27mhz radio

Submitted: Wednesday, Jun 01, 2005 at 13:11
ThreadID: 23491 Views:6334 Replies:9 FollowUps:6
This Thread has been Archived
I was wondering why UHF is more popular than 27 mhz SSB radios. The SSB type can transmit at up to 12 watts with up to 30km rangs (LOS) compared to 5 watt max (5-20km LOS) for UHF. Outback use will not have repeater support for UHF, and SSB is capable of skip (not to be relied on) of several thousand km's, also SSB radios are cheaper.
UHF has better clarity, and with repeater support can transmit up to 100kms, but this dosnt help in the outback!
Any comments?
Back Expand Un-Read 0 Moderator

Reply By: Member - Chrispy (NSW) - Wednesday, Jun 01, 2005 at 13:25

Wednesday, Jun 01, 2005 at 13:25
Colin - I may not be speaking on everyone's behalf on this, but the only time I really use my UHF unit is when I'm in line-of-sight convoys..... i.e. club trips.
AnswerID: 113895

Follow Up By: ColinD - Wednesday, Jun 01, 2005 at 13:36

Wednesday, Jun 01, 2005 at 13:36
True, but for this type of use would a normal 27mhz AM (non-SSB) be better value at a range of around 5-10kms, they are generally cheap at about $150. There is definately a trend towards UHF use, I want to purchase a radio soon and dont want to fork out more than I need to. Still I guess its of no use to have AM or SSB if you are the only one in a group with one.
0
FollowupID: 369947

Follow Up By: Member - Chrispy (NSW) - Wednesday, Jun 01, 2005 at 13:43

Wednesday, Jun 01, 2005 at 13:43
I think It's just a matter of clarity Colin - and that's all. I have both AM/SSB and UHF in our car - and the only one I've used over the last 3 or 4 years has been the UHF. No-one seems to buy AM anymore - well, not for club use anyhow.

If I need more distance than what UHF and repeaters give me, I make sure I have a satphone handy.
0
FollowupID: 369948

Reply By: Member - Geoff M (Newcastle) - Wednesday, Jun 01, 2005 at 13:37

Wednesday, Jun 01, 2005 at 13:37
Colin,
I think you've pretty much answered your own questions,
Citizens Band (CB) radio is really only designed for short range, line of site communications. As you've said, skip in the 27mHz range is not to be relied upon. (This I suspect would be more reliable when the Ionosphere is skipping the higher HF frequencies)
As you say, repeaters are the only way to get better than line of site out of CB communications and that includes both 27mHz and UHF.
Reallisticaly in the outback you may be the only person for several hundred kilometre's that owns a radio or has it turned on. Or on the right frequency for that matter.
In the scheme of the world, up to 20km is just as limiting as up to 30km when they both rely on line of sight.

The valid points you've raised are really the realm of HF, not CB in its two variants, 27mHz and UHF.
In my opinion, that's why HF is so much more popular for relaible long range communication than either 27mHz or UHF.
Guess I'm saying horses for courses and 27mHz versus UHF is up to the market to decide. This I believe it has, in favour of the clearer UHF signal.

Good questions, trust I've contributed,
Geoff.
Geoff,
Landcruiser HDJ78,
Grey hair is hereditary, you get it from children. Baldness is caused by watching the Wallabies.

Lifetime Member
My Profile  My Blog  Send Message

AnswerID: 113896

Follow Up By: ColinD - Wednesday, Jun 01, 2005 at 13:50

Wednesday, Jun 01, 2005 at 13:50
Geoff, thanks for that. I wasnt aware that 27mhz had repeater support. Could you suggest somewhere I could get location and channel No. for repeaters please. Help appreciated,,,,,,,,,,col
p.s. fully agree with HF, and would love to get my hands on a good cheap HF set if they exist.........
0
FollowupID: 369949

Follow Up By: Member - Geoff M (Newcastle) - Wednesday, Jun 01, 2005 at 14:14

Wednesday, Jun 01, 2005 at 14:14
Hello Colin,
I believe I've mislead you. My comment regarding repeaters for 27mHz was more about any line of site transmission benefiting from a repeater. Not an inference they exist in 27mHz. If they do, I'm not aware of them.
Please accept my apology for misleading you.
The following URL's whilst not specifically what you are looking for may help at another time,

UHF Repeaters

UHF Repeaters

The two URL's are to different sites, they fundamentally contain the same repeater information. They do have other two way radio information as well.

Geoff.
Geoff,
Landcruiser HDJ78,
Grey hair is hereditary, you get it from children. Baldness is caused by watching the Wallabies.

Lifetime Member
My Profile  My Blog  Send Message

0
FollowupID: 369952

Reply By: Member - JohnR (Vic) - Wednesday, Jun 01, 2005 at 13:49

Wednesday, Jun 01, 2005 at 13:49
Colin,

The usefulness you already say is limited with 27mhz. The old technology is just not there, as is the case for clarity and proximity.

