[R-390] Mechanical Filter Repair

[Dennis Pharr]

I'm afraid I already know the answer to this, but does anyone know if it's
possible to repair the mechanical filters in the R390A?  I was listening to
my R390A EAC last night when the 4kc filter failed.  

Before anyone asks, I had already replaced C553 before I powered up the unit
the first time, so that's not the problem.  All the other filters are
working OK.

I would appreciate any information anyone has on this.  I know replacement
filters are available, but the price seems a bit excessive ($175 ea.).

73,
Dennis Pharr
WD5JWY