[1000mp] Roofing Filters
Thomas Beltran
tbeltran at earthlink.net
Sat Dec 25 22:57:39 EST 2004
Winston, I haven't sold my IF mod kit yet, its been sitting here since
August or so, when I got the roofing filter kit. But I agree, and I think
you'd agree, it would be nice to have both, and not have to choose between
them. Just knowing that Rob Sherwood has some involvement in this thing,
I'm hoping that there might be a switching kit for the MP, like Rob's mods
for the Drake R4C.
(For those not familiar, Rob has had switched First IF roofing filters for
about 20 years, 600 hz for CW, and 2.4 khz. USB and LSB, switched from a
small relay control board that fits inside the radio - there is a
replacement double-duty knob that replaces the AGC knob (which came out more
recently), so that the larger rear knob switches the AGC positions, and the
smaller front knob switches the filters - very elegant. It was nice to see
some of this 20 yr. old technology applied to the Yaesu.) Rob has the
results of his testing, and those old R-4Cs of bygone years make a good
account of themselves.
Since the connections for the Inrad filter and IF mod kit are exactly the
same, it doesn't seem like such a thing would be sooo difficult [easy for me
to say]. There is certainly a lot more room in the Yaesu, than in the
Drake. When I wrote to George over a year before coming out with the kit,
raving about how well Sherwood's stuff worked, he said that he had been
working on it, but a roofing filter of any real selectivity seemed to be
impractical in the Yaesu, because of the high IF frequency. But he did it,
and maybe not a "must have" as some might say, but it works quite well. So,
I'm saving my IF kit, hopefully, I'll be reinstalling it with a switch kit.
Certainly there is a business motivation also, instead of an either-or,
every MP owner could conceiveable own (and use) both. Sign me, "holding out
for the switching kit." Tom W6EIJ
More information about the 1000mp
mailing list