Poor voice modulation on Icom 802 ssb

[Sulaire]

A few months back i posted regarding a tx problem on my icom 802, the help i received was great, now i have crossed over the atlantic and am in puerto rico, looking to head upto the Chesapeake,i have been trying to contact Chris Parker weather on ssb. When i try to make contact with Chris he emailed me back saying the signal is strong enough but just noise nothing recognisable as a human voice! I hear all the other callers and he is loud and clear too.

The saga continues, luckily I had iridium go and have to say it is a fantastic system, but i do like my ssb nets!

Any ideas? Again,no voice modulation but a good strong signal.

Thank you in advance.

[S/V Illusion]

Originally Posted by Sulaire

A few months back i posted regarding a tx problem on my icom 802, the help i received was great, now i have crossed over the atlantic and am in puerto rico, looking to head upto the Chesapeake,i have been trying to contact Chris Parker weather on ssb. When i try to make contact with Chris he emailed me back saying the signal is strong enough but just noise nothing recognisable as a human voice! I hear all the other callers and he is loud and clear too.

The saga continues, luckily I had iridium go and have to say it is a fantastic system, but i do like my ssb nets!

Any ideas? Again,no voice modulation but a good strong signal.

Thank you in advance.

Not that it’s important but it’s deviation, not modulation, on an FM signal which determines voice quality. While it’s possible something has caused the deviation to change, it may be something as simples as a bad microphone or bad cable or connector.

Rather than the typical guessing game we often read here regarding problem definition, its pretty simple to diagnose a deviation problem with the right equipment which is certainly available in PR. I’d start with a new microphone or at a minimum, check the pin outs on the cable.

[GILow]

Originally Posted by Sulaire

A few months back i posted regarding a tx problem on my icom 802, the help i received was great, now i have crossed over the atlantic and am in puerto rico, looking to head upto the Chesapeake,i have been trying to contact Chris Parker weather on ssb. When i try to make contact with Chris he emailed me back saying the signal is strong enough but just noise nothing recognisable as a human voice! I hear all the other callers and he is loud and clear too.

The saga continues, luckily I had iridium go and have to say it is a fantastic system, but i do like my ssb nets!

Any ideas? Again,no voice modulation but a good strong signal.

Thank you in advance.

Google voice compression and clipping on the 802. Depending on the age of your radio you may need to make some minor changes to the radio. A software setting, from memory, and in some cases the addition of a resistor or two.

Also search this site, it has been discussed a lot and one poster who goes by his call sign (can’t remember it right at the moment) describes the problem and solution.

Edit : it was ka4wja. He’s got lots of info on these radios and if you google his call sign you’ll find what you need. I am about to do the same to remind myself.

[a64pilot]

I have often wondered why there is no better Mic available for the 802, an after market Mic, the factory mic just doesn’t impress me.
A bit like the factory speaker didn’t either, but there are better speakers available, I went with a clr speaker noise canceling and it’s much better than the factory one.

If there is a better after market mic, I can’t find it.

[S/V Illusion]

Originally Posted by a64pilot

I have often wondered why there is no better Mic available for the 802, an after market Mic, the factory mic just doesn’t impress me.
A bit like the factory speaker didn’t either, but there are better speakers available, I went with a clr speaker noise canceling and it’s much better than the factory one.

If there is a better after market mic, I can’t find it.

Depends on if you want a noise canceling type mic (probably unnecessary in the salon or nav station but useful on deck) and if your voice is unusually bass. Any of the electret condenser mics will work with the 802. Icon has a bunch of options to fit your wallet.
Having said that, it’s likely you won’t notice any change as the stock HM 126/174 mics supplied with this radio are broad spectrum pickup designs. Unless you go with a desk mic or equalizer or a combination thereof, nothing noticeable is likely.

There is no compression circuit in the 802 and I doubt any shop technician has the ability to improve on what Icom design created with their vast expertise, trying to enhance audio characteristics will only result in a lighter wallet.

[GILow]

Originally Posted by S/V Illusion

D

There is no compression circuit in the 802...

Say what? There is a speech compressor, and it seems to be a constant source of grief.

But don't take my word for it... here's Icom themselves...

"The speech compressor, utilizing DSP, increases average talk power. "

from: https://www.icomamerica.com/en/produ...2/default.aspx

[GILow]

Originally Posted by a64pilot

I have often wondered why there is no better Mic available for the 802, an after market Mic, the factory mic just doesn’t impress me.
A bit like the factory speaker didn’t either, but there are better speakers available, I went with a clr speaker noise canceling and it’s much better than the factory one.

If there is a better after market mic, I can’t find it.

I have not used my 802 much, but in the few cases I have I get mostly favourable reports on my clarity.

I suspect at lot of the concern with the 802 comes from its over-sensitivity to signal feedback (Icom state that a SWR higher than 1.6 will trigger the clipping problem many experience, if the modifications have not been made), the fact that many radios have the speech compressor turned off (according to K44WJA) and then there is the problem of the crumbling mic cords (which I have personally experienced.)

In all my trawling of discussions about the radio I do not remember any particular negatives expressed about the mic, other than the crappy cord construction, but I concede I was not specifically looking for such reports.

[a64pilot]

I just know from my little amateur radio experience (I’m not a Ham) that it seems step one in putting together a good radio is get a better mic, often a powered mic.
The Clr speaker made a huge difference in my opinion for example, maybe a “better” mic would also?

[S/V Illusion]

Originally Posted by GILow

Say what? There is a speech compressor, and it seems to be a constant source of grief.

But don't take my word for it... here's Icom themselves...

"The speech compressor, utilizing DSP, increases average talk power. "

from: https://www.icomamerica.com/en/produ...2/default.aspx

The confusion lies in terminology. Some seem to confuse DSP with compression. Two very different things. Apparently, the way Icom chose to describe DSP adds to the confusion. Regardless, neither would cause the problem described in the original post.

[Redline452]

Originally Posted by S/V Illusion

Not that it’s important but it’s deviation, not modulation, on an FM signal which determines voice quality. While it’s possible something has caused the deviation to change

Correct, it's not important: The "802 SSB" is a Single-Side-Band radio, not FM. SSB is a form of AM, with the carrier and one sideband removed, leaving a ... single.. sideband.

[Brian.D]

Don't forget the "suppressed carrier." Or, is that now old school terminology?

[Redline452]

... depends how much of the carrier you got rid of... some implementations leave a bit for receiver synchronization, some just don't filter it all out, some pretty much cancel it all out (and surely some new DSP FFT implementation just creates the desired sideband waveform ad nothing else). Still, not really germane to the OP's question.



Norm
VE2BQS
S/V Redline