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Icom 402 radio woes..or is it my antenna system?
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Is the radio getting enough power? A lot of times when we have various kinds of radio or electronics trouble it's because of inadequate wiring from the battery to the radio. "J. Slater" wrote: Ok. I'm on my 3rd new Icom 402 VHF radio. The first one was exchanged for extremely poor microphone performance when transmitting with the main unit mic (as opposed to the Command Mic). You would have to YELL nearly at the top of your lungs in order for the volume output picked up by all sorts of VHF's, fixed mounts and handhelds, at all different distances and power outputs, BUT with the optional command mic, you could talk in a normal tone and volume and there was no problem! Second unit was a demo unit, and had a slightly better mic performance, although not near as good as the original "old" Icom m45 that was in the boat when purchased. The problem with this radio is that it was having trouble recieving from some radios, near and far. It was picking up Garmin Handhelds (models 720 and 725) perfectly yet would not recieve any kind of transmissions from a couple Hummingbird models, handhelds as well as fixed mounts. At the same time, my Garmin 725 was picking up the transmissions from these same Hummingbirds, whilst the Icom was not. Of course it has to be a problem with my antenna, me thinks. What are the odds of having 2 factory new Icoms screwy? Going step by step with Nigel Calders book, I test my antenna connections at the radio, all good, climb my mast and inspect the antenna connections and antenna up top, all "looks" good, the coax insulation is in great shape, the heat shrink is all intact and tight, the antenna itself appears as new as when I picked up the vessel three years prior... I didn't remove the connection at the antenna and do a continuity or ohm test... but I'm not convinced that my antenna is the problem, especially when the original Icoms had no problems recieving or transmitting (just the mic fault on the first 402). Ok, have I thoroughly lost everyone yet? The third unit sounds great (voice quality and volume are terrific on all radios) except that it appears that I can't reach anybody past 5 miles out, line of sight on the water! Batteries showing 13.6 volts (all were replaced 6 months ago, with new cables, etc.). Radio is connected "directly" to house battery bank and my voltmeter confirms a full 13.6 volts reaching radio. Yes, I'm also sure the radio is on "High" power output. I'm also having trouble picking up transmissions outside of 5 miles as well. Seems to point towards the antenna again, doesn't it? Antenna height is 58 feet from the water and it is a 3db model if my memory serves me right. Is there something obvious that I'm missing here? I just don't really want to climb my mast anymore times than I have to... Perplexed Boater. J. grandma Rosalie |
#2
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Icom 402 radio woes..or is it my antenna system?
"J. Slater" wrote in message ...
Ok. I'm on my 3rd new Icom 402 VHF radio. The first one was exchanged for extremely poor microphone performance when transmitting with the main unit mic (as opposed to the Command Mic). You would have to YELL nearly at the top of your lungs in order for the volume output picked up by all sorts of VHF's, fixed mounts and handhelds, at all different distances and power outputs, BUT with the optional command mic, you could talk in a normal tone and volume and there was no problem! Second unit was a demo unit, and had a slightly better mic performance, although not near as good as the original "old" Icom m45 that was in the boat when purchased. The problem with this radio is that it was having trouble recieving from some radios, near and far. It was picking up Garmin Handhelds (models 720 and 725) perfectly yet would not recieve any kind of transmissions from a couple Hummingbird models, handhelds as well as fixed mounts. At the same time, my Garmin 725 was picking up the transmissions from these same Hummingbirds, whilst the Icom was not. Of course it has to be a problem with my antenna, me thinks. What are the odds of having 2 factory new Icoms screwy? Going step by step with Nigel Calders book, I test my antenna connections at the radio, all good, climb my mast and inspect the antenna connections and antenna up top, all "looks" good, the coax insulation is in great shape, the heat shrink is all intact and tight, the antenna itself appears as new as when I picked up the vessel three years prior... I didn't remove the connection at the antenna and do a continuity or ohm test... but I'm not convinced that my antenna is the problem, especially when the original Icoms had no problems recieving or transmitting (just the mic fault on the first 402). Ok, have I thoroughly lost everyone yet? The third unit sounds great (voice quality and volume are terrific on all radios) except that it appears that I can't reach anybody past 5 miles out, line of sight on the water! Batteries showing 13.6 volts (all were replaced 6 months ago, with new cables, etc.). Radio is connected "directly" to house battery bank and my voltmeter confirms a full 13.6 volts reaching radio. Yes, I'm also sure the radio is on "High" power output. I'm also having trouble picking up transmissions outside of 5 miles as well. Seems to point towards the antenna again, doesn't it? Antenna height is 58 feet from the water and it is a 3db model if my memory serves me right. Is there something obvious that I'm missing here? I just don't really want to climb my mast anymore times than I have to... Perplexed Boater. J. Sounds like the antenna is bad. Is this a sail boat? A 3 db antenna isn't giving you much gain at all. Is the problem while under sail with the boat healed over? Sail boats have problems while under sail with radio's. |
#3
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Icom 402 radio woes..or is it my antenna system?
