If the filter bank is on the rear panel and the filter switch is on the
front panel, it sure sounds to me like that long, circuitous path could be
the problem. I'd try eliminating the filter switching and see if the
performance returns to normal. Also be sure that whatever surface the
connectors are mounted on have a very good and short ground path back to
appropriate place on the board.

Joe
W3JDR


Michael wrote in message
...
Hi,

I built the AN762 amp along with 6 low pass filters with parts bought from
Communication Concepts.

The amp itself (180W version) works fine and can easily produce 180W with
5W
input.

Now to the problem and question:

I wanted to put it in a good solid case with the filters, a RX/TX relay
(8A
240V Omron relay also bought at CCI) a manual switch for the filters and
the
filters.
I also found a good heat sink for the PA.

I connected all parts with short runs of RG-58, but a lot of the power
seems
to get lost in this system. If I'm lucky I can get 100W out. Even if I
bypass the filters. Is RG58 a bad choice for the internal wirering? Is the
manual switch a bad choice?
What special things should I address for optimum perfomance?

In my case the PA is placed on the back panel direcly mounted on the heat
sink. I made a rectangular hole in the back for the PA board.
The input and output connectors are also on the back panel. The filters
are
mounted at the bottom of the box and connected to a band switch mounted on
the front panel. Behind the filters and in front of the PA is the RX/TX
relay cirucuit.

73
de
Michael
OZ8AGB