[R-390] Trouble Parts

[Perry Sandeen]

List,
There are two items that can help you greatly in your receiver care/restoration.
First is the Y2KR3 manual, especially chapters nine and up.  Roger R. has graciously written long, easy to understand step by step procedures to help one both solve problems and do proper calibration.
I was fortunate to be trained on the R390A and got to work on them for 18 months.
It's not a simple receiver. One needs to take time and read to avoid endless frustration.
Second I produced a R390A two sheet schematic called "The almost ultimate R390A receiver" that I offered and sent to many on the list. (Still available)
On it besides good modifications, is a list off all the most troublesome parts.
A lot of my mods are based on the works of others, but there is a great emphasis on tube protection by slow filament and B+ warm-up.
True there are multiple millions of receiving tubes available but what we use is probably .0001 percent of those made. And they aren't making making any more.
Regards,
Perrier