Phase Linear 2000 troubleshooting

Coldsmoke

Coldsmoke

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Hello there,

I am opening a new thread for the other problem I face with my system.
My PL2000 has the following issues :

- Poor channels separation : I followed the service manual and adjusted and cleaned all the inputs / outputs jacks.
- No ambiance : the manual suggests a replacement of Z2 (4739) an Q1 (GES97)
- Tone control malfunction : replace Z3 (4136)
- Noise in phono circuitry : replace Z1 (4739)
- Plops when turn on and off : place the necessary caps

I read a couple of threads about opamps upgrade here and there but I'm not sure where I can find these... (I mean the right opamps...)

Thanking you in advance,
 
Last edited:
There is no replacement for the 4739's. There is a "Browndog" adapter for the 4136 consisting of a DIP with OPA 2134 surface mount op-amps on it. Google "Browndog Adapters".
 
laatsch55 said:
There is no replacement for the 4739's. There is a "Browndog" adapter for the 4136 consisting of a DIP with OPA 2134 surface mount op-amps on it. Google "Browndog Adapters".
Click to expand...


Sorry Lee, I think I wasn't clear enough, my point was : where can I find this replacement chip? I think I read that it was possible to get it soldered from the net...
Same for the GES97, I do no not really trust the websites giving equivalencies for transistors...
 
laatsch55 said:
There is no replacement for the 4739's. There is a "Browndog" adapter for the 4136 consisting of a DIP with OPA 2134 surface mount op-amps on it. Google "Browndog Adapters".
Click to expand...

Hum... Excuse me again, but if my 4739's are dead, does this mean that I can throw my beloved 2000 away...???
 
Coldsmoke said:
Sorry Lee, I think I wasn't clear enough, my point was : where can I find this replacement chip? I think I read that it was possible to get it soldered from the net...
Same for the GES97, I do no not really trust the websites giving equivalencies for transistors...
Click to expand...

Ok, I think I found where to buy it mounted.... but the 4739's..???
 
Is it the op-amp that is bad? Leaky caps make noises too. This one is old enough where bad passives are very possible. I'd be checking that stuff before replacing op-amps.
 
gadget73 said:
Is it the op-amp that is bad? Leaky caps make noises too. This one is old enough where bad passives are very possible. I'd be checking that stuff before replacing op-amps.
Click to expand...

HEllo and thanks Gadget.
All the electrolytics have been replaced by audio-grade components by the previous owner.
 
laatsch55 said:
I've only used the 2134's, I have some 4739's (used) , if you need some...
Click to expand...

It's very kind of you Lee, but I suppose that if 2134 is good enough for you, it will be for me. But I was talking about OPA2111AM as a replacement for the 4739's
About the GES97, does it has a direct equivalent?
 
TIS-97 fairchild, I have a few thousand of those too....
 
Coldsmoke said:
It's very kind of you Lee, but I suppose that if 2134 is good enough for you, it will be for me. But I was talking about OPA2111AM as a replacement for the 4739's
About the GES97, does it has a direct equivalent?
Click to expand...


The 4739's are a very weird duck. I have tried quite a few in it's place and they always oscillate. Joe tells me it has something to do with bandwidth and phase angles. We were going to rework the circuit on a 2000 to accept a different op-amp one of these days but so far have not done it...
 
Would you sell me a couple of 4739's and maybe a 97 or two?
I'd love to bring this thing back to life...
 
laatsch55 said:
The 4739's are a very weird duck. I have tried quite a few in it's place and they always oscillate. Joe tells me it has something to do with bandwidth and phase angles. We were going to rework the circuit on a 2000 to accept a different op-amp one of these days but so far have not done it...
Click to expand...

I would love to WOPL my 2000 too :)
 
Coldsmoke said:
Would you sell me a couple of 4739's and maybe a 97 or two?
I'd love to bring this thing back to life...
Click to expand...


I certainly would. I would also suggest ordering some sockets for the Op-amps...
 
laatsch55 said:
I certainly would. I would also suggest ordering some sockets for the Op-amps...
Click to expand...

Certainly. If you think about anything else that you have in stock and that would be usefull for the restoration of the preamp, do not hesitate.
If you have a paypal account, name your price in PM and I'll transfer you the money right away.
 
Or for my WOPL 400, I'm considering installing a DC protection (or fuses but I can't find any proper socket)
 
laatsch55 said:
Need a DC protect board too??
Click to expand...


I think I understood that it was a wise precaution, and I read here and there that fusing the cables could alterate the signal (If I could have figured how to mount these fuses I would have give it a try...)
 
I have a few 400 DC protect boards. Was just going to put one together for BubbaH's 400, I'll build 2.
 
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