DIY Project - Nytech CPA602 today ...

[NRWler04]

Gentlemen,

while recapping my old Nytech Amps CPA602's we decided to bring the Amps to the state of the art from today. I already started to design an new housing pink fish media - View Single Post - Recapping of Nytech CPA 602 and to design a new PSU board.

Any further Tips and suggestions how to improve the old Nytech in the ghost of Mr. Hay are warmly welcome ...

The idea is, to design mono-blocks based on the nytech Amp.

Help is appreciated

[lohk]

Do you know the schematics Mr. Hay used for the Ion Systems amps? For a new amp I would probably follow that road and let the Nytechs untouched (besides the recommended recappings and some minor repairs and cable mods etc.).

[NRWler04]

Originally Posted by lohk

Do you know the schematics Mr. Hay used for the Ion Systems amps? For a new amp I would probably follow that road and let the Nytechs untouched (besides the recommended recappings and some minor repairs and cable mods etc.).

No, in pinkfish there are some .... do you have some? Would be helpfull ....

[lohk]

I should have them all - including the nexus, the x-overs and the tuner. I was once repairing those amps for my country for some time. I should scan them and post them somewhere, but that is a lot of work due to the oversized plans maybe. Please remind me if I keep on forgetting..

[lohk]

I do not have the schematic of the CPA602s, although I think there is little difference to the CA252s. Do you have them?

[NRWler04]

Originally Posted by lohk

I do not have the schematic of the CPA602s, although I think there is little difference to the CA252s. Do you have them?

I have the schematics for the 602 in the latest design with the tumb Reduktion circut and I have the schematics of the 252. The "S"-Edition I dont have ...

Would be wunderfull If you can scan the ION's it and pm it to me ...

Grüße aus dem Ruhrgebiet

[NRWler04]

The new PSU-Board for dual channel power supply is finished. Will fit into the original housing, place for two 120VA Toroids still available. Can also be combined with the original one ....

[NRWler04]

There are some news....

The housing prototypes are available .....

http://i.imgur.com/pdQIc.jpg?1

http://i.imgur.com/rcxTR.jpg?1

[NRWler04]

Please see also here: Recapping of Nytech CPA 602 - Page 2 - pink fish media

[NRWler04]

Gentlemen .....

Some steps are already done and I'm very interested in your feedback, comments and your further ideas ....

I designed new housings for the new CPA 602-2012.





There is also a new designed PSU PCB:



The PSU PCB will fit also in the original CPA602 housing. I have three of them and all will get a new PSU-PCB with two 120VA 58V Toroids. They have a diameter of 92mm and will fit into the original housing. Then I have CPA 602's in complete Mono-Design

And the Block Layout for the new housings is also available:



The idea is now, to prepare new PA-Boards which can be used also in the original 602 and my new housing.

Before I do this, I want to optimize the circuits. The original one I transfered into Eagle. Here are the orginal schematics. Please look for failures ...I'm sure there are some ....



Things I discussed with alohka and already changed are:

Ceramic Cap's: All ceramic caps were changed to Foil and Styroflex. I used WIMA FKP's with 1% and Vishay Roederstein MKP's 1%.

Cap #5 was changed to 470µF. This is the value the later Ion Obelisk had for this cap ....

Output Caps: I have already 4700µF 63V Axial Caps in my 602's. My idea is to implement an option into the PCB to use 5 Radial cap's instead of the orginal axial. What I found so far are Nichicon FW 2200 µF 63V. Maybe there are better one .... This will only work in the new housings; enough place will be available. Maybe this will work also in the original housing ... the 2200µF have a diameter of 18mm and a high of 35 mm .... I have to find out.

This are the Cap's I want to use:



I replaced also the both Piher with Trimmer from Vishay:
VR1 - 100k: Vishay Trimpot T93 YA - 100k
VR2 - 220: Vishay Trimpot T93 YA - 220

This is what I did so far. The schematics are transfered and nex step is the routing. Before this, your ideas to improve the logic and the components are warmly welcome ...

Regards from Germany