[AMRadio] New monthly AM operating event

[Donald Chester]

Rob K5UJ wrote:

> One advantage to the D104 as far as this is concerned, is its designed
> roll-off at 3 kc.

Actually, it's more like 5 kc.  The broad presence-rise bump is centred around the band of frequencies between 3 and 4 kc and then it cuts off sharply above 5, but people tell me they can hear the  difference between when I  run my audio wide open without any low-pass filter, and when I switch in the nominal 6 kc filter, which actually begins to roll off at 5 kc, with nothing  detectable on the scope beyond 7.5.

Under extremely congested band condx or when there is an adjacent QSO 5 kc away, I  switch in the sharp cut-off, brick wall filter @ 3400~.  That's also what I use whenever I operate at 7295.  I never try to operate any  higher than that, even  with the filter in line.

Don k4kyv