Speech Compressor for FT-817, 818

(Inc. Tax)
(Ex. Tax)

NOTE Customers outside the Eu pay the lower (Ex. Tax) prices!

(30 reviews) Write a Review
Calculated at Checkout
Bulk Pricing:
Buy in bulk and save

Speech Compressor - unleash your DX potential

Version 3 replaces the obsolete SSM2165 compressor chip with the improved SSM2167

***apparent improvement can be up to 6dB!***

Available ready-built or as as an easy-to build kit. Build time approx 40 minutes

817に効きます! その差は歴然。JH4DUQ - via Twitter

The FT-817 FT-818 is a great radio but the SSB speech power does lack "punch". This great little external AF dynamic compressor from Germany Box 73 will aid readability and maximise the performance of your radio (essential when using QRP). Speech Compressors work by raising the average level of your audio signal, giving greater "talk power".

Plug and Play! Connects between the radio and microphone (lead included). The compressor function can be switched in or out, the module draws its power directly from the transceiver (approx. 10mA). The compression level is adjustable. Modifications to the microphone or transceiver are not required.

Click here for instructions.

The compressor is also suitable for use with the FT-900, FT-857, FT-897 and FT-450 (all versions)

Note: Speech Compression is not recommended for use on FM. 

Also available from: 



30 Reviews Hide Reviews Show Reviews

  • 5
    Speech Compressor

    Posted by Ray carpenter on 19th Jul 2018

    I got my speech compressor for ft817nd this morning over the moon with it thanks


  • 4
    FT-817ND Speed Compressor

    Posted by Unknown on 12th Jul 2018

    The compressor seems to working well. I would suggest better guidelines/help for the interactive adjustment with mic gain in the 817, mic level in the compressor and compression level. There must be better guideline available for a standard step by step procedure. The case would be improved with two small holes suitable for a jewllers screwdriver for pot adjustment without splitting ithe case. The plastic taps on the RJ-45 plugs on the interconnect cable are very susceptible to damage and should be protected, they are a weak link in the design. Other than that, first reports are good and I am optomistic.

  • 4
    Sotabeams speech compressor

    Posted by M3HME on 12th Jul 2018

    Brilliant little gizmo makes my 5 watts seem more

  • 4

    Posted by sv2oyo on 12th Jul 2018

    it is nessesary if you don’t want to keep your voice ...loud...it is useful ..

  • 5
    Speech Compressor for FT-817, 818

    Posted by Chris Maxwell on 11th Jul 2018

    Great product, easy to construct and easy to use.
    Gave me plus Two "S" Points in use.

  • 4
    FT817 Speech processor

    Posted by Andy on 5th Jul 2018

    Works well, does what it says on tin, only thing did find was using a local mini loop there was a slight increase in background noise on 7MHz, but considering the aerial only 2 feet from rig and the unit is unscreened this would be expected.

  • 5

    Posted by TERRY on 1st Jul 2018

    This works well with the 817, 857 as I have both radio's and did see a lot of difference when in use.

  • 5
    It Does What They Says it Will Do

    Posted by VE5KC on 5th Mar 2018

    I looked at several options for improving my signal on SSB. It seemed that some kind of speech processor add on was needed for my FT-817..

    There are several options available from modifying your microphone or adding a circuit in the rig. I didn't feel comfortable with modifying my radio. The Sotabeams (inline) speech compressor looked to be the answer.

    I ordered the Sotabeams speech compressor ,from England and it arrived at my QTH two weeks latter. It was easy to install, only requires plugging it in between the radio and microphone.

    The first thing that was obvious, according to the power output meter on the 817, I was putting out more power. On air tests confirmed that I could be heard much better ,with the Speech Compressor making a big difference. It easily gave me the one S unit or better of improved signal as claimed.

    My first few contacts gave me reports of some audio distortion and comments that I was driving the mic too hard. You need to remember (I forgot this in my hurry to test it out) to adjust the microphone audio level for use with the compressor! ) My normal mic setting without the compressor was 50. With the compressor inline, it works best set to 30.

    I am happy with the Sotabeams compressor, it does what it says it will do and gives a better signal.

  • 5
    It Makes such a difference!

    Posted by Dave Lucas G8XDD on 24th Feb 2018

    The Sotabeams speech compressor does make a great difference when running QRP. I had 3 qso's this afternoon with my FT817 on 80metres, 2 of which recorded me and played it back. It makes 2 clear S points difference said one of them. Can't wait to take it out portable on some SOTA summits.