Icom VHF - hiccup??

[David_J]

We have an Icom IC-M601 installed. Coming up to three years old.
Moored in Haslar for a few nights last month and the radio develops a permenant hiss, like the squelch control just isnt working. But on receiving a strong incoming signal the hiss goes but returns at the end of the transmission.
Tried switching on and off a few times (like with the PC!!!) disconnecting the command mike (remote) disconnecting shore power, checked aerial connections etc etc. A hand held Icom was working just fine through all this so I guess it has to be something about the fixed installation. It was like that for two days.
When we left to run up to Port Solent, all back to normal, no hiss and squelch working as normal. Hiss never came back!!
It did exactly the same overnight in Moody's a few years ago. When we went down river all went back to normal...... any bright ideas????

 

[brianrunyard]

What was the state of charge of the battery? I've had this happen due to battery getting low, as soon as I started the engine and put some charge back into the battery all was well.

Regards,
Brian

 

[oceanfroggie]

I've had a similar intermittant problem the IC-503 and the remote command mike. Once I plugged the command mike extension lead out of the back of the 503, problem solved. The command mike extension leads were long and getting interferrance from other appliances on the long run to the flybridge. In our case the fridge was the culprit when ever the motor kicked in. I was advised to re-route the cable away from noise sources (not easy to do in our case).

Generally I love the ICOM software, and especially their implementation of dual watch, tri-watch and priority scan, which is great when leading a CIC and you need to keep an eye on 16, a local port traffic, and the CIC working channel (6,8 or 72). Other manufacturers DW just slice the time irrespective of the existance of a carrier (eg Silva). ICOM is the Mercedes of VHF - simply the best.

 

[David_J]

Re: Icom VHF - hiccup??

Batteries were full as full. We had been on shore power for a few days in Brighton, then three hours or so running down to Gosport and a couple of days on shore power there. Dont think it was battery power but well worth keeping any eye on.

 

[David_J]

Re: Icom VHF - hiccup??

I think the Icom equipment is really good, in spite of this problem. I am not so sure about interference in our case because whilst we only have a few hundered engine hours we do spend a lot of time on board and this problem has only come along two times in nearly three years.
First time was a worry but then it never came back,,,,, untill now, two years after the first problem!!! I guess I will just wait and see if it happens again before ripping the boat apart.
Might have a word with Mr Icom at the show.

 

[DAKA]

Re: Icom VHF - hiccup??

could it be a handheld with PTT switch jammed on a boat nearby ?

People tend to wedge their handheld into any space and the PTT switch offers an ideal temporary holder.

Next time it plays up try changing channels if not already done, your own hand held was maybe too far away to pick up the PTT depressed unit.

 

[Nauti Fox]

Send a PM to Jon Brooks, he works for them and is always helpful.

 

[JonBrooks]

Hi Dave

This is an odd one as it happens so few times.
If it was happening all the time it would lead me to think radio or as already stated coming from another source on the vessel.

All of the abve comments would be exactly my train of thought as well, batteries etc.

I will be at SIBS I can be found on the S M Group Stand (G098) please feel free to come say hi but am not sure I will be of any further help

I am more than happy to have the guys here give the set a once over for you FOC.
If you send it back put a covering note explaing you symptons and that info in this thread.

Oh and thank you to the others for the great comments.

Best regards

 

[David_J]

Re: Icom VHF - hiccup??

Jon

Many thanks for your comments and kind offer but I think I will hang on to see if it does it again and if it does, I will take some time for a really thorough check through all the suggestions on here.
A few days of downtime in three years and only when moored is strange but certainly disaster. Never a hitch when out and about doing the real boating stuff.
Fantastic equipment. I have the IC-M1Euro handheld.. good performance and batteries last forever!!

 

[redglow]

Re: Icom VHF - hiccup??

David,

Have had the same problem with an Icom, but that was when the alternator belt had snapped and we were returning to the marina (6 hour trip). The battery volts dropped quite quickly and the radio displayed the same symptoms as you describe, once some charge was restored the radio worked fine. If I were a betting man I would definitely put my money on the battery, especially as it has only happened when moored up and radio returned to normal as soon as you put some charge into the battery.

Kev

 

[David_J]

Re: Icom VHF - hiccup??

Kev
Many thanks. Thats the top of my list now. Must do some checking up on the circuits. I have not traced how the VHF is connected in!! which batteries etc

 

[Kawasaki]

Re: Icom VHF - hiccup??

