First PL-400 Restoration
- Thread starter dtafil
- Start date
Good to see people taking good care of PL400's. Just getting ready to do the same. I have a very early PL400 that I bought new. Build date 24th week 1972 S/N 17, Edmonds, WA. It had some serious issues in the beginning, something failed internally and blew up a set of Bose 901’s. Phase Linear repaired it under warranty and Bose did the same. I have been using it for the last 47 years with no issues, but I think it is time to do an upgrade with White Oak Audio and maybe I can get another 20+ years out of it.
Finally got started... blown away by the quality of the L14_20 RevE5 Control Board kit, including the labeled baggies and pre-formed leads. Top-notch all around. Got through the diodes and 1/4 watt resistors, will pick up again tomorrow night. Adding a pic of the "Pat" sticker from inside the amp...
Attachments
- Joined
- Jan 14, 2011
- Messages
- 74,939
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
- Joined
- Jan 14, 2011
- Messages
- 74,939
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
- Joined
- Jan 14, 2011
- Messages
- 74,939
- Location
- Gillette, Wyo.
- Tagline
- Halfbiass...Electron Herder and Backass Woof
It's been a good day.
Got the filter caps, control board installed. Brought up the amp as per instructions with the all new transistors row by row w/ my dim bulb tester and variac, and finally biased both channels to .350 VDC after warmup. Next steps are to install Don's DC protect board, and then looks like an LED lightboard upgrade, as I have no lights (meters swing to the right briefly at power on). Guessing it's not worth the effort to mess with the old light board unless someone has a quick suggestion.
Some pics with current progress. Can't wait to hear this thing!!!
Got the filter caps, control board installed. Brought up the amp as per instructions with the all new transistors row by row w/ my dim bulb tester and variac, and finally biased both channels to .350 VDC after warmup. Next steps are to install Don's DC protect board, and then looks like an LED lightboard upgrade, as I have no lights (meters swing to the right briefly at power on). Guessing it's not worth the effort to mess with the old light board unless someone has a quick suggestion.
Some pics with current progress. Can't wait to hear this thing!!!
Don's DC board is in, and the amp is alive!!! Pictures coming later tonight.
Quick question: can anyone recommend a person/link to grab some new RCA input jacks for this amp? Not sure if there is something typically used for these, but mine need to get replaced. I did get all new speaker outputs posts, all good there.
Quick question: can anyone recommend a person/link to grab some new RCA input jacks for this amp? Not sure if there is something typically used for these, but mine need to get replaced. I did get all new speaker outputs posts, all good there.