[ARC5] Tuned circuits - # of coils (Was BC-455 selectivity).

[Kenneth G. Gordon]

On 27 Oct 2014 at 9:49, Leslie Smith wrote:

>   To Ken I ask: in the transformers you refer to (with "only one coil in
>   them") couple the signal to the following stage by mutual induction?
>     If not, how is the signal coupled to the following stage?

Well, at this point, Les, it appears that my memory was faulty. I doubt if there 
ever was even a modified version of an IF can with only one coil in any 
ARC-5 receiver I have or had.

This despite the fact that I no longer have even one "pristine", receiver, or 
even any that would be considered restorable.

ALL the ARC-5 gear I have has been hacked.

I even have several R-23(*)/ARC-5 receivers which have been "modified" to 
tune 22.8 Khz. Ripped to shreds, is more like it.

I know I have seen amplification circuits in which there is no real transformer 
between two tubes, but only a "peaking coil" or tuned-circuit, coupled by two 
capacitors, but I was wrong about the 2830 KHz IFT.

All original ones have two coils, although in the 7277, 7278, 7279 IFTs the 
coils cannot be separated for greater selectivity.

Ken W7EKB