I have a 25 year old Icom IC-180, inherited with My boat.
Lovely piece of kit.
Disconnected the shore power 2 day,s ago, suffering severe anode wastage at the moment. The disconnection was prompted by another thread on here which suggests shorepower connection could accelerate the problem.
However connected back up today and noticed the fridge compressor began to work very hard,fridge was not cold so I think My "domestic " batteries had been run down by the fridge.
The trusty Icom had been failing to transmit so I,ve changed the iffy looking fuse holder and cleaned up a few connections , seems OK now.
Low and behold a hiss arrived! Just as described!
The fridge has always "interfeird" with the VHF, in that a "squeek" can be heard through the set when the fridge "kicks in" but has not affected transmission or reception to any degree.
Whilst delivering an Aquastar a couple of years ago I found out on that particular boat I could not transmit at all with the fridge swiched on! Warm beers at the end of that trip!
These experiences seem to coincide with earlier posts.

"Listening Forum--Out" /forums/images/graemlins/smirk.gif

 

[oceanfroggie]

Re: Icom VHF - hiccup??

[ QUOTE ]
The battery volts dropped quite quickly and the radio displayed the same symptoms as you describe,

[/ QUOTE ]Could just be a voltage drop over a long cable run, or a voltage drop over a faulty CB.

 

[ColinHuggins]

Re: Voltage drop??

I find that the first piece of kit to go down is the stereo, which surprises me. Do car radios need more than 12 volts?

 

[David_J]

Re: Icom VHF - hiccup??

Good stuff this. Thanks. Looking more and more like a low volts problem. Come to think of it I dont think I ran shore power the first night in Haslar. It never dawned on me that could hit the battery so hard and of course the engine started easy off the starting batteries. Surely the domestic batteries cant be getting tired in less than three years, or does the fridge really take that much wallop??
Easy test I suppose is just run the DC systems with fridge for a few days and see what happens. I will let you know what happens.
It seems on here that others have sufferred the same or similar so is it a characteristic of VHF radios or Icom in particular that the hiss comes with low volts. I must check the spec for the radio when I get to the boat to see what the volts range is on the supply then monitor what happens when I work the batteries a little. Fascinating, but I must get out more. Just a frustrated engineer I suppose.

 

[oldgit]

Re: Icom VHF - hiccup??

My domestics failed this summer almost exactly 4 years old,suspect always on fridge did for them.Still bit of life left and am keeping them as emergency back up for lighting etc.

 

[oceanfroggie]

Re: Icom VHF - hiccup??

We have a little mobitronics unit which allows our fridge to run off 220v when in the marina, and 12v when underway. It's switches automatically, and means we can disconnect the battery master and therefore leave the battery charge off when in the marina. Hence the 12 system is 100% idle 95% of the time.

 

[redglow]

Re: Icom VHF - hiccup??

David,

Further thoughts on domestic battery(ies). As they are being regularly charged, make sure electrolyte is topped up with distilled water. I thought mine were U/S after one season (batteries 3 years old) but then checked and found them with virtually no electrolyte in them. I topped them up - expecting them to be permanantly damaged but they recovered and now are working as good as new. I suspect the previous owner had not topped them up, so it is worth checking.

 

[Piers]

Re: Icom VHF - THE CURE

Hi David_J

I have had the exact same problem for the last three years. Sounds as if the squelch needs turning up but there was no further control available. Endless background hiss. The only way I used to resolve it was to switch to another channel and back again before it re-started.

Returning the set to ICOM found no errors, but the service manager did make a suggestion. Might it be interference?

THE HUNT BEGAN, and I found the source. Radar. I have a Simrad set with a 4' open scanner. With my radar not scanning, no intereference and the ICOM works 100% fine. With it scanning, a real (hissing) pain. Further testing confirmed the radar theory to me. In a marina, I asked the boat next door to start scanning - the problem returned as long as his radar was on. In the Solent, I motored close to some large ships (outside the normal 'exclusion' zone of course...) and on most, the problem returned.

SO? I fitted a ferrite core around the ICOM aerial cable an inch from where it connects to the set, and SUCCESS, it has virtually 100% solved the problem! Just down to trying different sized cores to attain 100% cure.

Do let us know the success.

 

[David_J]

Re: Icom VHF - hiccup??

Thanks for that.
I have to admit I have not checked the electrolyte levels for a while, now top of the list. I am also going to do a few crude checks on battery voltages against load over time.