Communicating between Cyclist

[presta]

To be honest, if you're using PMR446 you're probably going to be close enough to communicate verbally with them directly anyway.

The power limit for PMR446 is 500mW, that'll get you a lot further than out of earshot.

Have a look on the tandem forums - not that many dedicated Tusers on here - but it's something they actively consider. Motorbike riders too, but they mostly have powered systems. . Although tandems don't need the range the battery life is a massive consideration, volume ease of use while riding etc.

Radio for a tandem? All you need is an intercom.

Motorola UHF walkie talkies have a range measured in km. All perfectly legal. Used to have some mtn biking years ago.

The ones at the top of the thread quote up to 7km, which sounds about reasonable for a distance in reasonably good conditions.

Get some Boafeng (also sold as Pofung) 888S's and a programming lead.

They're 500mW, the same power as the ones the OP refers to.

if you stick to that licence free band no one will care

You can't know that you've stuck to your allocated band, there's more to frequency planning than that.

 

[Drago]

Er, if they're programmed with the PMR446 channels only it'd be impossible to stray from the allocated band. You did actually read my post?

The 888 is 5W (more likely nearer 3) but can be programmed to 0,5. That is six to ten times 500mW.

500mW on a crappy 446 Argos type handheld will barely get you beyond shouting distance, if even that as some one the ones I've tried have shown. They rarely actually make 500mW and, antenna efficiency is beyond woeful, receiver sensitivity is non existent jn many cases. A £300 Icom or Kenwood PMR446 might well manage a few KM in ideal conditions with half a watt, a cheap blister back job for £30 a pair simply will not.

These Motoroka jobs might quote 7km on the box, but I'll lay a tenner to charity now they won't d0 700 metres, and probably a lot less than that in an urban environment, wooded area, etc. Look for the 'ideal conditions' weasel words on the box. I've have a pair of Motorola 950s and 1100s the OP is welcome to try, the best ones they did, and 7km is utterly beyond fanciful.

 

[presta]

Er, if they're programmed with the PMR446 channels only it'd be impossible to stray from the allocated band. You did actually read my post?

Since you clearly know so much about it, why don't you tell us all how you know what intermodulation products your transmitter is generating when it mixes with other transmissions in the locality.

 

[Pat "5mph"]

Mod Note:
@presta @Drago your very interesting points are a (big) bit out of the OP's question.
He said so a few posts back.
Please consider suggesting other alternatives to the OP.

 

[neil_merseyside]

When I used PMR handsets in the Alps in winter the range even in clear sight was woeful, too much interference for the signal to carry (apparently). The better professional sets had a line of sight range of about half a mile, to maybe a mile, they don't work round corners too well obviously. In my summer Alpine job in the same area we had folk using 2 metre band radios that had massive range, OK it helped that one end was usually a flying paraglider but the range was occasionally 50 miles, with line of sight easily 10miles on the ground. These radios had Vox throat microphones and bone conducting earpieces (when flying), just PTT on the ground, bulkier than PMR but not huge.