Any one good with VHFs? Won't transmit on high

adamdavi3s · 08 June 2009, 19:37

Hi Guys,

I will add to this as required, only really just thought about putting it up here!

My VHF works a treat on low, will transmit and receive fine.

However, flick it to high... it still receives ok but when you try and transmit, it 'flashes' in that it seems like it can get power for a second, then drops, then gets power, then it drops.. when it drops it doesn't go off, it just goes off transmit and back to static. I thought it was an iffy connection in the mic transmit button but it works fine on low...

To high power drain?

geoffs · 08 June 2009, 20:09

Bad power connection/low battery

Nos4r2 · 09 June 2009, 00:15

Quote:

Originally Posted by geoffs

Bad power connection/low battery

Yep. Had the same problem last year and it was a corroded fuse.

al40 · 09 June 2009, 23:31

or wires that are too thin at some point in the circuit - have seen this a few times. If you have an inline switch this is also a common culprit.

Jon Brooks · 10 June 2009, 08:33

I am with Geoff, have seen this loads of times over the years.
Check and clean all the terminals on the way to the battery and def check the battery end.

Cheers

adamdavi3s · 10 June 2009, 21:04

Hmm yeah it is probably the switch. I'll try taking a feed straight from the battery and seeing if it plays ball!

Thanks for the advice!

Cookee · 12 June 2009, 09:16

Quote:

Originally Posted by adamdavi3s

Hmm yeah it is probably the switch. I'll try taking a feed straight from the battery and seeing if it plays ball!

Thanks for the advice!

Bring it up to Churchstow and I'll have a look if you still have problems - 07836 268747

wavelength · 12 June 2009, 14:53

ok this is probably a complete red herring but.....
our icom wouldnt transmit on hi, always went straight down to lo when the PTT switch was pressed. It went in to local guy to have a look at and no fault was found (couldnt send it to Icom as the set had come back from the states with us - tut tut!). In the end and at the local guy's suggestion we changed the co-ax (orrible cheap stuff with an outer wrap of bum fluff) which was routed very close by the set, & never had another problem with it. So it might be worthwhile trying a different route for the co-ax just to try it. OK the electronic whizz kids may say its cobblers -but it worked for me

.

chris123 · 12 June 2009, 18:32

Quote:

Originally Posted by wavelength

OK the electronic whizz kids may say its cobblers -but it worked for me

.

I don't think it is cobblers at all - I was going to say something similar - some VHFs drop the power down if they do not see the correct aerial load.

Cheers

Chris

al40 · 13 June 2009, 00:06

Quote:

Originally Posted by chris123

I don't think it is cobblers at all - I was going to say something similar - some VHFs drop the power down if they do not see the correct aerial load.

Cheers

Chris

That's a neat feature - saves the set getting fried!

wavelength · 13 June 2009, 09:41

I dont think it was any clever feature-just a case signal radiating thru the cabling and knocking the set back to lo somehow-anyway like I said it worked. As for frying the set by transmitting with no aerial -yes it is something we mention on radio courses as a possible result, but it is not a foregone conclusion that it will happen, years ago we held conversations with other angling boats in our group at short range, but on hi power (naughty), all day. It was only that evening that one of the crew noticed a dangling co-ax wire behind the radio

................... and of course we all blamed each other

.