I just swept a Drake TV-1000-LP and Bud Variable Low-Pass Filter #LF-601
using an HP 8443 and HP141T with a 8552B and 8553B. The Drake goes from 0
dB at 51.3 MHz and drops to -50 dB at 57.1 MHz. While adjusting the Bud it
was kind of neat to watch the impact of each of the 5 varaible capacitors in
real time I got 0 dB at 41.7 MHz and 60 dB attenuation at 54.5 Mhz. I
didn't try to optimize the Bud for channel 2 as yet, that's next. I'm
guessing I'll lose the extra 10 dB attenuation the Bud provides but maybe
I'll get a sharper knee after I optimize it for channel 2 attenutation. My
question is what happens to the attenuated energy that the low pass blocks
as there are no resistors in either? I'm sure I'll see some surprises as
soon as I sweep both with my return loss bridge as soon as I find it.
Tnx
HankWD5JFR

it is reflected back. A small amount is dissipated in filter and its
construction materials, and spacing of shields to coils, silver is lowest
loss. I just found my return loss bridge in the garage, yesterday, in that
"pile of stuff that I could need someday".

"Henry Kolesnik" wrote in message
om...
I just swept a Drake TV-1000-LP and Bud Variable Low-Pass Filter #LF-601
using an HP 8443 and HP141T with a 8552B and 8553B. The Drake goes from 0
dB at 51.3 MHz and drops to -50 dB at 57.1 MHz. While adjusting the Bud
it
was kind of neat to watch the impact of each of the 5 varaible capacitors
in
real time I got 0 dB at 41.7 MHz and 60 dB attenuation at 54.5 Mhz. I
didn't try to optimize the Bud for channel 2 as yet, that's next. I'm
guessing I'll lose the extra 10 dB attenuation the Bud provides but maybe
I'll get a sharper knee after I optimize it for channel 2 attenutation.
My
question is what happens to the attenuated energy that the low pass blocks
as there are no resistors in either? I'm sure I'll see some surprises as
soon as I sweep both with my return loss bridge as soon as I find it.
Tnx
HankWD5JFR

On Sun, 11 Apr 2004 22:11:40 GMT, "Henry Kolesnik"
wrote:
My
question is what happens to the attenuated energy that the low pass blocks

Hi Henry,

Returned to sender - postage due (the source pays the penalty).

It never even makes it into the filter (such is the success of its
design). The mismatch could cause an arc over at the input port, but
then you have one nasty mis-behavin' transmitter (which is one very
good reason to use filters). The sense of "attenuation" is not so
much that the filter grinds down the rough edges, it is more that it
didn't fit through.

73's
Richard Clark, KB7QHC