UHF range
Submitted: Thursday, Mar 02, 2006 at 21:02
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Exploder
Gday all, just after some opinions on this little matter.
Just did UHF range
test with my Brother who had an El-cheep0 Handheld .5-watt UHF lying around and we thought we would see what sort range it had around the suburbs.
The best we got was around 700Metres when it started to become too crackly to understand.
I went up a
hill and along the top following the road in an S shape then down the side where I lost him completely.
No surprise really. What concerned me was with my 5Watt in car unit he completely lost me as
well, until I got back in front of the
hill and within 900 metres of his unit.
This sounds a bit off to me, I was expecting to lose him rather quick but I thought that his unit would still pick up my transmissions no worries in that sort of range, or am I way off base on this.
The last time I rely used the UHF for talking at any sort of distance was 8 months ago, and around the metro aria I was easily getting more than 900metres out of it. In the country I often have it on CH40 and will pick up roadworks and other chatter from way out.
So is something a miss or am I way off base in my thinking.
It’s a Unden Unit UH-89 running a Mobile One 920mm antenna B/Bar mount, it’s a 4.5Db or 6Db module can’t remember as I brought it 4 years ago.
Reply By: arthurking83 - Thursday, Mar 02, 2006 at 22:05
Thursday, Mar 02, 2006 at 22:05
Hi Exploder,
I'm no radio comms expert...but my (very limited)understanding of how radio and radiowaves work is......
When you said you tested the range of the .5W handheld with the 5W car mounted radio, it kinda occured to me that regardless of how powerful your car radio is going to be, it wasn't going to hear the very soft .5W transmission of the little handheld! The advertised power rating is for the transmit power of the radio.
The receive power is less than half that on most car mounted radios.
(and I think about 1/10th on some handhelds, with a switch to increase the recieve sensitivity on some??
I'm guessing around 1/2W - 1W, for most car radios(an expert will confirm/rebuff this)
So unless the transmission is powered higher to clear the
hill, then not many devices will hear that 'whisper' of a transmission trying to overcome the
hill!!
Even if you had a reciever that had 5W reieve ability, it would almost certainly need lots of filtering to remove any interference it will also pick up from various sources in the vicinity!
If your
test Tx radio was a 1W or full powered 5W source then you may have heard it just a little bit longer, DOWN the other side of the
hill!
If you can get your hands on a scanner, try using that next time too....
I think they have higher powered receivers, you may find th escanner may have heard the .5W transmission just a bit better(??)
then there are other environmental factors to consider too, like interference.........
......waiting now for the comms experts, to come along and 'shoot me down'......!
AnswerID:
158201
Follow Up By: Exploder - Thursday, Mar 02, 2006 at 22:24
Thursday, Mar 02, 2006 at 22:24
The low power unit was stationary, standing on the front lawn, and I was mobile in the car with my 5W system, what struck me as odd was that as soon as I lost him he basically lost me too, even when I had come back around from the other side of this
hill, the range on the 2 unit’s was almost identical. But ones worth like $20 and the other $500 when I brought it 4 years ago.
Might Jump on CH8 tomorrow and do a Radio
Check.
FollowupID:
412580
Follow Up By: rickwagupatrol - Thursday, Mar 02, 2006 at 22:56
Thursday, Mar 02, 2006 at 22:56
mate, ch 8 is a repeater, you will be heard half way around the city.
a handheld has a limited range, your car jobbie has a greater range.
but, go around a
hill or through dense trees and they both turn to crap real quick.
i have a GME 4400 in my truck and can hear some blokes for
miles, others i lose as sonn as they go into anywhere there is alot of tall buildings or trees or,,,
well the list is pretty big.
rick.
FollowupID:
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Follow Up By: Exploder - Thursday, Mar 02, 2006 at 23:07
Thursday, Mar 02, 2006 at 23:07
Ok cool, probably just where I was that was the problem.
FollowupID:
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Reply By: Member - Doug T (QLD) - Friday, Mar 03, 2006 at 00:20
Friday, Mar 03, 2006 at 00:20
Well i guess there will be a lot of knockers on this one but on a few occasions between
Hughenden and
Julia Creek Richmond area just after sun up i was escorting trucks west on the Flinders Hwy and we were talking to and hearing trucks on the Landsborough Hwy near
McKinlay , i checked the GPS for a straight line to
Kynuna and it was 208 Klm, now this don't happen often ,The first time i experienced this freak reception was near
Julia Creek back to the Shell at
McKinlay and that was 108 Klm, please feel free to Call
McKinlay Shell if you have any doubts'
About your hand-held
well it depends on what power it is putting out and its quality,el-cheapo won't get farnor will it recieve
well either, but a good DSE or Uniden with 5watts and you'll be surprised how far they do get out,
AnswerID:
158254