Topic: Legal use of pmr radios

[Westie]

Quote (Mr Rizla @ Feb. 07 2008,08:56)

Am going to try and organise a meeting for anyone interested in Comms, especialy useful for USR stewards, anyone interested? send me a PM

No don't tell me, will it be at the Ace on a Friday night by any chance??   '>

[1_POB]

Mr.Rizla,

    I am just setting up an Autocom and related tat on my VFR VTEC ready for a tour over easter.
     I bought ALAN 441 PMR radios over the summer and had limited success with them over the last riding season. Essentially we (myself and two other riders) just had the radios in our pockets and we were using the standard headsets which precluded VOX operation (due to wind blast) so we used PTT which was a bit awkward on a sports bike. We have all therefore invested in Autocom systems to manage the PTT/Vox issue and now I've been looking at improving reception which was found to be poor over the summer.
    I have taken the radio apart and the rubber duck antennae is a "helical" coil about 2.5 inches long. I understand that the best performance on these wavelengths would be had from an aerial about 15cm long. Is that total length of the "Wire" or does that mean 15cm of coiled/helical wire? I also don't understand that most other aerials I've encountered on air band radios are bi-pole whereas this aerial appears to have a single contact within the radio. Any suggestions on what I can do to improve the range which appears to be about 600m with LOS or as low as 100m in town when one rider turns a corner.

Cheers,

Ed

[john]

yeah I'd be interested in this, I have two flavours of PMR radios, a few cheaper ones that only use the 8 main channels and some others that use the whole range of sub channels. I've found that the cheaper ones range is pretty hopeless but the full spec units can manage about 2km or more in fairly open environments especially on the road.

Now if the range could be extended on these with a bit of fiddling, given that they're pretty cheap in the first place, that would really be very useful '>

[TallGuy]

With regard to PMR radios. here is a test for you. Go to and open space with a mate and see how far away you can get and still communicate with the radios held in your hand. Now repeat the experiment with the radios in a belt pouch and using a remote mic (on VOX you can't touch the PTT button).  Is the range less?

If the range is less then the radio is using you as part of it's antenna and that is why when fitted on a bike or on a belt pouch it doesn't work so good.

As for aerial length, this is determined using transmission line formula and is a function of physical length, shape, impeadance and reactance. For those that has CB radios you will remember the VSWR meter and the tuning pots on the base of the antenna. That was all about matching the aerial to the installation.

[Spill]

I used to have CB on my XJ650.
One year a group (4) of us went up to Shetland all miked up. Great fun.
Had a PTT switch on the handlebar and a mike and speaker taped/glued in the helmet. The rig stowed in the tankbag and the twig was on the rear carrier, which was, I think, the last metal one I had.

[The Yeti]

I was thinking of getting on of these...

Bluetooth PMR

And stick it under the seat or in a tank bag.
Can't be doing with a load of wires attaching me to the bike.

[Grandma]

They look brilliant and not too expensive either, may be just what the USR's could use?

[Stu]

I went mad today and bought 2 complete autocom setups with bike to bike radios as well '>

I looked into all the other types of headset and radios and kept coming up against the same thing. they all work fairly well while your sitting in the living room, whispering to each other on the sofa but as soon as your out side sitting on a noisy motorbike it all goes to pot. Interference from the engine, wind noise, vox not working as it should, wind noise and wind noise '>

I've had an eye on the autocom system for quite a few years. It's by far the best I've ever listened to in terms of sound quality and I'm told that you can still hear one n other upto and over 100 mph

I've gone for the slightly cheaper option of 2 way radio but still recommended by autocom, mainly because the Kenwood tip top ones are too bloody expensive not to mention a bit large looking.
I told Trigg I bought them, she said "I'll look forward to dueting with you" lmfao '> '>

[Mr Rizla]

Cant beat Autocom, tis that simple, and the current prices are great value for money. Only thing worth mentioning is that you will need the PTT switch feature, bout 38squid. When we tried to use vox at the weekend the bleep customs kept activating them each time they rev'd, now ordered '>

[Stu]

Vox should work shouldn't it??

[Mr Rizla]

It should yes, so if the 2 of you were away on a ride together (on the bikes) then it should work ok, however, as mentioned external noise can active them, also if your riding over 90 expect the headset to activate intermitently due to background wind noise.