When I started using UHF I used to use a 20 metre high tower for my base station and a repeater in the Otways gave us a range to the Westgate Bridge 200 kms as the signal goes. Have talked Western Victoria to Tasmania too that way. I have lost the interest in the skip I used to get on 27 mhz which was the first way we used radio for our business.

Normally can get much more reliable signal on UHF and you can limit or extend it by selection of antennas. You may be surprised at repeater locations too, just like to the west of Purnie Bore crossing the Simpson and many others, just check the locations under "On the Road / Repeater Locations" above. You don't have to worry about crappy skip either.

Some may like 27 mhz, but most as I, couldn't bother when you are trying to enjoy the sounds and the scenery of the location.
AnswerID: 113899

Reply By: drogger - Wednesday, Jun 01, 2005 at 13:59

Wednesday, Jun 01, 2005 at 13:59
The main advantage of UHF over HF is that UHF gives a cleaner signal. As UHF reception is limited to line of site (and repeater) there is a distinct lack of traffic on the channel. Also - a signal will (generally) either get through or it won't - signals are either strong or don't exist at all - there is no halfway.

With HF you can pick up lots of traffic - of varying signal strengths - which can all combine to make a lot of background noise and make it hard to pick out the signal you really want.

If you want to get reliable Skip - it is better to go for a proper HF rather than a CB type HF. The reason is that skip coditions change constantly due to weather, time of day, sunspot sycles etc. You really need to have a variety of frequencies depending on the condition at the time you use it - it may be 3 Mhz or 5 Mhz or 7 Mhz or 9 MHz etc. By locking yourself into one small range of frequencies (27 Mhz) - you are locking yourslef out of the other ranges of frquencies that may work better.

Cheers
Drogger
AnswerID: 113901

Follow Up By: drogger - Thursday, Jun 02, 2005 at 14:43

Thursday, Jun 02, 2005 at 14:43
One thing I forgot to mention is that UHF is consistent and predictable. If you can communicate with someone at location "x" and you are at location "y" - you can be sure that you can repeat that communication at any time.

With 27 Mhz you cannot have the same guarantee (especially with skip).

Drogger
0
FollowupID: 370081

Reply By: Kiwi Kia - Wednesday, Jun 01, 2005 at 14:21

Wednesday, Jun 01, 2005 at 14:21
Check out the Pink Roadhouse web site;
http://www.biziworks.com.au/pink/
And have a look at their map section and count the number of repeaters on the west side of the Simpson. Note that the coverage overlaps one another.

Also note the road signs for the Canning and the Simpson that indicate the UHF ch you should be monitoring.

The latest uniden 5 watt PRS (uhf)radios also have a simple gps included for a combined price of aprox $330.

Ray H.
AnswerID: 113908

Reply By: ColinD - Wednesday, Jun 01, 2005 at 15:54

Wednesday, Jun 01, 2005 at 15:54
Great thread, thanks for your input, regards.................col
AnswerID: 113915

Reply By: floyd - Wednesday, Jun 01, 2005 at 18:33

Wednesday, Jun 01, 2005 at 18:33
UHF can get better range than that if you are in a good position. Also if you communicate with a well located repeater you can get 100's of Kms.

I work on Mt Buller in Vic and can speak from my car via the Red Hill repeater (200 km's away) and talk to people on Phillip Island in westernport bay. I have even transmitted to Tasmania from Wilsons Prom. this usually occurs when the weather conditions are favourable. You would be surprised how far UHF can go if the weather and land conditions permit it. Range is limited in valleys, built up areas and forests.

Neither UHF or 27 megs should be relied apon for safety. Go for a sat phone.
AnswerID: 113941

Reply By: Nige - Thursday, Jun 02, 2005 at 01:27

Thursday, Jun 02, 2005 at 01:27
I think a lot of people got sick of listening to Taiwanese fishing boats broadcasting on unlimited power - UHF sounds clearer, like everyone said, and UHF sets generally have scan which I have never seen on a 27 meg. set. Nige
AnswerID: 114028

Follow Up By: Groove - Thursday, Jun 02, 2005 at 10:57

Thursday, Jun 02, 2005 at 10:57
I have a 27mhz radio that scans!
Cheers
0
FollowupID: 370066

Reply By: angler - Thursday, Jun 02, 2005 at 20:51

Thursday, Jun 02, 2005 at 20:51
UHF every time, 27meg is almost dead and buried. Always get the best aerial you can afford, The one that has a chrome bit about 6inches or 150mm long at the base with a spring below that is the better one. I won't go into how it works, believe me its the best. wholesale about $75.00, RRP I don't know, probably add about 20%.

If you really want better comms over long distances get a sat phone. HF is an option if you can get a license. Still an expensive option.
AnswerID: 114133

Sponsored Links