Icom 402 radio woes..or is it my antenna system?
 

x-no-archive:yes

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

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.

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

Icom 402 radio woes..or is it my antenna system?
 

On 20 Aug 2003 09:31:53 -0700, (John) wrote:

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.

A 3db antenna is always used on sailboats, precisely because it
tolerates heel. With a 3db 56 feet off the water, he should have 20
miles range easily.



Rodney Myrvaagnes J36 Gjo/a


MOM CASTS TOT IN CEMENT

Most experts voice cautious optimism

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...

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/

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.

Icom 402 radio woes..or is it my antenna system?
 

Add me to the list of ICOM 402 users with the same mike problem...main
mike is weak/distorted, but command mike works fine. I've asked ICOM
USA about it, and will share their response.


(Kevin) wrote in message . com...
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!

Icom 402 radio woes..or is it my antenna system?