Juat acquired (very slightly used) ICE "BCB Filter Assy." Model 402X.
Installed with an in/out switch in the RX line to my TS940S.
For the first time in 5 years at this QTH I can actually HEAR signals
other than 30-over-9 BC crud on my transmit antennas on 160 and 80 meters.
On 160m the antenna is a 1/2 wave bent sloper, top at 100 feet. On 80m it's
an inverted V at 90 feet. I'm just listening in daylight so I won't know the
full effects till tonight. But the difference is quite dramatic on the few
signals available on 80/160.
Checking on the fundamental frequency of several local BC stations, and
using the S meter in the 940, the filter cuts down signals at the high end
of the BC band 20-25 DB (stations on 1290, 1450 and 1590 khz were checked)
and more on signals lower in the band (50 db on my closest station, 1150
khz, only a mile and a half away, which i suspect caused most of my problems).
I didn't get any paperwork with the filter, but the label says "1.8-30 mhz,
300w". Anyone familiar with this -- is it a bandpass filter for that range
or a high-pass filter cutting off below 1.8 mhz? Since it apparently is
rated for 300w, does anyone use it on the output of the transceiver, and is
there any benefit in that (if it's a bandpass filter, perhaps it would cut
down on TVI harmonics, for example).
There is a ground terminal, but I didn't see any difference when I
connected/disconnected a ground wire (the shack here is on 3rd floor, using
Faraday shield ground down 25 feet or so).
73/Jon AA1K
(no financial interest here in ICE)
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