SWR meter reading problems, or perhaps not?

Wayne Robertson

Hello, my 891 is showing high SWR on CW but oddly, not on SSB at the same freqs. Testing the antennas with analyzer shows them to be fine, as they've always been. Even a dummy load with SWR=1.0 on the analyzer shows high SWR on the rig in CW mode. What's up with that? Thanks, Wayne de K4WK

Joe K7JOE

#1384

You’re probably using an end fed something or other or maybe an off center fed antenna. The SWR In ca is probably common mode currents on the coax. Choke will usually cure that. Or you have an intermittent coax jumper.

Joe K7JOE

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On Sunday, January 31, 2021, 5:03 PM, Wayne Robertson <k4wk@...> wrote:

Hello, my 891 is showing high SWR on CW but oddly, not on SSB at the same freqs. Testing the antennas with analyzer shows them to be fine, as they've always been. Even a dummy load with SWR=1.0 on the analyzer shows high SWR on the rig in CW mode. What's up with that? Thanks, Wayne de K4WK

#1385

The swr on the 891 reads higher than what the true swr is, common on all the 891s

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On Sun, Jan 31, 2021 at 5:44 PM Joe K7JOE via groups.io <k7joe=yahoo.com@groups.io> wrote:

You’re probably using an end fed something or other or maybe an off center fed antenna. The SWR In ca is probably common mode currents on the coax. Choke will usually cure that. Or you have an intermittent coax jumper.

Joe K7JOE

On Sunday, January 31, 2021, 5:03 PM, Wayne Robertson <k4wk@...> wrote:
Hello, my 891 is showing high SWR on CW but oddly, not on SSB at the same freqs. Testing the antennas with analyzer shows them to be fine, as they've always been. Even a dummy load with SWR=1.0 on the analyzer shows high SWR on the rig in CW mode. What's up with that? Thanks, Wayne de K4WK

Wayne Robertson

#1386

But why on CW and OK on SSB? And, I qso'd on CW Jan 15 with no prob. Head scratcher.

Joe K7JOE

#1388

Hard to answer ‘why” without a lot more info on your specific station setup.

For example cheap Chinese crimp on RF connectors and lousy braid coax can be “ok” at lower power and “break down” at higher power. Same with various sizes of ferrite cores used in those 49:1 and 64:1 transformers. A 100W SSB signal may only allow duty cycle of 25W on CW, for example, before going bonkers. Tell us more about your station, accessories, antenna, antenna tuner, chokes being used, grounding, etc. We can then begin to speculate what might be causing the issue or identifying probable causes.

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From: Wayne Robertson
Sent: Sunday, January 31, 2021 6:33 PM
To: FT-891@groups.io
Subject: Re: [FT-891] SWR meter reading problems, or perhaps not?

But why on CW and OK on SSB? And, I qso'd on CW Jan 15 with no prob. Head scratcher.

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Wayne Robertson

#1389

Thanks Joe for the good list of parameters. As a preamble, the rig and its complete setup was fine in several CW qso's in first half of January. Last CW qso was 1/15 and it performed fine.

The setup is the 891 rig using the provided mic and for CW, a bencher paddle. Antennas are an OCF Windom that tunes up well on all bands without a tuner (confirmed by SWR on MFJ antenna analyzer) and for 20m and up, a small tri-bander. Both have fine SWR w/o use of a tuner. But, even with a dummy load with SWR=1.0, when connected to the 891 even that shows "HI SWR." The other really odd fact is that this is happening on CW but not on sideband.

So, I am suspecting some sort of CW setting that maybe I messed with but going thru the menu I see nothing likely.

Ideas?

Many thanks, Wayne

Joe K7JOE

#1390

How is the dummy load connected to the radio ? Is it connected directly to the antenna jack on the 891 or are you using it on a switch box, or in an antenna tuner, etc etc?

If there is any sort of coax between the dummy load and the radio, then the jumpers or patch cables could be suspect.

Again, not enough info yet. What kind of paddle you’re using (*or mic) is pretty much irrelevant here – more info on this dummy load you’re using…and patch cables etc are needed to find the likely problem location. It should be very easy to ID the problem once we know your setup in enough detail to see where the problem might reside.

.

Show quoted text

From: Wayne Robertson
Sent: Sunday, January 31, 2021 9:03 PM
To: FT-891@groups.io
Subject: Re: [FT-891] SWR meter reading problems, or perhaps not?

Thanks Joe for the good list of parameters. As a preamble, the rig and its complete setup was fine in several CW qso's in first half of January. Last CW qso was 1/15 and it performed fine.

The setup is the 891 rig using the provided mic and for CW, a bencher paddle. Antennas are an OCF Windom that tunes up well on all bands without a tuner (confirmed by SWR on MFJ antenna analyzer) and for 20m and up, a small tri-bander. Both have fine SWR w/o use of a tuner. But, even with a dummy load with SWR=1.0, when connected to the 891 even that shows "HI SWR." The other really odd fact is that this is happening on CW but not on sideband.

So, I am suspecting some sort of CW setting that maybe I messed with but going thru the menu I see nothing likely.

Ideas?

Many thanks, Wayne

85D248E51FDB46D5B5EBC9CEDBCFA254.png

Wayne Robertson

#1394

Joe, I’m out of town for a few days, reply soon, thanks.