On Sun, Jan 08, 2006 at 01:24:14PM -0500, Jimk8mr@aol.com wrote:
>
> For most, if not all, of the many years I've had my DEM 432-28 transverter
> I've been bothered by a swath of crud covering much of the useful 432 band.
> Being about 2 miles from a tower loaded with pagers, two FM broadcast
> stations, and who knows what else, I kind of figured I just had to live with
> it.
>
> Recently, however, I've taken another look and determined that the offending
> stuff was the mixing product of a TV channel 23 visual carrier (525.26MHz)
> and an FM station at 93.1 MHz creating the FM signal at 432.160. The
> amazing
> thing was that the TV station is 30 miles away and the FM station 10 miles
> away.
>
> Yesterday I was able to check things with a FT-847, which was clean, and
> also to add a DCI 435-10 bandpass filter in front of the DEM transverter,
> which
> also cleaned up things.
>
> This seems like very poor front end performance in the DEM transverter.
> Have other people experienced this problem? Any suggestion as to what might
> be
> going wrong with mine if this is not a normal condition? The transverter
> otherwise seems to be working... the several birdies I could hear on both
> rigs
> seemed even stronger on the DEM than on the FT-847 (and went away on both
> with
> the antenna disconnected).
>
I have this same problem with my DEM transverter - I have not tried a
bandpass filter yet but I have thought of doing something like that
over the past year.
--
George Fremin III - K5TR
geoiii@kkn.net
http://www.kkn.net/~k5tr
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