[600MRG] Using the R-390A Below 500 kcs

[Kenneth G. Gordon]

I thought some of us here might find this information of more than 
passing interest. I know I do.

The same methods may be applicable to other receiver systems.

Ken W7EKB
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Subject: Re: [Milsurplus] R-390A Ops Below 500 kcs

Happy New Year from Chickenland. 

I've been playing with using the R-390A below 500 kcs which was suggested
years ago by Dr. Dallas Lankford in the "Hollow State Newsletter".  

As most of the R-390A owners have discovered the RF sensitivity drops off
very rapidly as you tune below 500 Kcs and the receiver is virtually 
useless as you reach 30-40 kcs below 500 kcs, depending on alignment.  

Anyway no major modifications have to be made and the receiver can easily
pick up signals all the way down to the 20-30 kcs region, thus adding a 
new band to your receiver. Sensitivity is excellent.  

You do not have to change the RF alignment. An external RF input tuning 
coil must be constructed as the RF section is completely by-passed. But 
don't panic you can use PVC and ABS as a coil form and the winding is not
difficult and makes you feel like you are doing some real radioing.  

Details on my web pages.

http://k4che.com/R390LF/R390LFVar.htm

k4che
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