[Drake] TR-4 and TR-3

[Garey Barrell]

Gary -

Right, I had forgotten about the manual T-R on AM and CW.  That's the 
only thing in your list that I believe to be a "functional" difference!  :-)

73, Garey - K4OAH
Atlanta

Drake C-Line Service Manual
<http://hr99.home.mindspring.com/R-4C_Servicez/>



Gary Poland wrote:

> I believe the TR-3 had to be manually switched from transmit to 
> receive in AM, and possibly CW. Its been a while since I have owned 
> one. The TR-3 and early TR-4 where pretty much identical otherwise 
> except for the 6JB6's used in the TR-4 instead of 12JB6's as with the 
> TR-3. The TR-4's continued to evolve with different SSB filters, audio 
> preamp stages, changes in the PA cage, T/R relays went to plug types, 
> some changes in IF and Mixer tube types, a plug for the 34PNB,  2 
> dials instead of one, etc.
>
> Gary
>
>