[R-390] Out of the closet!

[flowertime01 at wmconnect.com]

Paul,

R390/A's are house broken and very clean critters.

The lube of choice these days is a synthetic motor oil. Time was when you 
hung around a Mobil gas station and garbed an empty quart bottle out of the 
trash can. The empty bottle had enough lube in it to do a gear train very 
well. This story should give you an idea of where you need to go. Your new gear 
trains should be nice and smooth. Watch the little rollers on the cam 
frames and make sure they are all clean, lubed and rolling.

You want a good cap in the IF deck to protect the mechanical filters from a 
shot of full B+. 

You need to inspect all the big black fat caps in the IF deck and a couple 
under the RF deck. These crack and go bad. Mostly as plastic that just has 
not lasted 50 plus years.

There is a small electrolytic in the audio deck on the circuit board that 
like to leak. Go for an over size 10 - 20 UF replacement. The audio sounds 
better. It only need to be 25 volts as it is a cathode bypass. If you run the 
tubes until they fry then you can just replace the cap again.

Diodes in the Power supply save a few watts of heat.

If the ballast tube is open / missing and no sausage is on hand, the VFO 
and BFO filaments can be rewired to 6.3 volts AC in the IF deck to save some 
more heat.

Do not over mesh the split gears. One tooth to put tension on the spring is 
good. More is just grinding gears.

PTO ser No 1551
Dubrow Electronic Industries
Type 798 BM101
this label appears to be stuck over a different previous one.

This is just a contract rebuilt refurbish part. No problem.

Roger AI4NI</HTML>