Sotabeams speech compressor

Has any one brought a speech pro from Sota beams and has it improved the audio on your 857D looking to up the speech a little on my 847D with out going over board. IS it worth splashing out on ?

Karl 2E0FEH

Hi Karl, the FT857 has a built in AF speech processor which I find quite effective, and the FT847 has a built in RF speech clipper, so the Sotabeams processor would probably be over-egging it, though it looks useful for the 817 and I am considering it.

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I have one - definitely makes a difference for my on both HF and VHF SSB - using 5w from an FT-817.

Not sure about your 847 Karl.


I’m looking at one for my 817 too, by their nature, speech compressors will give more volume as they maximise the audio sent out… agree it may not make a difference if your tx has one already though :thinking:

Thanks guys this is of help


Hi Karl
I have one that I use with my 817.
In marginal conditions, the difference is very noticeable, tested many times with distant stations on-off-on and all report a marked improvement.

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I have one and it helps in marginal contacts. (FT 817). Also used it during the 80m CC contest (Ft 450)where it seemed to help get through. ( I could now work what I could hear! )

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I also have one, it works very well!

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I have one for my FT-817 and it has made the difference between making a contact or not a few times. Have used it on my FT-897 and it made the audio worse - the compression was NOT needed.

Howard KE6MAK


I do own one (purchased at Friedrichshafen) and it works well when the ft817 is barefoot and when used as a driver for transverters but when I’m using the 40w HF amp, combined with one of my antennas, I get distortion due to RF feedback, on some bands. Still working on “rectifying” that problem. Others in VK and G have reported similar issues.

Just as an observation, it is clear that the wiring in the mike, the curly cord and the patch cable between the compressor and the radio are all unshielded. And the compressor is in a plastic case, with a high gain amplifier circuit inside it. Perhaps no problem with the barefoot power from the 817.

I have asked the German supplier I bought mine from for any suggested cures - no reply received yet. I want to get it fixed because it makes such a big difference to the signal from the 817.

Andrew VK1DA/VK2UH


I’d be looking 1st at the unscreened networking patch lead provided to connect it to the FT817 then at the plastic case the processor is housed in.

Thanks to one and all for feed back.

Found the Proc on me FT857 and wound it up to 90% and check audio live via SDR hack green and it sounds good. A lot louder than before and few stations mention sounding louder than before. So result is what i want.

So not wasting money on one and investing in some copper wire and grounding stake for me new installed EF IN/L LF Tri Band wire antenna when in use at home and leave at home when take portable the ground and CP system .

One day get up Kitt hill and do some airing up there later’s in Year as want to air it on 160m as well prob late Sept time. Good thing about this antenna you can tune it 160 to 6m and 25m long. Lose about 7m on its vertical part and is replacing the OCFD 80m wire got at home and out preforms it too.



the FT-857D does not have a speech processor. Though Yaesu calls it a processor, it’s nothing but a simple amplifier.
So the result will be way better using the SOTAbeams (box73?) compressor.


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Whatever it is, it works well!