[R-390] Mods vs. Changes

[Jim Whartenby]

AA4HAIsn't detection of a radio's location by DFing the leaky LO just urban legion?
I can see how a leaky LO can interfere with ELINT or a COMM center when there are many receivers located in the same room.  The loss incurred by back feeding through one or two stages of RF amplification should be enough to put the LO near the same level as the thermal background noise.  
Has anyone ever tried to connect two R-390As back to back to see if one can detect the LO frequency of the other?  The vans used in GB to look for unlicensed TVs was just for show and used to force compliance or so I have read.  See:  https://en.wikipedia.org/wiki/TV_detector_van
Jim

Logic: Method used to arrive at the wrong conclusion, with confidence.  Murphy 

    On Thursday, July 17, 2025 at 01:02:24 PM CDT, Tisha Hayes <tisha.hayes at gmail.com> wrote:   

 I have seen changes as updates to the design to substitute in different
components or to change the behavior of the radio.

Official mods may incorporate changes to the design to bring modules or
decks up to the most current revision. There are also a few mods to address
vulnerabilities (like detection of a receiver caused by a leaky oscillator
that can reveal the location of a receiving site) or for later
susceptibility to overcurrent.

A mod example would be the replacement of the rectifier tubes with diodes.
I think there was another with the PTO.

Then there are the entire special-build variants; For example the use of
Clevite ceramic filters for the IF deck (I have one of those decks).

*Ms. Tisha Hayes, AA4HA*

"Humans with AI; It'll be like Plyfoxians with a Slurb
Hail Soyka!"
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