[QuadList] TR-600 Headwheel amp transistors-retrofit? (Need Service Bulletin)

[Guy Spiller]

I'd be interested to know if those headwheel MDA power transistors in a 
600 are actually discrete transistors.
The capstan MDA in these TR-70Cs uses an integrated circuit in a power 
transistor case...and so far, I have had zero luck in finding any of 
them.  I have one that either was dead long ago, or blew on powerup.
I don't have the manual with the part number with me right now, but it's 
something like an MCB2000 or close to that.
What is the semiconductor type in those headwheel amps?
Guy

Ted Langdell wrote:
>
> On Sep 10, 2009, at 1:08 PM, Steve Greene wrote:
>> Re the TR-600, be careful with the headwheel power amps (three 
>> identical boards).  Each one used two big Motorola power transistors 
>> that are almost impossible to find.  They would commonly blow on a 
>> power surge.  I think RCA had a late technical bulletin on how to 
>> retrofit those boards for commonly available transistors, but I never 
>> found that particular bulletin again.
>>  
>> Steve
>> Steve Greene
>
>
> Perhaps our long-time RCA Service man Gary Adams may have what's 
> needed in his collection.  He's at IBC in the daVinci booth now, but 
> might be able to chime in from Amsterdam.
>
> Also, folks could compare TR-600 boards and see if there are 
> differences using commonly available transistors.
>
> Ted
>
> Ted Langdell
> Secretary
> Skype:  TedLangdell
> e-mail: ted at quadvideotapegroup.com <mailto:ted at quadvideotapegroup.com>
>
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-- 
Guy Spiller
email: quadruplex at verizon.net
phone: (804) 379-2050
website: www.GuySpiller.com
Midlothian, VA