[R-390] Receiver flavors.

[David Wise]

I thought I understood, but...  Confirm or deny, please: The VFO and BFO heaters are AC, with the whole circuit elevated to about +25V, not actual DC heater power.

(The phrase "hum-bucking" is messing with my head.)

Dave Wise

Elevating an AC heater circuit was a common practice in hum-sensitive applications.   It prevents heater thermionic emission to the cathode.

________________________________________
From: r-390-bounces at mailman.qth.net <r-390-bounces at mailman.qth.net> on behalf of Les Locklear <leslocklear at hotmail.com>
Sent: Sunday, July 26, 2020 5:56 AM
To: r-390 at mailman.qth.net
Subject: Re: [R-390] Receiver flavors.

Here is the story, from Henry Rogers at the Western Radio Museum here: http://www.radioblvd.com/MilitaryCommunicationsGear.htm
Scroll down...


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