is incorrect? I would remove them, however there are two holes in the faceplate for them. I did go ahead and put them back in the faceplate just to see if there was some sort of grounding needed, but the issue of the dbt still exists.
Click to expand...
Original 400 S2 pot and wiring.
The middle lug (red wire) is known as the "wiper", and ALWAYS carries signal to the control board.
The black wire carries signal from the RCA to the pot.
The sliver wire is the ground or shield wire. Goes from the RCA copper plate to that pot lug, then from the pot lug to the control board.
You can use a twisted pair, mini coax such as Belden RG316, or the original Belden cable that PL used as shown in the photo.
Many of us building or having built WOPLs bypass the signal attenuators (front pots) or leave them out all together.
My three S2 WOPLs have LEDs in place of the attenuators.
 

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George S. said:
Original 400 S2 pot and wiring.
The middle lug (red wire) is known as the "wiper", and ALWAYS carries signal to the control board.
The black wire carries signal from the RCA to the pot.
The sliver wire is the ground or shield wire. Goes from the RCA copper plate to that pot lug, then from the pot lug to the control board.
You can use a twisted pair, mini coax such as Belden RG316, or the original Belden cable that PL used as shown in the photo.
Many of us building or having built WOPLs bypass the signal attenuators (front pots) or leave them out all together.
My three S2 WOPLs have LEDs in place of the attenuators.
Click to expand...
great idea...i heard some put dcp led on front panel too....one for 110 and other no dc un outout!!!
 
dont understand why both channels...with either speaker connected...
try cutting input and output wires off their respective jacks/posts ... you need to change inputs since old ones are almost always problems...i got mine from watts when i ordered a dcp board...gold plated...and you need to change posts to install new posts with dcp board...
 
gene french said:
utting input and output wires off their respective jacks/posts
Click to expand...
I tried that when I removed the pots... I also checked the jacks, and they test fine as for grounding and connectivity.. sigh, I've hunted the schematic, and don't find any clue. Another cup of coffee, another pondering session.
 
gene french said:
dont understand why both channels...with either speaker connected...
try cutting input and output wires off their respective jacks/posts ... you need to change inputs since old ones are almost always problems...i got mine from watts when i ordered a dcp board...gold plated...and you need to change posts to install new posts with dcp board...
Click to expand...
Has me befuddled too.
 
Narrowed in on the issue. Removed both rail fuses and the dbt does not light with speakers attached. Replaced right fuse (as viewed from back of amp), and dbt does not light up with speakers attached. Removed left fuse, and BDT lights up with speakers attached. With left fuse still installed, removed each speaker one at a time, and DBT still lit up. So at least I now have a rail to trace.
 
interesting day...electrical storm yesterday struck both solar panels powering the internet microwave setup...had one extra panel....it is a 24v system...it should keep up unless we get several days of heavy clouds...gonna replace the two fried ones and keep the other as a spare..after holy week...everything shuts down...very catholic country...
 
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