Another Phase Linear 400 Series one rebuild thread

Sunnbobb

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Bikes, baseball and big amps.
Hi gang. I thought I should start a thread to consolidate my questions rather than spreading them all over the website.

I have a very nice condition 400 series 1 that I am working on. So far I have ordered the Relay output from Watts Abundant, and new Filter capacitors, Bridge rectifier, Neutral bar, and LED light board from White Oak. I have also ordered some HKP 15A fuse holders from Future Electronics.

Today I freed up the main board, expecting to see a PL14A or B board, but instead found the board in the picture below. After doing my due diligence soas to not waste the time of the fine folks here, I could not find anything about this board.

The Board is marked "Phase Linear" 14 55600. I suspect someone here might have a story about this board? I've attached pictures of both sides of the board, as well at the transformer information plate.

The second question I have is regarding the paper/cardboard shield that sits over the fuses and such. This amp is missing most of it. Is it a critical part, and what is it made of?

Lastly, I would like to use the optional switch for adjusting the sensitivity of the meters when I install the WO LED board. I'm looking for some ideas on how others have mounted it.

Again, thanks for your helpful insight,
Respectfully, Richard
 

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It's a PL14 Richard.

The shield is usually made of fish paper, an impregnated fiber material

Above the RCA inputs and below the output binding posts on the same centerline.
 
the chassis from white oak has predrilled for the sensitivity switch...it is located in the space between output posts and input jacks...i did all of my others to match...
i found it a good idea to change the rca inputs to gold plated...not too expensive...the original ones gave me fits...
 

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Thanks Gepetto. The only pitures I could find had the 14a or 14b printed on the board, so I was unsure. The remaining bit of the paper on my amp is directly above the fuses. Is the shield needed?
 
Thanks Gene, looks like a good place to retrofit the switch. Will it fit under the Output relay from Watts? I don't have the board from them yet, but thought I could go ahead and premount the switch.
 
Thanks Gene, looks like a good place to retrofit the switch. Will it fit under the Output relay from Watts? I don't have the board from them yet, but thought I could go ahead and premount the switch.
the dcp board will come with extensions ...that will lift it above a swich or the wo back planes...
you should install switch before dcp...
you will enjoy the quality of wo stuff...
 
Thanks Gepetto. The only pitures I could find had the 14a or 14b printed on the board, so I was unsure. The remaining bit of the paper on my amp is directly above the fuses. Is the shield needed?
Not needed as long as you don't fiddle around in there while it is live. The metal lid takes care of it.
 
Don, the entire thing is almost mint. I lucked out on this one. Even the printing on the outside of the cabinet is bright and intact. There wasn't even dust in the cabinet. It had a nice nicotine coating on the outside that cleaned off well. I fired it up on the dim bulb tester together with some throw away speakers and it seems to be operating great. I am going to do the minimal this go around eg output relay and filter caps, and see how it goes. I'll toss some more pics up in a bit.
 
The Board is marked "Phase Linear" 14 55600. I suspect someone here might have a story about this board? I've attached pictures of both sides of the board, as well at the transformer information plate.
The Phase Linear 14 control board pre-dated the PL14A and the PL14B control boards, naturally, and carried P/N's 55600 and 92600. Your control board, P/N 55600, came either uncoated or "coated" in a conformal or epoxy sealant common to most modern circuit boards of today. I don't know which of these two, coated or uncoated, control boards came first. Maybe some of our former Phase Linear employees can chime in. I thought the PL14 series control boards were early production although your PL400 Serial Number dates to later production from the newer Lynwood, WA Phase Linear factory.
Oddly enough, I have two of the "coated" 55600 control boards and they both have the factory 100uF/6.3V electrolytic capacitors installed backwards.
 
The Phase Linear 14 control board pre-dated the PL14A and the PL14B control boards, naturally, and carried P/N's 55600 and 92600. Your control board, P/N 55600, came either uncoated or "coated" in a conformal or epoxy sealant common to most modern circuit boards of today. I don't know which of these two, coated or uncoated, control boards came first. Maybe some of our former Phase Linear employees can chime in. I thought the PL14 series control boards were early production although your PL400 Serial Number dates to later production from the newer Lynwood, WA Phase Linear factory.
Oddly enough, I have two of the "coated" 55600 control boards and they both have the factory 100uF/6.3V electrolytic capacitors installed backwards.
Now that is some great info!
 
New fuses ordered from Future Electronics came in 5 days.
 

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Wrong fuse holders. You want solder tabs or lugs, not Faston connecters. You can drill those holes out though.
 
I have a 55 gallon drum of it if your are interested in some!
I got so much stuff engine wise kicking around I’m drawing a blank as to whether or not I have any Lucas electric parts on anything right now... if you do are you sure 55 gallons is enough? You might want to hang o to it!
 
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