[R-390] Filters

[quartz55]

Someone indicated they would send me a few broken filters.  I'm going to see what I have on hand before destroying the 4K one I have any more.  If I can get it working with parts from another, so much the better.  If I find broken magnetostrictive wires on others, I may continue on with trying to see if I can repair the wires.

I'm still looking for more broken filters to play with.  What the heck if they're broken and we can learn repair methods?

I'll need to come up with a method of testing them, I have one of those function generator chips I've put in a box, don't know if it goes to 455, but it may, and I think I have some audio amps that may go up there to produce about 10V into 100K.