New Member: Planning my PL400 rebuild

[mr_rye89]

I was able to pick up my 4 fin for $100 locally and it already had a WOAD power supply and Don's DCP board in it so......

I'm also on the hook for warranty so I accept the risk of having 4 less fins. For You guys who build em professionally I can see why you would avoid the 4 fins.

FWIW If Joe ever offered a pl400 heat sink kit I'd buy it (and I'd probably get a new chassis too)

 

[Mohawk]

I was able to pick up my 4 fin for $100 locally and it already had a WOAD power supply and Don's DCP board in it so......

I'm also on the hook for warranty so I accept the risk of having 4 less fins. For You guys who build em professionally I can see why you would avoid the 4 fins.

FWIW If Joe ever offered a pl400 heat sink kit I'd buy it (and I'd probably get a new chassis too)

Can't argue with that.... 100 bucks is a score for sure....

 

[mr_rye89]

Forgive the ignorance, but what are the "collector covers"?

I sympathize about the OCD. I have a related syndrome -- CDO. That's like OCD but the letters are alphabetical they way they were intended to be.

The covers for the output transistors, don't touch em they'll give you a tingle.....

 

[Mohawk]

 

[Mohawk]

And yes, the outputs will bite you if you insist on touching them.....

Zap....

 

[WOPL Sniffer]

Yeah, I don't run the covers on my amps either.

 

[MarkWComer]

Forgive the ignorance, but what are the "collector covers"?

I sympathize about the OCD. I have a related syndrome -- CDO. That's like OCD but the letters are alphabetical they way they were intended to be.

The spring steel covers over the output transistors on the back. High potential there- 160VDC on the 400, 200VDC on the 700. SERIOUS shock hazard!

EDIT:
From hand to hand, through the chest (heart!), is FATAL.

 

[jle]

The spring steel covers over the output transistors on the back. High potential there- 160VDC on the 400, 200VDC on the 700. SERIOUS shock hazard!

EDIT:
From hand to hand, through the chest (heart!), is FATAL.

Well, I'm glad to see that we eye-to-eye-to-eye-to-eye on this...

 

[mlucitt]

For You guys who build em professionally I can see why you would avoid the 4 fins.

The four fin PL400 is the earlier model. Most have the capacitors attached to the side of the chassis with clamps, while the later amps use an aluminum cradle above the transformer. There were other improvements in the later models such as the lighting arrangement for the meters. Most of the differences go away when the amp is upgraded with WOA Backplanes, a Rev G1 Control Board, and a LED Light Board.

 

[jle]

Thanks to all for the warnings about the inadequacies of the 4-fin heat sink. I have secured compatible 8-fin heat sinks and a transformer upgrade and will proceed with my now-fortified and much beloved original PL400 for the project.

Mohawk's mandate for "a clean and organized work bench" has proven to be my greatest challenge in preparing for this project. I am almost there. I have successfully upgraded the power supply for my Linn LP12 turntable so the benchtop is once again visible as that gets moved back to the music room. A Superior Electric Powerstat variable transformer arrives today. The ole Hakko soldering station has been retired and replaced with a Weller WT101N 95W. That should give me enough heat for the PEM solders and for roasting hot dogs.

That leaves me with just enough time to build the Watts Abundant DC protection board before my White Oak order arrives. I think I'll consider this my "get ready to get ready" message thread and will start a new topic for the build itself. Thanks again to everyone for advice thus far.

-Jon

 

[WOPL Sniffer]

Thanks to all for the warnings about the inadequacies of the 4-fin heat sink. I have secured compatible 8-fin heat sinks and a transformer upgrade and will proceed with my now-fortified and much beloved original PL400 for the project.

Mohawk's mandate for "a clean and organized work bench" has proven to be my greatest challenge in preparing for this project. I am almost there. I have successfully upgraded the power supply for my Linn LP12 turntable so the benchtop is once again visible as that gets moved back to the music room. A Superior Electric Powerstat variable transformer arrives today. The ole Hakko soldering station has been retired and replaced with a Weller WT101N 95W. That should give me enough heat for the PEM solders and for roasting hot dogs.

