[Milsurplus] ARC-2: Smart People Needed

[Richard Brunner]

>From all that has been said, I suspect what you have is what can reasonably 
be achieved with an IF of 1 to 1.5 Mc.  The old TRF broadcast receivers were 
broad too, which is one reason people went to superhetrodynes with an IF of 
455 or 262 Kc. to achieve selectivity.  The high range Command sets with 
high IF's were broad too.

Richard, AA1P

> Not having a schematic am being at a disadvantage and just tossing up 
> speculation at this point but isn't there a fixed frequency IF stage after 
> the variable IF? Know all the Collins stuff of the late forties and 
> fifties used a variable IF section and then a second converter to a fixed 
> frequency IF on 455 KHz for civilian stuff and frequencies like 500 and 
> 250 KHz for military radios. The filtering is always on the output of the 
> second converter.
> Now interested in seeing the schematic for the ARC-2 being that may be the 
> first radio to use the double conversion system and the father of the 75A, 
> R-388 and later S line radios.
>
> Ray F