Transmission1

I've been playing around with PMR446 for a while now, Its a bit of fun bending the rules a bit with a licence free band, playing around with homemade antennas trying to get maximum range from little power.

While digging around in the loft, found my kids old walkie talkie sets, two handies and a little base station all on 49.860mhz. I've already fitted external antenna socket to the base and now making a decent antenna to play with.
Thought it might be an interesting band to play with as the Hams seem to do well on 6m (50mhz) with little power and big aerials!

Anyone else played around with 49 megs or interested in experimenting a bit?

Curny
SN02

Had fun playing around with 49 mhz handies back around 1992.
As well as managing to make a few contacts I modified one to increase the strength of the second harmonic creating an extremely crude pirate radio transmitter, the range was only about 1000 feet max though lol

Is this not illegal

49Mhz

Hi,

Before their mass migration to PMR446 , motor-bike schools around newport, cardiff & bristol all used 49 MHz.

I think Maxon used to produce a type-approved / licence free walkie talkie on that band.

Although the majority of high-power illegal cordless phones have now gone
from the band , in urban areas the sheer proliferation of baby monitors makes
any QSO possibility practically impossible.

What continues to amaze me is how many people don't appreciate that it is the poor receiver performance that limits the range of these things, and also dont appreciate how sensitive the microphones are.

I recall in my previous house , as well as having music playing loudly of a summer afternoon, My neighbours used to cause me QRM on 6m when their baby monitor was on . As well as flattening my DXTV installation.

Having sourced the problem, I wondered just how far away I coud hear the wretched thing, so with rock n roll music blaring out of the transmitter as a good indicator, I drove away from my house.

it was some 2.5 MILES later that it was finally completely swamped!!

Regards

BB

vhfer wrote:Is this not illegal

49Mhz

no its not.

funnily enough it was in 92 when i last did this and we also ended up broadcasting our extremely short range pirate on the 2nd harmonic (99.72)
aah happy days


sadly theres too many baby alarms here too or i'd be up for it

2.5 miles! wow

i suppose i shouldn't be surprised i once got 3 miles (on 87.5) out of an unmodified i-trip from ebay before batteries leaked and killed it
what sort of distances have people got from those 47mhz phones?

i vaguely recall seeing a 1 mile(?) for the 1.6mhz base station in medium wave news

What's the legal maximum power for 49Mhz?
And do most 6m ham sets cover this frequency?

bben95 wrote:What's the legal maximum power for 49Mhz?

Not absolutely sure, but it's in milliwatts.
I have Realistic and Maxon radios on this frequency and the only references to output power quote '10,000uV meter@3 meters (FCC Max.)'

bben95 wrote:And do most 6m ham sets cover this frequency?

I wouldn't have thought so - 6m starts at 50Mhz, although I'm sure someone on the forum may know a radio that can cover this

The license exempt 49MHz frequencies are:
Channel A - 49.830
Channel B - 49.845
Channel C - 49.860
Channel D - 49.875
Channel E - 49.890


Curny

My ts-2000 will tx from 49.005

Although not very active, this yahoo group is a good source of info if you fancy playing around with 49mhz:

http://groups.yahoo.com/group/49megahertz/

A search on there reveals max. output power to be 100mw. (this is aimed at US, but I think UK spec is the same)

Curny

In North America, they use Low Band VHF mobiles which will programme from 31 - 50 MHz and quite often output over 100W Not to put ideas into anyone's heads of course

So what easily available (and affordable!) radios are available that can cover these frequencies??

I quite fancy experimenting with 49Mhz.

Curny

Is the 49.86 allocation still available for use without a licence, and what are the official power restrictions?

I have a Maxon 49HD. I used to have a few 49Mhz radios when I was a kid.

I've got a pair of the 5 channel Maxon handsfree walkie talkies, one of which I've turned into a beacon.

I've also got a pair of these that are a pretty good start for experimenting:

http://cgi.ebay.co.uk/2-Five-Channel-49 ... 231120a241


Curny

My apologies to the moderators for discussing 49mhz in the 446 section...
(Well it is 446, we just lost one of the 4's and the 6 is the wrong way up...)