Icom M802 ADSP - add on noise reduction device

[chouliha]

We are into our 13th year with our Icom M802 and previous to that had 2 Yaesu HAM radios.

Just curious if any of you are using a ADSP (Audi Digital Signal Processing) device that is suppose to help with background noise and static.
Noise Canceling Speakers

With the Yaesu there were a number of filters that could be adjusted to lower the noise and improve the hearing. The 802 has very limited filters available

We are heavy SSB/HAM users and are aware of all the various devices on board that can cause interference. But even though everything is turned off the noise is very high compared to other radios we have owned or radios we recently have used on other boats to run nets. The noise at times makes it very hard to hear people trying to check in. We sent the ICOM M802 back to be bench tested about 10 years ago and ICOM NA said everything is within specs.

Any actual users of the ADSP devices - would appreciate your comments

Thank you and safe sailing

Chuck
Jacaranda
Mo'orea, French Polynesia

[SoonerSailor]

Audio DSP devices can improve the intelligibility of weak SSB signals somewhat, but definitely not a cure-all. If it allows you to adjust low and high frequency cuts, you may be able to tailor the sound better to your ear.

[alctel]

https://www.bhi-ltd.com/noise-cancel...ers/dspkr.html

This one has a ton of good reviews from mobile hams. I'll probably pick it up one day

[chouliha]

Its also been suggested by some Hamsters to look at Clr speech speakers.

West Mountain Radio - CLRspkr ClearSpeech® DSP Noise Reduction Speaker

Any one used one of these speakers?

Thank You

Chuck

[Gypsyjon]

You probably already know this, but just in case, be sure all LED lights are turned off.
Jon
KM4UJP

[TLSparks]

I use a CLRSpeach DSP speaker. It helps a lot. However, I am curious about your noise. With everything turned off, how many signal bars are shown on the M802 display?

One common installation error is connecting the M802 to the breaker panel instead of the battery directly. The battery is a giant filter as it likes DC and squashes noise signals.

Do you have a long run to the battery or are you using the supplied cable from Icom. If so, twisting the cable will help eliminate noise coming in through the power supply. I also recommend a mix 31 ferrite core at the back of the transceiver on the power supply line. If you use one built for RG8, you should be able to loop the DC wire at least 2 times through the snap on core. Make your loops equal and tight will result in the effect of having 4 single cores on the line.

If your noise is coming in through the antenna and everything is off, it is what it is. I would check for something that may be on all the time or possibly a ground loop. Your 12VDC should come to the radio. The ground on the control cable should be attached to the ground lug on the transceiver. The ground wire on the tuner end should be cut off and not connected. The only thing coming off the tuner lug should be your RF ground. The RF ground should not be connected to anything that is also connected to the -12V side of the battery e.g. engine, bonding etc.

Here is a link to a document I put together to help cruisers make sure they have a good installation: http://www.made-simplefor-cruisers.c...e%20M802-1.pdf

I hope that helps.