On Tue, 15 Feb 2005 13:09:37 GMT, "Harold E. Johnson"
wrote:

I still haven't found my stray resonance in my MRF-150's that causes the
gain dip at 32 MHz. Haven't looked real hard for it since it's so eminently
flat from 2-30, it's just that it's also useable on 50 MHz and there's just
a little 4 dB droop that comes right back up above 35-36 MHz. What with the
state of the solar cycle, and with what my age for the next one will be, I
suspect I shouldn't be so concerned about it.

I'd take a look and a grounding issue. Last I played with MRF150s I
forgot to ground the top to the bottom side of the board right where
the leads intersect (the hole wher ethe MRFs meet the heat sink).
A peice of .003 copper shim stock from the top to bottom at the hole
fixed it along with a few places in the board (#18 wires from top
ground to bottom ground) seemed to clean it up. Then I first
encountered the problem I thought it to be a device lead length
problem on the input or output. HIgh RF current at low imedences
can really show things you'd never notice at lower power.

Allison
KB1GMX