[Drake] Drake 2-C question

[Garey Barrell]

Ron -

I've run into this before.   There are at least two versions of 
schematics for the 2-C, 0007 and 1000, but both show 12BZ6.

If you have priced the 12BZ6 lately (or back in the late 60's) it's 
always been an expensive tube, and difficult to find.

The second (1000) version of the 2-C is dated 8/67 and still shows 
12BZ6, and the first R-4B (7000) is dated 9/67, and shows the 6BZ6.....

Likewise, the TR-4 had the 12BZ6 up to 27000 (9/67), then 6BZ6 from 
27500 (4/68).

By the way, there is at least a couple of R-4/As out there with 6BZ6s 
even though the chassis says 12BZ6!  Very easy to move the filament wire 
from 12 to 6!

If the "only working band" happens to be 3.5 to 4.1 MHz, keep in mind 
that the 2-C, like the 2-B, is an 80M receiver with a crystal controlled 
converter in front!

73, Garey - K4OAH
Glen Allen, VA

Drake 2-B, 4-B, C-Line&  TR-4/C Service Supplement CDs
<www.k4oah.com>


bonddaleena at aol.com wrote:
> Hi. I received an e-mail from a chap that had recently acquired a 2-C
> receiver. It 'kinda' works on one band. In suggesting some of the usual
> suspects, a strange fact has emerged.
> His radio uses a 6BZ6 tube as the RF amp. My radio has a 12BZ6. He sent
> me a pix of his chassis and it is indeed stamped "6BZ6".
> My info and schematics indicate a 12BZ6 was used there. Now the
> filament transformer does have a center tap, so it's possible that
> Drake made a running change.
> My ser # is: 085X and his is: 163X.
> He is going to measure the fil voltage and get back to me.
> If Drake did indeed switch to the 6BZ6 later in production, what would
> be the reason?
> Cost, performance, heat, availability?
>
> This one's got me scratchin' my gray head...
>
> thanks!
>
> ron
> N4UE
>
>