Hand held vhf

[paddywackcocker]

Got two xm hand held vhf,s. Now I know there only cheep jobys but both have picked up an identicle fault. When useing on 80 (simplex or duplex , carnt remember wich way round) I can hear what every body is saying to the marina but not what the marina is saying to me, only get the marina on the fixed radio. Now I could live with one set having this prob coz its quite good to hear the other peeps but not so good when your on the helm comeing in and wont to contact from the cockpit. Anybody ever comeacross this Any experts out there think it would be a cheep repair or should I just go out and get a new one

 

[TheBoatman]

I'm no techie when it comes to radio but what you describe happens to a lot of radios on Ch 80.
I was testing a couple of new Standard Horizons h/helds the other day ~ talking to our local marina Ch 80.
I spoke they answered ~ mate speaks on a different set ~ they answer him but (me 10' way) can't hear the reply. I speak again they answer, he can't hear - strange!!!!

No doubt some brighter person than me will give a reason, but I wouldn't be to quick to change them yet.

Peter.

BTW
Those SH radios are some piece of kit ~ v.good for the price.

 

[VicS]

Hi Patrick,

A similar problem was posted on here a few weeks ago. The problem was caused because the set had been switched over to the US channel frequencies.

I forget all the exact details now but at the time someone quoted the transmit and recieve frequencies for the USA.

If I were you I would check to see if that is the trouble with yours. You may have to read the insruction book to find out how to switch them over!

 

[lenseman]

[ QUOTE ]
I spoke they answered ~ mate speaks on a different set ~ they answer him but (me 10' way) can't hear the reply. I speak again they answer, he can't hear - strange!!!!

[/ QUOTE ]

I think that the problem you describe might be due to 'Front-End Overload' of the receiver stage or the Automatic Gain Control (AGC) is very slow acting and because it is 'seeing' a very strong local signal (the other hand-held ten feet away), it 'shuts down' the receiver front end stages and they are not then able to hear a distant weaker station (ie - the Coast-guards reply)

 

[Amphitrite]

The reason IMO that some marine channels (incl. CH 80 I think) were changed from duplex to simplex a few years back to give room for the two AIS frequencies. I had my Simrad HT 50 reprogrammed for free by the distributor at the time...

 

[paddywackcocker]

cheers for replys, will start with the us bit, I do remember there was something in the manual about that. They havent been used close to each other or the fixed set .If all else fails will pop them in for the reprogram merlarky

 

[jfkal]

I had that with my ICOM handheld. Returned it for service and they changed a few capacitors in the receiver which had gone bad (marine environment?!). Worked again ever since. Get it checked out.

 

[Channel Ribs]

[ QUOTE ]
I spoke they answered ~ mate speaks on a different set ~ they answer him but (me 10' way) can't hear the reply. I speak again they answer, he can't hear - strange!!!!

[/ QUOTE ]

You can't talk to other boats on Ch80, it uses different send and recieve frequencies. The marina staff use them with the frequencies the 'wrong' way round so they can hear us.

 

[VicS]

Since yesterday evening I have checked on the technical stuff. In the UK Ch 80 is a duplex channel. The ship transmits on 157.025 MHz and the Shore station (Marina) on 161.625. In the USA it is a Simplex channel (both stations using 157.025). Hence if you have the US frequecies selected you can hear other ships but not the Marina.

Once correctly set you will hear the Marina but not the other ships. Thats a pita, it would be much better if we had it as a simplex channel as well as the yanks, but we dont.

 

[johnalison]

I sometimes set my Icom so that I can toggle between the two; occasionally useful if travelling with mates who call the marina before you.

 

[VicS]

[ QUOTE ]
occasionally useful if travelling with mates who call the marina before you.

[/ QUOTE ] More or less what I had in mind when I said I thought it was a pita that it was a duplex channel. You cannot hear if someone else is talking to the marina. You should of course listen for a while before calling then you will hear the marina at some point but who's sufficiently patient to listen for long enough? Practically nobody around the Solent! If it was simplex you would hear both ships and marina.

The old coast radio stations usually switched both together so that you could hear both sides of a call but the marinas may not have that capability.

 

[paddywackcocker]

Yep nice one Vic, put me classes on and read the book, guess what, there is a setting for us and it was on. Havent got a clue who could have fiddled with it seeing Im the only fat fingered owff that gets hold of em. Still I might leave one on just to be nosey.
Cheers again,
Pat

 

[andygreen84]

i agree, much less confusion using the american system but its nice to be different.