Newbie from Jacksonville FL.

[Quickcarl]

Found you guys a few years back while doing an internet search looking for info, on repairing my Phase Linear D-500. (It blew a gasket while playing Blue Oyster Cult at ludicrous level)


First, Let me give credit where credit is due.. yousss guys you have been so very much help already , just reading through your stories on upgrading the PL-700, 500 and 400’s helped me get my D-500 thru a healthy rebuild. Did all the caps, transistors and many of the burnt or out-of-wack resistors.


So Thanks to all many times over, for posting your test and repair experience for all of us to see. Especially the pictures. I’m a pictures kinda guy , ya know.


Back to the D-500: I have it up and running, for the moment it’s shaken the whole house. But, I want to change a few minor things. Such as update the face-plate. I want to go with a black front panel and black knobs and rack handles. Maybe come up with a way to darken around the meters slightly. (may have to break out the old airbrush and some satin black )


I have a few other phase linear and carver amps that need some serious help so I figured it was time the start talking to you guys.


Again, Many thanks for all of you guys Phase linear experiences.


Carl.

 

[laatsch55]

Bout time ya posted bud!!

 

[Quickcarl]

Procrastinator, it gets the best of me.

 

[laatsch55]

That particular trait gets easier with age...

 

[laatsch55]

BOC at Ludicrous is not a bad way to go...

 

[Quickcarl]

When the amp let go, it went full volume at what sounded like a 120 cycle hum. About gave me a heart attack. Had to turn it off to get it to calm down. When I turned it back on, no sound at all.

 

[laatsch55]

Ed could probably shed some light on that...

 

[Quickcarl]

This is an older picture of what I found when I opened it up. It had a few substitutions going on and a lot of heat damage. Since it was so old and I really didn't know the history I decided to replace all caps, transistors, op amps, overheated resistors and all diodes.

 

[oldphaser]

This is an older picture of what I found when I opened it up. It had a few substitutions going on and a lot of heat damage. Since it was so old and I really didn't know the history I decided to replace all caps, transistors, op amps, overheated resistors and all diodes.

QUOTE]

Carl,

Repairing Phase Linear Dual 500/D-500's is not an easy task. Do you have a copy of the service manual?

Perhaps it would also help if you could describe what you have in the way of test equipment and experience repairing audio gear. So that we can tailor our replies.

First off, I generally only repair Phase Linear equipment using those parts which were approved by Phase Linear and its former engineers and service department personnel. This is also to minimize the risk of the amplifier from oscillating.

It appears that from the photos you provided that a fair number of the semiconductors were replaced by unapproved parts:
1.) LF356 I.C.'s have been replaced with LF411's
2.) 40412V1's have been replaced with ?????
3.) Pre-drivers MM4003 and 40327 have been replaced with ????
If you have replaced them, what did you replace them with?

By the way, I hate repairing an amplifier after someone else has already messed with it.

I have attached some photos I just took a few minutes ago of a Phase Linear D-500 PL-32 pc board I recently restored. I also replaced a fair number of the 1/3rd watt resistors with 1/2 watt resistors. NOTE: The 1/3rd watt were also harder to read the color codes (with its salmon base color).


Ed

 

[Quickcarl]

[FONT=&amp]Ed,

Thanks for your time. I really appreciate it.

I would have posted this message, yesterday but right before i finished typing, the stinken power went off. Anyway...

No big concerns at this moment since I do have the D-500 back up and running, but I have some more work to do.[/FONT]

[FONT=&amp]In answer to your questions please don’t laugh at me too much when you read this.
My experience with electronic gear in general, was mainly limited to 3 years of repairing tube televisions and some antique radios. (mostly RCA and Zenith some Phillips ) This was way back in High School when they had decent shop classes, back in the 70’s. [/FONT]

[FONT=&amp]My test equipment consists of : Tektronics 465B O-scope, Fluke 77AN Volt Ohm meter, 20 amp variac, Weller WES51 soldering iron, Hakko FR-300 desoldering gun. PEAK Atlas ESR Meter and a Peak DCA75 transistor checker, Isolation transformer , miscellaneous stuff such as a pair of 250 watt 4 ohm load resistors. Astron power supply. Home-made Curve Tracer add-on for the Tektronics 465B (Slick little gadget).

