Twin D-500 Restore-a-Thon / Full-Comp WOPL upgrade (+ first a PL 400 S2 WOPLing / Proof of concept / Process debug )

Amen Dave, looking forward to your adventure...we are all standing by to help in any way possible..
 
I'll start.

You need a sturdy bench, with eye-searing light available. The bench I work on watches on, I have a 4-foot LED "shop light" I got at Home Depot. I bought two; however, one is more than enough! To control shadows, you may consider setting up in front of a window, and/or having your light come from several angles: Overhead, both sides- maybe one on a gooseneck, such as the popular IKEA one everyone uses for their truntables...
 
The Powerful Difference said:
Alright, a month ago I stopped lurking in this forum & introduced myself here.

****

It's time to set up the spot where I am going to document the path I will be taking through a couple of D-500s, a 400 S2, a couple of PL preamps, and (assuming that I haven't run out of steam by then), maybe even a PL 5xxx S2 AM/FM tuner I bought new, kept waiting for the break-in period to make it gel...and eventually gave up on it. (I've also got a couple of Lexicon surround sound processors that I enjoyed listening to/through, & they will need new caps also.)

Of course, before I even get to do that, I first need to brew up a no-kidding analog electronics workstation that will help to give me as much unfair advantage, project-wise, as I can fit into my project budget. (I actually *do* have my old Tek 475 o-scope, and I'm hoping to populate the rest of the workspace with the same/better level of audio equipment assembly/debug/performance measuring test gear.)

And if you were to read my intro, you will see that all of the above + my loudspeakers have all been parked in storage for over 2 decades, so I fully expect to have to go through every single item before I reach my eventual goal -- listening to music in order to make up for lost time...and to repair my battered soul. :0)

So, given all of the above, I decided that this picture best describes my initial starting point of this (admittedly) ambitious project:

View attachment 58631
(MC Escher's Drawing Hands)


Last & least, here's an older photo of me enjoying the sights & sounds of the big ditch:

View attachment 58632

Please be thinking of the very best way(s) to spend my money as we dive down this audiophile rabbit hole. :0)

Game on!
Click to expand...
I am a Puddle fan. Want to find a decent original someday...
 
Mayor McCheese was indicted in 1980 on counts of fraud and embezzlement. You don’t want him.

This is also why he has not been seen in McDeTh advertising since. Corporate wanted to distance themselves from the mayor.

Carry on.
 
The Powerful Difference said:
Lee, given that I'm proposing to take 2 scopes (+ new caps) and make 1 good one out of them,
I was hoping to find a quality troubleshooting guide.

Good news -- here's a period-correct Tek troubleshooting manual. I skimmed through it -- looks very informative.
NOTE: If anyone out there has a scope like this, I've attached the file to this posting FWIW.

View attachment 58641

Here's to happy Scope Doping!
:0)
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Thanks for sharing. I have two of these old workhorses
 
The Powerful Difference said:
Lee, given that I'm proposing to take 2 scopes (+ new caps) and make 1 good one out of them,
I was hoping to find a quality troubleshooting guide.

Good news -- here's a period-correct Tek troubleshooting manual. I skimmed through it -- looks very informative.
NOTE: If anyone out there has a scope like this, I've attached the file to this posting FWIW.

View attachment 58641

Here's to happy Scope Doping!
:0)
Click to expand...
Nice. I’ve got a 465 that seems quiffy. The CRT works and will show a center dot, I can move the dot with the horizontal and vertical calibration knobs and if I recall it will deflect with a signal but not correctly and I can’t get a trace. Pretty sure I had things set up correctly in that I should have at least seen something but she was a no go. I’ll have to trouble shoot it some time. Thanks for the guide.
 
The Powerful Difference said:
OK, for the handful of Tone Warriors following along, last night I introduced myself to the PL 400 S2 amp that I'm going to use as my 'proof of concept' for taking my vintage Phase Linear gear & making it better instead of worse.

It's going to get the honor of not only debugging the electronics workshop that I've yet to build...but also help me re-acquaint myself with the analog skills that weren't directly involved in making the mortgage payments the past 40+ years.

Seems like a lot to put on a small ~40 year old amplifier, but in the scheme of things I think that this is a good jumping-off point. (ie: To go from 0 > max effort, fully comp D500 is not a recipe for success.)

Without further ado, here's the upgrade candidate: PL 400 S2, Serno #22969, production ID sticker = " Darlene ".

View attachment 58716

Logo closeup:
View attachment 58717

Darlene scrubbed up good:
View attachment 58718

View attachment 58719

Background info: Bought this maybe a dozen years ago, made the purchasing AND gate based on a) not left outside/dragged behind 4-wheeler, b) essentially complete (but missing top cover) and c) really sold at a reasonable "as-is, no guarantees auction price".

The actual purchasing details are lost, but I think the auction + shipping < $100.

My goal(s) with this amp: See how far I can take it, performance-wise. (Think my control unit for when I do the Carver Null test against future upgrade candidates -- I'd like to be able to document in a lossless audio file where you can actually listen to the before/after audible differences of one/or all amplifier mods...so that you can best decide what to do based upon what matters to you sonically vs. all the FUD (Fear, Uncertainty, & Doubt) heavily trafficked across the interwebs. (!)

Also, come up with a cost-effective way to mitigate the visual ouch of the 4 rack-mount holes that somebody inflicted on Darlene. (Could be as simple as 4 button head allen fasteners -- you know, a subtle tip of the hat to her history without having to stare at the previous owner's hackery.)
NOTE: Visuals are arguably more important in the main system -- but we can relax the eye-candy standard on a workshop amp! :0)


So, I am actually building it for me. My plan is to be listening to this very amp through a pair of Infinity Qe bookshelf speakers mounted strategically in my lab workspace while tackling the 2 bigger Unicorns. Done correctly, thanks to the proposed sound reinforcement in my new workspace my productivity will be at/near my personal best.

So happy to be breaking ground. The cornerstone of this whole adventure is Darlene -- all I'm missing are the silver-plated shovels & Mayor McCheese...
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We have a cure for your faceplate woes, we can make Darlene into a pretty woman again.
 
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Triple D seems to have stuck, lol.
I am definitely looking forward to watching your progress and have the utmost confidence that these gents will get you over any obstacles you may encounter.
In your shop/lab build, I would throw this in for your consideration, I use a marine plastic called Starboard (HDPE) for my bench tops. It is impervious to most chemicals and very dense but is soft enough that it won’t mar any objects you place on it. I used 1/4 inch thickness on top of 3/4 inch plywood but you can get it as thick as one inch and it can be ordered in 4x8 sheets. D3E06F19-4DE8-4617-B197-274E108381A7.jpegEACDC9A4-4855-41A6-9C9A-FD053C95199C.jpeg556D31D0-246F-491C-8BE9-9B630F134862.jpeg
 
If you use that surfacing on your bench, be sure to put a grounded anti-static mat on top of it if you are going to do electronics repair. That polyethylene will hold a static charge like nothing else, superb insulator.
 
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