[ARC5] Selectivity and the BC-455

[Kenneth G. Gordon]

On 24 Oct 2014 at 20:35, Brian wrote:

> I don't think there is a single-coil IFT in any 6-9 mcs Command Rx, whether
> ARC-5 or SCR-274-N family. All the circuit diagrams I have for both show all
> IFTs with two coils. 73 de Brian, VK2GCE.

I'm sorry to disappoint you, Brian, but you're wrong. The 2830 IF cans I have 
here, most from early BC-455s (as I remember it), have only one coil in 
them.

The late R-27/ARC-5 IF cans I have here have two coils in them.

It has been awhile since I had a "40 meter" IF can apart, so I may have that 
backwards, but in any case, it is true that there are some with and some 
without 2 coils.

It was very common amongst early hackers of "ARC-5" gear to complain, 
repeatedly and at great length, that finding schematics which accurately 
described their particular receiver was "problematic" at best.

If you would like, I will send you photos of the two different "species" so you 
can see for yourself.

Although what with Photoshop being available these days, it is not really 
wise to accept photographic evidence as being incontrovertible, I don't have 
Photoshop.

Ken W7EKB