That leaves me with just enough time to build the Watts Abundant DC protection board before my White Oak order arrives. I think I'll consider this my "get ready to get ready" message thread and will start a new topic for the build itself. Thanks again to everyone for advice thus far.

-Jon

Great Plan man............. You will be amazed when you fire it up for your first listening test. I hope you have a worthy preamp since you will need something to feed the amp with...... Remember, "Garbage In, Garbage Out" so your system will benefit greatly from a nice quiet pre..... Now, if we could all agree on a perfect candidate to upgrade, but that's the fun of the hobby right???

You will be glad you got the old American iron "Variac" (commonly used name). Screw the Chinee junk transformers. I rework/restore/upgrade ALOT of vintage Variacs and the build quality is apparent the first time you use it. I prefer the units with the meters and I love love love the units with both Watts AND Amps and I like to find the older Simpson meters instead of the square plastic crap meters but you may prefer other parts. You'll enjoy the new Weller also. I've been running with the 80W irons and never had a failure and I solder quite a bit. And, even though the tips are expensive, I have been using the 2 sizes of chisel tips for years. Tin them often and crank up the heat for a minute before hitting the damp sponge and it will blast the impurities off the tip and then a fresh tin job before retiring the tip for the day.

 

[Hexis22]

Love those old three meter Variacs.

I’ve been casually looking for one to restore and use to replace my current Chinese junk.

 

[jle]

You will be glad you got the old American iron "Variac" (commonly used name). Screw the Chinee junk transformers...

Yep... it took me a while to find an American-made one within my budget. I had my heart set on a Staco but my wallet did not agree.

-Jon

 

[jle]

...I hope you have a worthy preamp since you will need something to feed the amp with...... Remember, "Garbage In, Garbage Out" so your system will benefit greatly from a nice quiet pre...

The first system the rejuvenated PL400 will power starts with a Linn LP12 (I just did the upgrade on its power supply), Linn Linto phono preamp, Denon preamp and Linn Akurate speakers. There's also a large subwoofer that must be made by a company called "Effin" because everyone who sees it says, "Wow! That's a big Effin subwoofer!"

But upgrades are underway there as well. I am restoring a McIntosh C22 Mk1 (probably 1964) -- it has three "cans" containing several capacitors each that is a bear to work with, but I'm in no hurry. And there's a ultra-low-noise phone preamp started (a bunch of SMDs to do, not my favorite, but otherwise a great design).

Then, in the afternoons...

-Jon

 

[NavLinear]

'Sniff has done his magic with the Variacs. I especially like the three meter General Radio beauty. Oh - and speaking of beauty here's a Nav welcome babe of your own. Welcome to the club.

 

[jle]

Not quite what I meant by "an American-made one within my budget" but I like the way you think

 

[WOPL Sniffer]

Love those old three meter Variacs.

I’ve been casually looking for one to restore and use to replace my current Chinese junk.

I scored another 5 amp 3 meter Variac that will get resto'd this winter. They are near impossible to find these days. If you see one, jump on it as they go quick and no "deals" are usually available.

 

[jle]

I rework/restore/upgrade ALOT of vintage Variacs and the build quality is apparent the first time you use it.

The Superior Electric Powerstat arrived today. It looks to be in excellent condition from the outside. The knob turns quite smoothly. I will do some light cleaning of the case with a paper towel moistened with some Sprayway. Is there anything else I should do? Like spray the innards with DeOxit? Or, if it ain't broke, don't fix it"!?

-Jon

 

[Gepetto]

The Superior Electric Powerstat arrived today. It looks to be in excellent condition from the outside. The knob turns quite smoothly. I will do some light cleaning of the case with a paper towel moistened with some Sprayway. Is there anything else I should do? Like spray the innards with DeOxit? Or, if it ain't broke, don't fix it"!?

-Jon

The latter...
I have an SE variac. Great American quality. I got mine for a song since the outer wrapper was slightly dented. A few minutes to make a wooden last in the circle shape and it was back to looking brand new again. Good luck with yours Jon

 

[mlucitt]

Thoughts on the Staco?