My understanding of the ARC-4 is that it was originally a Western Electric-designed commercial rig before WWII and was then picked up and used by the military before any subsequent better rigs were designed and put in service.
And I agree with you: 10 uV sensitivity isn't all that bad for a rig with no RF amp.
Although I have never yet had an opportunity to use one, I suspect it has unnecessarily bad "publicity" associated with it by some inexperienced hams.
I would respect K4CHE's ideas on this matter, and would like to hear what he has to say about it.
Ken W7EKB
Sent via the Samsung Galaxy S21 5G, an AT&T 5G smartphone
-------- Original message --------
Date: 7/20/25 11:12 (GMT-08:00)
Subject: Re: [Milsurplus] ARC-4
10uV input for 50mW audio output doesn't seem all that bad for a receiver with no RF amplification. Was this a civilian aviation VHF transceiver drafted into the military early in WW2? I seem to remember that the ARC-4 was in service before either the ARC-1 or ARC-3, but you know how memory can confuse things!
Jim
Logic: Method used to arrive at the wrong conclusion, with confidence. Murphy