[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: DEM 2400RX-144 results?



David:

Don, W4VQA and myself have been using both for some time. Don has done quite
a bit of comparison using mostly experience, a well tuned ear, and some
creative test gear. At first, I cut the stubs on the 3733s and we used them
like that. We found the gain was good but the noise floor was pretty high.
Then I bought a couple of Toko dielectric filters and Don modified both 3733
units by disassembling the filters, bridging the first filter with a piece
of its finger stock, and adding the Toko dielectric filter in place of the
second. We posted the procedure a couple of days ago under the subject
"TransSystem 3733 mods". After he did the 3733 mods, Don concluded that the
3733 was several dB better than a DEM. We got the same results on two 3733s.

Tomorrow I'll be taking both a DEM converter, and my modified 3733 to work,
and putting them on the signal generator/spectrum analyzer to see if I can
come up with more definitive gain and noise floor measurements for both.
I'll post the results in the next day or two.

Don also ordered the DEM LNA preamp today. After it arrives in a couple of
weeks, we'll have another round of comparisons to perform.

Stay tuned....

73,
Art N3OY and Don W4VQA

----- Original Message -----
From: David Reinhart <wa6ilt@bellatlantic.net>
To: <amsat-bb@AMSAT.Org>
Sent: Monday, June 04, 2001 8:52 PM
Subject: [amsat-bb] DEM 2400RX-144 results?


> Anybody using the Down East Microwave 2400RX converter without a
> preamp?  The specs say a noise figure of less than one dB and more than
> 20dB of gain.  That's much better than even a modified Drake without a
> preamp.  Any real-life reports?
>
> David Reinhart
> wa6ilt@amsat.org
>
>
> ----
> Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
> To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org

----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home