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Topband: 4. MFJ noise canceller

To: <topband@contesting.com>
Subject: Topband: 4. MFJ noise canceller
From: n1rj@pivot.net (Roger D. Johnson)
Date: Sun, 08 Dec 2002 18:11:13 -0500
Hi Top Banders....

 I've removed the hi-pass filters in my MFJ-1025 as described on
WA1ION's site. I did a quick measurement on 1800 khz and it seems
that the main channel is only down about 1 db. There is about a
1 db gain on 80m. I didn't have a chance to check the aux channel
today. When I had mine apart, I noticed that the bulb in series
with the aux input has a resistance of 50 ohms. Makes a nice divider.
I took the bulb out of mine and plan to switch the input to ground
using a small reed relay. I also removed the back to back diodes.
I don't live near any strong broadcast stations so I don't need the
HP filters and I don't want to chance any self QRM from the diodes.

73, Roger

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