[R-390] R-390 Digest, Vol 106, Issue 2

[Drew P.]

Quartz55 wrote:

"I have 2 R-390As.  Filters in one module seem fine, but the gain drifts, I'm working on that.  Other module has bad 2(weak) and 4(dead) but the 8 and 16 seem good, but different gain through them.

Was wondering if anyone has come up with a good cheap way to replace the filters?  Could it be possible to make an op-amp variable bandwidth 455 filter to replace the mechanical ones?  Don't know the voltages involved in the filters, but maybe too much for op-amp filters?

Is there any way to search the archives?"

Go to http://r-390a.net/Pearls/index.htm and there you will find nicely distilled and categorized information.

Drew