[TenTec] C21 RF Amp Mod, as promised!

[Josh Gibbs]

Huge thanks to Ed, W3NR, for sending this to me! It is a hand written
letter to 'Tom' (not sure who this is) from Ten-Tec dated Feb 13, 1978.

>From Ed:

"I also have a hand written how-to on adding a pre-amp to the RX. I did
this mod also and it made a remarkable improvement to the C21's
sensitivity on all bands, most noticabbly on 10-15-20. This how-to is
dated 2-13-78 and was written by Dick Frey W1FCC/K4XU then the Chief
Engineer at Tentec."

You will find the 3 handwritten pages here:

https://drive.google.com/drive/folders/0B_pjAwEfeYcdQlQ3OVpwbW9xVm8?usp=sharing

You will also find two interesting articles that Ed sent me. Both are from
73 Magazine:

*Little Extras for the C21 (73 Magazine, 08 August 1979)
*AGC, PDQ (73 Magazine, 05 May 1986)

Enjoy!

73,

-Josh WA7FPV