On Wed, 20 Aug 2003 04:52:48 GMT, "J. Slater"
wrote: Ok, have I thoroughly lost everyone yet? The third unit sounds great (voice quality and volume are terrific on all radios) except that it appears that I can't reach anybody past 5 miles out, line of sight on the water! Batteries showing 13.6 volts (all were replaced 6 months ago, with new cables, etc.). Radio is connected "directly" to house battery bank and my voltmeter confirms a full 13.6 volts reaching radio. Yes, I'm also sure the radio is on "High" power output. I'm also having trouble picking up transmissions outside of 5 miles as well. Seems to point towards the antenna again, doesn't it? Antenna height is 58 feet from the water and it is a 3db model if my memory serves me right. Is there something obvious that I'm missing here? I just don't really want to climb my mast anymore times than I have to... Try borrowing a known good radio from a neighbor. You can eliminate the antenna variable that way without climbing. Or, get an emergency antenna and see if your radio works better with that. You probably ought to carry one anyway. Also, it may be an adapter is available to couple your handheld VHF to the boat's antenna cable. If the 5-W radio gets more range than the Icom's 25, you know the answer. Rodney Myrvaagnes J36 Gjo/a MOM CASTS TOT IN CEMENT Most experts voice cautious optimism |
#4
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Icom 402 radio woes..or is it my antenna system?
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#5
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Icom 402 radio woes..or is it my antenna system?
I wonder if your mic is now "submersible" with the membrane compromised? It
is interesting that it made that much of a difference though... |
#6
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Icom 402 radio woes..or is it my antenna system?
J. Slater wrote:
The third unit sounds great (voice quality and volume are terrific on all radios) except that it appears that I can't reach anybody past 5 miles out, line of sight on the water! Batteries showing 13.6 volts snipI'm also having trouble picking up transmissions outside of 5 miles as well. Seems to point towards the antenna again, doesn't it? Antenna height is 58 feet from the water and it is a 3db model if my memory serves me right. If the antenna is fiberglass and over about 3-5 years old, it may be trashed. Ours looked fine, but when I replaced it with a stainless steel 3db with epoxied coil, recommended by Practical Sailor at the time, our range improved considerably: spotty 2-mile range to a fairly consistant 25nm on a quiet channel. Also, if you're using standard "CB" coax, switching to RG-8X (I believe) cuts down loss. -- Jere Lull Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD) Xan's Pages: http://members.dca.net/jerelull/X-Main.html Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/ |
#7
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Icom 402 radio woes..or is it my antenna system?
I have the exact same problem! Excellent transmit volume on the
Command Mic, very quiet on the main unit. Excellent transmit distance on both units. Receive works very well on both as well....Didn't discover problem until down in Bahamas, now I doubt they'll replace the main unit a year and half later. "J. Slater" wrote in message ... Ok. I'm on my 3rd new Icom 402 VHF radio. The first one was exchanged for extremely poor microphone performance when transmitting with the main unit mic (as opposed to the Command Mic). You would have to YELL nearly at the top of your lungs in order for the volume output picked up by all sorts of VHF's, fixed mounts and handhelds, at all different distances and power outputs, BUT with the optional command mic, you could talk in a normal tone and volume and there was no problem! Second unit was a demo unit, and had a slightly better mic performance, although not near as good as the original "old" Icom m45 that was in the boat when purchased. The problem with this radio is that it was having trouble recieving from some radios, near and far. It was picking up Garmin Handhelds (models 720 and 725) perfectly yet would not recieve any kind of transmissions from a couple Hummingbird models, handhelds as well as fixed mounts. At the same time, my Garmin 725 was picking up the transmissions from these same Hummingbirds, whilst the Icom was not. Of course it has to be a problem with my antenna, me thinks. What are the odds of having 2 factory new Icoms screwy? Going step by step with Nigel Calders book, I test my antenna connections at the radio, all good, climb my mast and inspect the antenna connections and antenna up top, all "looks" good, the coax insulation is in great shape, the heat shrink is all intact and tight, the antenna itself appears as new as when I picked up the vessel three years prior... I didn't remove the connection at the antenna and do a continuity or ohm test... but I'm not convinced that my antenna is the problem, especially when the original Icoms had no problems recieving or transmitting (just the mic fault on the first 402). Ok, have I thoroughly lost everyone yet? The third unit sounds great (voice quality and volume are terrific on all radios) except that it appears that I can't reach anybody past 5 miles out, line of sight on the water! Batteries showing 13.6 volts (all were replaced 6 months ago, with new cables, etc.). Radio is connected "directly" to house battery bank and my voltmeter confirms a full 13.6 volts reaching radio. Yes, I'm also sure the radio is on "High" power output. I'm also having trouble picking up transmissions outside of 5 miles as well. Seems to point towards the antenna again, doesn't it? Antenna height is 58 feet from the water and it is a 3db model if my memory serves me right. Is there something obvious that I'm missing here? I just don't really want to climb my mast anymore times than I have to... Perplexed Boater. J. |
#9
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Icom 402 radio woes..or is it my antenna system?
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