TA-200W replacement (Kenwood KR-9600)

From the KR-9600 manual, a schematic of the power pack without specifics. Years ago I recall seeing hybrid schematics for STK and other units but I can't recall any Kenwood or Yamaha specific drawings.
 

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Solution TA-200W

I take post from "alhaynes" member of DiyAudio, i made it and works great
i use the darlington cople of transistors: STD03P and STD03N, is easy to made, feel free to ask.
Here's the schematic - very simple. Outputs are darlingtons, the bias diodes are included in the package. Rbias could be 200 ohm trimpot, typically ends up in 10-30 ohm range. The outputs are mounted on the back of the board against the heatsink. The 330pf caps probably compensate for the airwiring. And I know the circuit is a little over-protected.
Prototype 1 used the SAP15 transistors which include the emitter resistors - but the SAPs are out of production. Prototype 2 used parallel pairs of STDs, but stability, or rather docility, was an issue - probably due to wiring.
Funny, it's been 40 years since I've done any power amp work (other than repairs) and very little has changed.
Even funnier, the pad that I used to jot down the rough schematic is the same one I used in college - 40 years ago !
I've included a schematic of the KR-9600 output board, but it's a bit hazy. Anyway, pins 1 & 10 are power, pins 3 & 8 are drive, 5 is output, 6 is ground.
 
It would be nice to make a pcb.
I made a replacement STK-0050 module for the folks at the AK Pioneer forum. They are using them in the SX-780 and some Fisher models.
We have saved a few from the landfill :)
I simulated the design in ltspice.
One member has made up the Al plate to mount the pcb on, it attaches to the existing heatsink. The plates are being sold on eBay and I have made the BOM available at Mouser.
 
What do pins 4 and 7 do in the original chip?

Is your circuit based on what was originally in the 200W chip?
Or did you design this from scratch?

Thank you
check out post #11 under
http://www.diyaudio.com/forums/soli...circuit-amplifier-overview-2.html#post5365362
I take post from "alhaynes" member of DiyAudio, i made it and works great
i use the darlington cople of transistors: STD03P and STD03N, is easy to made, feel free to ask.
Here's the schematic - very simple. Outputs are darlingtons, the bias diodes are included in the package. Rbias could be 200 ohm trimpot, typically ends up in 10-30 ohm range. The outputs are mounted on the back of the board against the heatsink. The 330pf caps probably compensate for the airwiring. And I know the circuit is a little over-protected.
Prototype 1 used the SAP15 transistors which include the emitter resistors - but the SAPs are out of production. Prototype 2 used parallel pairs of STDs, but stability, or rather docility, was an issue - probably due to wiring.
Funny, it's been 40 years since I've done any power amp work (other than repairs) and very little has changed.
Even funnier, the pad that I used to jot down the rough schematic is the same one I used in college - 40 years ago !
I've included a schematic of the KR-9600 output board, but it's a bit hazy. Anyway, pins 1 & 10 are power, pins 3 & 8 are drive, 5 is output, 6 is ground.
check out post #5 under
Wide range of unreliable Amp Models with SANKEN's SAP/STD Series - Why ?
 
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great info folks keep it going

There are going to be a good handful of these that need the love and they are truly one of the most handsome units of the 70s .. a great project to restore no question .. i had forgot to mark this thread since my last post cant believe how much i missed in 2 years
 
I'm an amateur audiophile and this is my first post.
If you can't find a replacement TA-200W power amplifier, what would happen if you soldered in transistor STD03P in slots 1 thru 5 and soldered transistor STD03N in slots 6 thru 10? Would it work, or major damage?
TA-200W are virtually impossible to find, there must be a way to engineer this problem!
 
Found source for TA-200

I just found this group looking for a TA-200 output module for a kenwood, and when I found a source for them for as little as $9.99 I have to share. I found them at Alibaba.com here's the link if the moderator allows it. On Alibaba some suppliers require large quantities but many will let you order only one. Look over all the vendors to find what you need.

Ta-200w Suppliers, Manufacturer, Distributor, Factories, Alibaba

Good luck
 
I've bought from Alibaba in the past including some ASIC miners, usb hubs, routers, 12 volt 30 amp power supplies (for mining) and have always received new products. I bought a lot of assorted MOSFETS and they were all good. Some of the TA-200s listed showed Kenwood logos on them. It's worth a try for something that's almost impossible to find.
Lou, the DooWopRocker
 
Hello Kenwood folks

I have been asked by a member if I can make up a TA-200W module, like we did for the STK-0050 as used in the Pioneer SX-870.
If anyone is interested, let me know, I may consider making one up.
As we did with the STK-0050, it would be advantageous to have another member, with a KR unit to work with, so we could figure out the design details and test it out. I do not own a KR unit that uses a TA-200W.
I will need a TA-200W(dead or alive) in hand or measured up in order to even start.
It might take a while but I think it is feasible to do this one up and put some new life into the old units.

Rick
 
Mine is in pieces with several parts of it powdercoated but still awaiting reassembly - will be a long long time. Though I know exactly where it is (as opposed to the 1000's of others that I don't).
Anyway I will be lining up to buy one if you get it made.
Cool.
Srinath.