Don’t have a signal generator yet, still looking. Do you have any recommendations? What are you using?[/FONT]
[FONT=&amp]
I do have the Dual 500 service manual and it has been a life saver.[/FONT]
I started on this D-500 repair project with a purchase 2 kits off of Ebay for capacitors and semiconductors . (shotgun approach) the rest I ordered from Mouser and outputs from ON..


[FONT=&amp]1.[/FONT][FONT=&amp]1. [/FONT][FONT=&amp]The IC’s are now 356,s [/FONT]
[FONT=&amp]2.[/FONT][FONT=&amp]2. [/FONT][FONT=&amp]The 40412V1’s replacements are now 2N3439’s [/FONT]
[FONT=&amp]3.[/FONT][FONT=&amp]3. [/FONT][FONT=&amp]The pre-drivers are now 2N5415(MM4003) and 2N3440(40327)[/FONT]
[FONT=&amp]Your right on, following behind someone else’s work, it made me a little nervous when I first saw that setup. (surprised it worked for a while)[/FONT]

[FONT=&amp]Thanks for the pictures or the PL-32’s those boards are nice. Wish mine looked like that.[/FONT]

[FONT=&amp]Here’s a picture of my reworked PL-32 board as it went back in. (sorry for the crappy picture) I am looking for a better one.



I had a few problems at startup. The Hi-frequency light would stay on. Now fixed - Found a blown diode. Then had a wire break on bias transisto,r which warmed up the amp a little. Fixed that. Set the bias at .45 VDC. Since I don’t have a signal generator yet, I skipped a few tests, for now.

Went ahead and connected it up the preamp and it worked (I got lucky) but I would like to finish the other testing as described in the service manual.

I noticed the LED display needs some adjustment, left channel shows a little low compared to the right. The adjuster for the left channel is maxed out. For now I will just turn down the right channel adjustment. After looking at the schematics it seems like many of the components are a little hard to find, all out of production. I do see a lot of Chinese clones.

1. Where do you find old transistors like the TIS97?
2. and the LED drivers such as the UAA170? Are there substitutes?

I just wanted to get a few spare parts before I work on the LED meter board.

For now it looks like this D-500 is off to a good start. I just need to find a decent signal generator.

Note: I have the Phase Linear fever now !! I ran out and purchased another Phase Linear, Dual 500 this time. So now I'm hooked. Haven't opened it up yet I'll wait a few weeks. After I get the bugs out of the D-500.



Carl[/FONT]

 

[laatsch55]

White Oak has new LED boards...check with Joe. What obsolete transistors do youneed?

 

[Quickcarl]

I'm looking at the Schematic (LED section)and the first offenders are MPS5172 the TIS97 and the TIS93. I cant find them at any of the trusted parts sites. The Ebay stuff all looks kinda iffy to me.



View attachment marked up dual 500 schematic.pdf

 

[laatsch55]

I have some 97's and 93's, Fairchild devices...

 

[Quickcarl]

Would you be willing part with a few? If so, just let me know how much.

 

[laatsch55]

Certainly.....10 cents each, how many??

 

[Quickcarl]

20 each, if you have that many to spare, that should last me a small lifetime.

 

[laatsch55]

PM me your address bud...

 

[marcok]

UAA 170 is available on ebay ( use Siemens ) 5/7 $ each
The equivalent for TIS 97 or GES 97 is BC 273B . Not always you can find Lee as supplier .
Already used on my father's PL4000 when restored .
Ciao
Marco

 

[Quickcarl]

Thanks for the parts info, Lee is setting me with the TIS97's, and I also ordered 2 of the UAA 170 from the Ebay seller in Bulgaria.

I am almost ready to open D-500 back up and change a few things.




Thanks,
Carl

 

[marcok]

Sorry , I made a mistake .
The transistor is BC 237B and not BC 273B.
Ciao
Marco