I use this setup but I have the common port of the duplexer attached to the radio and the 2m port goes to the antenna. The second radio connects directly to the 70cm part of the Arrow.

That being said, my IC7100 will cause desense during TX on some RX frequencies for SO-50 on my TH-D74A. The Btech UV-5X3 or TH-D72 do not cause desense when I use them for TX.

On Tue, Mar 26, 2019, 12:24 skristof@etczone.com wrote:

Today, on the SO-50 pass, I tried using the Arrow diplexer (duplexer?) to enable full-duplex using two handhelds. As most on this forum know, if you use two handhelds with the Arrow antenna, the third harmonic of the 2m uplink will desense the 70cm handheld, so you can't hear yourself.

So, I hooked up what is normally the antenna end of the diplexer to the 2m uplink radio and the 2m radio end of the diplexer to the 2m part of the Arrow antenna. My hope was that this would suppress the third harmonic of the 2m uplink enough so that it wouldn't desense the 70cm handheld. The 70cm radio end of the diplexer was left unconnected.

It didn't seem to work. I made contacts but I still didn't hear myself on 70cm.

Just wondering if anyone else has tried this and what results you got.

Steve AI9IN

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