I have not accurately measured the losses yet, but I am interested in
minimizing them.
The application is a 50Mhz-150Mhz 300W SS linear for ham use. The diode I am
using
is the Microsemi (Unitrode) UM2110. I am not paralleling the power side as
the power
is within the capability of the diode/package. Preliminary tests show the
transmit
side working FB (minimal losses, no heating, no resonance in ham bands).
I have not checked linearity yet.
The layout (I think) is good, tight, good ground plane.
The DC blocking caps are 1500pf Unelco metal clad mica.
By hold off voltage, do you mean reverse bias voltage?
In this application, the diode's intrinsic region is huge, so very little
reverse
bias is required, but since I am using the same control circuitry as I used
for
my larger HF design, the reverse bias is -160V.
My concern for losses comes from what I have heard from various people.
Microsemi/Unitrode
claims they can be minimal < 0.2db, but I want to hear from anybody who has
worked with this
stuff as to how they can be minimized on the receive side.
73,
George K. Watson
K0IW
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