VA6AM Triplexer

P1130798_smallIn order to use the spiderbeam @DL2LSM in parallel on several bands I’ve been looking for a triplexer. Looking at several approaches both commercially as well as homemade, I stumbled across the work of Pavel, VA6AM. He has been developing a triplexer with respectable performance numbers. Additionally, he provides printed circuit boards, parts, as well as entire triplexers. I opted for a full assembled board. It arrived in good conditions. DL2LSM did his usual mechanical magic to mount it in a suitable enclosure.

On air testing with QRP power level has been done during the CQ WWDX SSB and CW contests in 2015. It worked pretty well despite the fact that the unused ports haven’t been terminated correctly with 50╬ę but grounded and no additionally band-pass-filters were used. It is pretty amazing to listen to a station on 15m while transmitting on 20m at the same time.

System Pictures:

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System Performance (as measured by VA6AM):

BandInsertion LossVSWRStopband Attenuation
20m<0.15dB<1.04>44dB (@15m), >50dB (@10m)
15m<0.16dB<1.07>30dB (@20m), >30dB (@10m)
10m<0.13dB<1.1>45dB (@20m), >30dB (@15m)

Numbers for the stop band attenuation are worst case. The appropriate notches are pretty narrow. Thus, exact attenuation changes drastically across the bands. See plots for details.
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This entry was posted on Wednesday, April 27th, 2016 at 9:57 pm and is filed under Technical Article. You can follow any responses to this entry through the RSS 2.0 feed. Responses are currently closed, but you can trackback from your own site.

One Response to “VA6AM Triplexer”

  1. Low Power HF Triplexer | VA6AM Projects Says:

    […] DK3WE won the 1st place in 2015 CQWW CW QRP using a bare-foot-no-BPF attached VA6AM triplexer. Please, see his website. […]