Ron said, "...the burden is on the inverter manufacturer to eliminate its RF interference" Ron, While it is probably true that the inverter manufacturer should eliminate the RF, if you reread Bill's original post, he was able to operate other VHF's from the same location and antennas. ICOM needs to figure out how to operate in the real world. If they are going to sell radios to the consumer marketplace, that don't require a professional installer then they should design and build a radio that is appropriate...just like the other guys do. Regards, Randy Pickelmann MORNING STAR lying in Clearwater, FL www.morningstar.talkspot.com

Some years back Motorola brought out a new line of land mobile radios that somehow got all the way through design, testing and manufacturing with having virtually no line noise filtering. When these units were installed in a vehicle, any little bit of alternator, heater motor etc noise that was present on the battery line was passed directly to the audio circuits and came out of the speaker amplified. When Motorola was advised of the problem, like ICOM, they said it was the installers fault and definitely not theirs. A month or so of fighting finally got them to admit their error and supply field modification kits to externally add the forgotten filters. Many of todays marine radios do not have very much filtering in the power input leads however due to the design of modern integrated circuit audio amplifiers they are less susceptible to this power line noise. It has been my experience that a great many boat electrical systems have some degree of noise on the power lines and can definitely be aided by the addition of a noise filter in the line before the more sensitive devices such as radios and sounders. This noise can come from the alternator, windscreen wipers and water pumps to name just a few. Drop into any electronics store that sells automotive stereo systems and for a few bux you can get a high amperage capable filter that will take care of all your electronics equipment. YMMV John Tones MV Penta Sidney, BC

John, can you be a little more specific about type (maybe even brand/model) of filter, and how and where it would be installed in the system? My electrical knowledge is zero, so an explanation for dummies would be very much appreciated! I have an ICOM at the lower steering station with a Ram mike up on the flybridge. No noise on the lower unit, but you can definitely hear noise on the Ram mike (it changes pitch with the engine speed). Thanks, Ted Hugger Sequin, GB32-126 Cape Elizabeth, ME > -----Original Message----- > From: trawlers-and-trawlering-bounces@lists.samurai.com > [mailto:trawlers-and-trawlering-bounces@lists.samurai.com] On > Behalf Of John Tones > Sent: Tuesday, July 22, 2008 12:19 PM > Cc: trawlers-and-trawlering@lists.samurai.com > Subject: T&T: Icom - bad support > > Some years back Motorola brought out a new line of land > mobile radios that somehow got all the way through design, > testing and manufacturing with having virtually no line noise > filtering. When these units were installed in a vehicle, any > little bit of alternator, heater motor etc noise that was > present on the battery line was passed directly to the audio > circuits and came out of the speaker amplified. > When Motorola was advised of the problem, like ICOM, they > said it was the installers fault and definitely not theirs. A > month or so of fighting finally got them to admit their error > and supply field modification kits to externally add the > forgotten filters. > Many of todays marine radios do not have very much filtering > in the power input leads however due to the design of modern > integrated circuit audio amplifiers they are less susceptible > to this power line noise. > It has been my experience that a great many boat electrical > systems have some degree of noise on the power lines and can > definitely be aided by the addition of a noise filter in the > line before the more sensitive devices such as radios and > sounders. This noise can come from the alternator, windscreen > wipers and water pumps to name just a few. > Drop into any electronics store that sells automotive stereo > systems and for a few bux you can get a high amperage capable > filter that will take care of all your electronics equipment. > YMMV > John Tones MV Penta > Sidney, BC > _______________________________________________ > http://lists.samurai.com/mailman/listinfo/trawlers-and-trawlering > > To unsubscribe or modify your subscription options (get > password, change email address, etc) go to: > http://lists.samurai.com/mailman/options/trawlers-and-trawlering > > Trawlers & Trawlering and T&T are trademarks of Water World > Productions. Unauthorized use is prohibited.

Ted Hugger wrote: > John, can you be a little more specific about type (maybe even brand/model) > of filter, and how and where it would be installed in the system? Reply - I am not certain of what exact makes / models of filters are available in the US but the ones I have used for years are produced by Magnadyne in Quebec. They are rated at 20 amps and are essentially produced for the auto stereo market. The filter has three or sometimes four leads, depending on the manufacturer, two of which are the "hot" in and out power and the rest ground. It would be installed in the power feed to the radio, with the radio power lead cut and run through the filter and the ground lead (s) from the filter connected to a good ground. On my boat the filter is by the breaker panel with all the electronics, except the auto-pilot and radar, fed thru the filter. In my case an un-fused lead (except for the main breaker) is run off the main positive buss and then the output of the filter is connected to the appropriate breakers. If you do not already have a good ground connection at the radio location it would be a good idea to install one if at all possible. It should be considerably larger in size than the usual power leads supplied with a radio and should run as direct as possible to the main ground point on your boat. I am certain that if you were to drop into any better car stereo installation shop they would have such a device in stock as power lead noise is not an unusual situation. Let me know if you have any more questions and good luck John Tones MV Penta Sidney, BC