gslikker
Super Member
I decided to put progress here, for leisure. This is a very interesting amp. One of the first "computer-controlled" amps.
I presume they are that rare,probably only well-known in Germany.
The story started here....
My CV1500 has an input problem, probably a bad circuit card contact on the backplane, since the inputs are directly connected to the circuit card, making it prone to bad solder joints/pcb cracks...
In the end, it only works while pushing a bit on backplane connectors.
Now trying to open it up the proper way, I see almost burnt components, a lot of dirt (it is greasy inside, it was in a "less tidy" house when I bought it), and there is no easy way to loosen the back.
So what happened: I disassembed further, I ended up having a pile of cabling and pieces, the mid frame including transformer (which is also taken apart now).
This will be a time consuming and challenging piece.
I need to observe esd precautions due to the cmos chips, also. Also components made by companies I never heard of are in: NKL capacitors, SSS (Solid State Scientific) cmos chips. The UNOBTANIUM in here probably is the NS microcontroller, a COP420 preprogrammed device,
The first question for the opamp experts already arises: How is other peoples experience about the RC4559 opamp?
It is full of RC4559NB opamps, The only other restoration info I found is from the German dual-doktor.de site, they seem convinced they are prone to failure.
Now here are the leisure pics of the pile of funny circuit cards.
I presume they are that rare,probably only well-known in Germany.
The story started here....
My CV1500 has an input problem, probably a bad circuit card contact on the backplane, since the inputs are directly connected to the circuit card, making it prone to bad solder joints/pcb cracks...
In the end, it only works while pushing a bit on backplane connectors.
Now trying to open it up the proper way, I see almost burnt components, a lot of dirt (it is greasy inside, it was in a "less tidy" house when I bought it), and there is no easy way to loosen the back.
So what happened: I disassembed further, I ended up having a pile of cabling and pieces, the mid frame including transformer (which is also taken apart now).
This will be a time consuming and challenging piece.
I need to observe esd precautions due to the cmos chips, also. Also components made by companies I never heard of are in: NKL capacitors, SSS (Solid State Scientific) cmos chips. The UNOBTANIUM in here probably is the NS microcontroller, a COP420 preprogrammed device,
The first question for the opamp experts already arises: How is other peoples experience about the RC4559 opamp?
It is full of RC4559NB opamps, The only other restoration info I found is from the German dual-doktor.de site, they seem convinced they are prone to failure.
Now here are the leisure pics of the pile of funny circuit cards.
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