Carver C-4000 recapping

marcok

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#23
Przem,
I have the original C4000 service manual and I confirm that there's no component list .
In case you want to recap it I suggest to use this method :
Remove boards one by one and recap and after insert it and check always one by one .
It' s a long but safe procedure .
I made this with the two my father's PL 4000s.
Obviously before buy 10/15 caps from 1uf to 10uf .
Ciao
Marco
 

P.L.F.

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#24
C-4000 transformer secondary voltage

I found a candidate for the project, which will allow for keeping my current system intact -> see pics. :hello1:

However it is the US version with single primary transformer... pity... From something like 1982 Carver has adopted dual primary transformers for C-4000(t) but mine is from 1980, Oct 6th (BTW - marking inside is very detailed, nice!).

Now, my question is: should I look for a replacement with 2x15V on the secondary? Or 2x20V? Would 50watts be enough, as I am not intended to use the built-in amp for delay effects?

Anyone can help?

And in addition, I found a strange IC inside: Reticon SAD4096. It's not on the schematic of the delay PCB (only 4136 should be present there). Any advice why they put in this special and bloody expensive these days IC (>$100)?
 

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laatsch55

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#25
Probably to upgrade the 4136. You could use the Brown Dog adapter with the Burr Brown OPA 2134s on it.
 

marcok

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#26
Przem,
the transformer is 15 /0/ 15 100W .
If you don't use the power amp for time delay 50W should be sufficient .
All ICs are supplied at +12 / -12 V via series regulators .
Delay unit power amp is supplied at +22 / 22 V after the rectifier ( 22 is moreless 15 x 1.41 )
The Sad 4096 is a " bucket brigade " IC to perform time delay .
Very rare and very expensive .
Ciao
Marco
 

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#27
Przem,
the transformer is 15 /0/ 15 100W .
If you don't use the power amp for time delay 50W should be sufficient .
All ICs are supplied at +12 / -12 V via series regulators .
Delay unit power amp is supplied at +22 / 22 V after the rectifier ( 22 is moreless 15 x 1.41 )
The Sad 4096 is a " bucket brigade " IC to perform time delay .
Very rare and very expensive .
Ciao
Marco
Marco, you rock! Thank you Buddy, now it's clear. Ciao!
 

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#28
While waiting for the 230V / 15V-0-15V transformer, I recapped all PCB's. Here is the list of caps, which can be helpful in acquiring them before starting the job:

  • 2200uF x4
  • 220uF x2
  • 100uF x8
  • 47uF x2
  • 22uF x4
  • 10uF x5
  • 4.7uF x10
  • 3.3uF x1
  • 2.2uF x15
  • 1uF x16
To simplify you may go for 50V in all cases - it'll work well...
I also installed 230VAC IEC socket and cleaned /lubricated all switches, pots and RCA jacks.
TBC...


P.S.
I could not take out the aluminum faceplate though - is there a trick for doing that???
 

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marcok

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#29
Simply remove the four screws of the handles . The same as PLs series II .
( if i remember well ) .
I have seen you have removed the power amp for delay unit ;
remember that in this case the low level delayed outputs don't work , because the
signal is got from hi level out via a 20dB att.
The power amp is mono and left and right signal is the same , but out of phase.
Ciao
Marco
 

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#30
Simply remove the four screws of the handles . The same as PLs series II .
( if i remember well ) .
I have seen you have removed the power amp for delay unit ;
remember that in this case the low level delayed outputs don't work , because the
signal is got from hi level out via a 20dB att.
The power amp is mono and left and right signal is the same , but out of phase.
Ciao
Marco
Thank you Marco, good to know about the power amp of delay PCB! It will be back intact where it should be. As for the faceplate - I was suspecting it should be the same, but it wasn't. It looks like the jack socket for headphones keeps the faceplate veeeery tight and I don't want to force it too much... Or should I go hard...?
Ciao! Przem
 

marcok

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#34
Przem,
sorry I have forgotten the headphone jack .
Simply desolder it .
Ciao
Marco
 

marcok

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#35
28102014013.jpg

Here is my C4000 in black , made by a dud about 30 years ago .
The faceplate was anodized in black with a new silkscreen .
After I spray painted handles , knobs and switches .
Ciao
Marco
Ps: Prezem if you are in troubles with your C 4000 ,simply ask .
 

JustMike

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#36
View attachment 17135

Here is my C4000 in black , made by a dud about 30 years ago .
The faceplate was anodized in black with a new silkscreen .
After I spray painted handles , knobs and switches .
Ciao
Marco
Ps: Prezem if you are in troubles with your C 4000 ,simply ask .
Marco,
That is one beautiful C4000 buddy.
Jm
 

marcok

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#37
Thank you Mike.
Przem,
I have just seen that in "The Carver site" the C4000 service manual has been published .
I think it will be very helpful for you.
I also gave a wrong info about time delay unit power amp : it's stereo not mono .
The delay unit is mono and the phase shift unit is before power amp and not after .
Sorry , but after 30 years my memory ....
Ciao
Marco
 

laatsch55

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#40
Would one out of the original 4000 work. I have 4 of the damn things laying around.
 
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