817 speech processor

Has anyone any experience of any of the audio compressors such as the W4RT One Big Punch for the FT 817? I’m thinking that something to improve the talk power of my portable setup would be a good investment. An in-the-mike processor is lighter than an external PA!

I’ve no intention of paying half a ton for one ready made when the bits and pieces to make one are only buttons. But as I’d have to buy a slack handful of ICs (minimum quantity is 5 I think) and they’re tiny little surface mount blighters I don’t want to go to a load of effort for something that doesn’t make much difference.

If you’ve ever used one, or if you own one, or if you’ve had a QSO with someone using one, then please let me know.


In reply to MM0FMF:

I did have one of those inline ones (cant remember the name) for the 817 at one point. I dont know whether it was incorrectly built or set up, but the audio reports ranges from appalling to extremely appalling. I only used it twice.

I have read that others have used the succesfully though and that the OBP does work but I have no experience of that one.


In reply to 2E0HJD:

I only paid £225 for my 817 2 years ago and that included a mains PSU and a softcase aswell as the original Yaesu battery and a set of 1.8Ahr NiMHs. The component cost for an audio processor based on the Analog Devices SSM2615 comes to less than a fiver.

But if you know where to get 857’s for £329 new then I’m all ears! :wink:


In reply to MM0FMF:

I bought the One Big Punch, but had horrible RF feedback problems, especially out /P. Tried everything, but never cured it.

Eventually I bought a DF4ZS RF clipper instead.

Much better. The One Big Punch is just an AF compressor. This is a proper RF clipper.

I’m very pleased with it. It’s superb on 2m SSB. On HF, it’s best with the barefoot '817. My 25W PA is a bit underbiased so it can sound a bit rough I’m told (I never intended to use the PA on phone - then along came 5MHz). Having said that I only turn it off when I’m on 2m FM.

When I fitted the new clipper into the mike I also added a small tone oscillator, to persuade the rig to put out a carrier to check the SWR or tune the antenna when on SSB.

If you want to try a sked and have a listen, I can plug it in at home. Probably 5MHz daytime would be best if it’s in the right mood.


In reply to MM0FMF:

I have a OBP for my ft817 and it would appear to make a worthwhile improvement. It shows a distinct increase in average transmit power on a power meter. It definately makes contacts easier than without it.


Tryed a 1 big punch in backpackers contest 2 years ago on a palls ft 817. worked well with no problems. and no bad reports.

73 dave

I have a DYC-817 which I bought second hand recently. Not had it long enough to comment how well it works but I bought it on the back of the reviews at DYC-817 Speech Compressor.

In reply to G8JGQ:

I have a DYC-817 which I bought second hand recently. Not had it long enough >to comment how well it works but I bought it on the back of the reviews at >DYC-817 Speech Compressor.

I also use the DYC-817. It works very well and its quite a different to “only” microphon. Other stations on SOTA-activations told the signal-strength went up abt 2-3S (say from 55 to 57/8).
The only problems is the wire(cable) which breaks very easy on /p-operations. You have to fix it with zipties (cable-fixer).
Vy73 Fritz

In reply to MM0FMF:
I am running the DF4ZS RF-clipper with my FT-817 and FT-7. It works great. No rf problems, good audio and it gives me 2 more steps on the s-meter. By the way, Analog Devices has stoped in December 2006 the production of the IC ssm-2165 wich is used in the OBP or DYC. 73´s Uwe.

In reply to MM0FMF:
It’s worth setting up the radio (in the hidden menus) to match your voice. Improvement can be made over the stock settings.
Not that I’ve bothered with mine (either of them…) so far.

Graham G4FUJ

In reply to G4FUJ:

I have followed this thread with interest and maybe I’m just lucky, but I always receive good audio reports on my 817, which is standard, except that I have set my own Mic settings in the menu.

73 Mike GW0DSP

In reply to GW0DSP:

Thank you all very much for your thoughts and comments.

Like you Mike I’ve never had bad audio reports but I’m more interested in increasing the audio talkpower. I’m prepared to accept a compressed and clipped sound for the apparent improvement it can give to chasers when I’m not a brilliant signal.

I knew the SSM2215 was now obsolete but IIRC the SSM2216 is still available. This is essentially the same as the 2215 but has more pins and is more configurable. The OBP and similar designs are still available so perhaps the manufacturers did a lifetime buy. The German DYC-817 looks to be a fine deal at $22 (about £11) and looks to be the best value of the audio compressors. As I said I was going to make my own as the components were only pennies but seeing the DYC-817 includes the PCB and a case for such a tiny extra outlay it would make sense to get one of those to play with.


In reply to MM0FMF:

Sounds a good buy to me Andy. With my preference being towards cw I have never considered a proccesor for the 817, but always get good reports when on 60m-ssb. I took the lazy route and use my 857/7ah SLAB if intending to do 80/40m-ssb and find that the QRO does the trick. Having said that, I only do the “tiddlers” and might change my views when/if I manage to progress to the 2 pointers.

73 Mike