[R-390] Further on problem getting my R390A working

[Roger Ruszkowski]

Ken,
 
Rustle up a few spare tubes and start testing them in place.
Cal Tones and the line meter will get the receiver up to best mechanical and electrical alignment.
 
A signal generator and two meters are just more elegant. 
 
Your mission is to grade the tubes in hand, cherry pick, Easter egg hunt, test tubes.
 
Set the receiver up and listen to some TTY.  idle and active  CW and modulated The world chooses your meter reading moment.
 
Run all the 6C4's and put your best three in the receiver. Second mixer above 8 Mhz.
In the IF deck and the 6BA6's in the R390 or the 5749's in the R390A get the same treatment. First IF amp
Run all the dual triodes through the audio deck and consider even grading each side if good tubes are not on hand.
 
Ask the children to fold you some Chinese finger cuffs in a couple different sizes. Use them as tube pullers. A couple lengths of 1/4 wide ribbon from a gift package works well.
 
If the tube lights up and functions it passes the short test. The receiver will let you cook a shorted tube for some time for slow speed educational demonstrations.
After you swap a few tubes you will start to hear the difference and get an ear for judging the best of two tubes.
There is a pecking order for the placement of a tube set into the receiver for the best use of the tubes in hand to yield the best sensitivity and signal yield.
 
Put your hand on the radio.
 
Fifty years ago the clamber was no room for all the needs. 
Wait until you can get some of the audio out of your receiver and into a computer sound card.
It is all their but it's different now. 
 
Visit  http://www.r-390a.net and http://www.r-390.com Different sites all of it is useful.
 
Respectfully,
 
Roger AI4NI