Get the Voice Compression turned back ON in your Marine SSB Transceiver - Icom IC-M802

* Alans Note, Edit 03-13-2010 - I’ve been reading up on the causes of “splatter” (IMD - Intermodulation Distortion), etc. in regards to Ham Radio (Amateur Radio) in order to do my best to put out a clean signal from my own HF Tranceiver (Kenwood TS-480). I have heard a lot of “splatter” and “bleed over” of other amateur radio operators on the Ham Bands while monitoring and/or communicating with these other stations. Often it makes it almost impossible to hear the station that you are listening too, and that makes it impossible to communicate.

Now the FCC rules and regulations for Marine SSB Radio and Amateur (Ham) Radio are different. Amateur Radio Operators are responsible for their own equipment and how it operates and have much more flexibility. Marine SSB Radio Operators - although they must comply with FCC and International Rules - do not have the level of access to modify and control their equipment. So the FCC Type Acceptance process is responsible for compliance with standards of radio emissions. Supposedly when Icom submitted the IC-M802 SSB Radio for FCC Type Acceptance they had the Speech Compression “Off”. So turning the Speech Compression back “On” for use in Marine SSB Radio (as opposed to Amateur Radio SSB Radio) Communications is *NOT* recommended by myself. The only exception I can garner to this is *if* you, the Marine SSB Radio Operator, are also an Amateur Radio Operator, and *you* know what you are doing. In which case *you* are solely responsible for the operations on both Amateur Radio and Marine SSB Radio, when using your Icom IC-M802 Radio.

The following link contains the following quote, as well as more information about this. http://forum.ssca.org/phpBB3/viewtopic.php?f=5&t=4791&start=30

There is a good reason to operate a marine radio with compression _off_, and it has nothing to do with spectral purity or occupied bandwidth.

Remember:

___Compression raises the level of soft sounds.___

The noise level on a boat with its engine running is _high_. I found that if I turned compression ON (with my IC-706), background engine noise would be boosted to about 10 watts output (on a 100-watt max transceiver) when I keyed the mic.

My speech became hard for others to understand, because of the roar between syllables.

With compression OFF, everything was fine — the engine was audible in the background, but was not obtrusive.

So, think hard before you (whomever you are) decide that you want to set your IC-802 to use its compressor.

Charles / “Right Galah” / VA7CPC

PS — I am not suggesting that Icom was “right” when it put the On/Off control into the hands of the dealer / installer, rather than the mariner. But their decision might have some logic behind it.

In closing this update, Alan Spicer says - So in light of this new information, this 03-13-2010 update, please keep the above recommendations in mind as you read the following previous article posting by me. In a potentially very noise environment onboard a marine vessel - it might not be a good idea to have the Compression “ON” on your Icom IC-M802 SSB Radio. I have the same problem here on a Kenwood TS-480 Ham Tranceiver … I have a very good (studio quality, Heil HM-10 Dual) external microphone. If not properly adjusted - and if I’m not paying attention to my ambient background noises - it’s very possible for me to broadcast a cats meow, a dogs bark, the tv in the living room, and with the back window open the kids playing the house behind me. Soooo. If your not a responsible ham radio operator, operating on marine ssb frequencies or ham frequencies, then possibly you should NOT have the compression turned back on in your IC-M802 Radio. But whatever the case may be…. Your mileage may vary… I won’t be responsible, by the writing of an article, for what you do on the airwaves.

Icom IC-M802 Marine SSB Radio

Icom AG-140 Antenna Tuner

http://www.latitude38.com/features/SSB.html 

I’ve got two final tips.

First, if you sent your Icom 802 to the factory to get the ‘clipping’ problem fixed, you’ll note that there are two places to plug in the antenna. One is for the DSC antenna, the other for your SSB antenna. Unfortunately, they are not clearly labeled. A number of people have gotten their radios back and plugged their SSB antenna into the wrong port. As a result, transmit and receive range are minimal. You would see an antenna tuner error if plugged into the wrong jack. Set it up temporarily and test it with time signals.

Second, Icom is very conservative in an attempt to make sure none of their radios violate FCC rules on output power and how wide the signals are. I think they are too conversative. If you get that voice compression software unlocked, your radio transmissions will boom out with a commanding signal like Voice of America. The software upload is only available from authorized Icom dealers. They can come aboard and plug it into your radio, as well as the most recent ‘user channel’ update. It usually takes just 15 minutes.

- gordon west

* I noticed this on a yacht in Fort Lauderdale. I called Icom Tech Support about several things … and they basically told me the same thing … in order to make sure that you don’t go out of FCC or International Marine SSB rules and/or regulations … Icom has the Speech Compression (aka Speech Processor) turned OFF by default in IC-M802 Marine SSB radios. An Icom Dealer (or anyone else with the right “clone” programming software and computer-to-radio cable) can turn that back on.

* Let me see… let’s take a nice SSB radio and cut its shoes off. Might as well have the main RF power amplifier disabled as well. Of course Icom Tech Support says they can get decent power out of the radio by whistling into the microphone. I’m sure that’s what we all do … we whistle into the microphone when communicating. You could probably whistle out your message in Morse Code … either that or get the Compression turned back ON.

Of course once you’ve done that you no longer have to scream into the microphone. Just talk in a normal voice from about 1/2 a foot to 1 foot away and sort of on an angle “across” the front of the microphone. That will likely keep you from overmodulating and possibly getting into trouble for being out of technical specifications.

CS-M802 seems to be the Cloning or Programming software for the IC-M802.

Cloning cables and software

 http://www.theantennafarm.com/catalog/index.php?main_page=index&cPath=75_76_820_901_915

The software, the cable, even a USB version of the programming cable…

http://www.eham.net/reviews/detail/6205 says… 

I use the CS-802 software to customise the 160 User programmable channels.
Also used the same software to turn on the Compresion which increased the power during voice/mic use.
Brought up the average output from around 60-70W to 100 and up.
 

The SCS PTCII-Usb Pactor Modem - used for Sailmail

—

Alan Spicer Telecom / Alan Spicer Marine Telecom

http://www.marinetelecom.net - http://www.wifiyacht.net

communications (at) marinetelecom.net

+1 954 683 3426

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