Tait UHF

Noel Preston

Well-Known Member
#1
Is anybody here running a Tait UHF? I am looking at buying a refurbished TM8115 unit which is programmed at 5 watts but can be changed to either 12 or 25 watts via a toggle on the radio. I can have the option of 5 and 12 watts or 5 and 25 watts, which ever I prefer. It's a two position switch so can only have two choices. They are quite bulky and offer a bit of a challenge to fit. The seller claims they are 160 w x 170 d x 50 h, the Tait site says 195 w x 160 d x 50 h, I guess the latter figures are more accurate.
 

Blue_haired_man

Well-Known Member
#2
Is anybody here running a Tait UHF? I am looking at buying a refurbished TM8115 unit which is programmed at 5 watts but can be changed to either 12 or 25 watts via a toggle on the radio. I can have the option of 5 and 12 watts or 5 and 25 watts, which ever I prefer. It's a two position switch so can only have two choices. They are quite bulky and offer a bit of a challenge to fit. The seller claims they are 160 w x 170 d x 50 h, the Tait site says 195 w x 160 d x 50 h, I guess the latter figures are more accurate.
You need a license to broadcast at over 5W to be legal so might be worth checking the legalities of having a radio installed that can broadcast at 12 or 25W. Rather large fines if caught but I’d be more worried about the truckies catching up with you.
Cheers Leo
 

GaryM

Well-Known Member
#4
It isnt legal. But that doesnt stop people.

But unless the other radio you chat with is 25w, there is little to gain from it. I mean Ill hear you, but you wont hear me. In an emergency, maybe someone will hear you, and as long as you give enough info they can head out to find you, but you wont know they are coming, and youre screwed if they need clarification, or wont head out until you respond.

Not that them not hearing you helps either. But the end result IMO, its mostly a waste of time.
 

Noel Preston

Well-Known Member
#5
I was considering it as an emergency situation. Use 5 watts and if stuck somewhere as I am normally on my own maybe the extra wattage may get a signal out.
 

GaryM

Well-Known Member
#6
Sure you will get out (Tx), but nothing will come in (Rx) at the range of the 25w. It only transmits at 25, its doesnt receive any better than a 5. The communication will still need to be 2 way. What Im saying is, the person you are talking too, will not be able to transmit back to you, as to get to them you needed 25w, but they only reply at 5w. Unless of course we all have 25s.

What the other person hears.
You: Help me
Them: OK where are you?
You: Help me
Them: OK, but where are you?
Yiou: Help me

What you hear
You: Help me
You: Help me
You: Help me


You need HF, or sat phone to be properly covered outside the range of a 5w UHF. Not to mention the line of sight issues of the tight signal of UHF anyway. It will still be limited by obstacles, ignoring unreliable bounce, due to its signal shape
 

Blue_haired_man

Well-Known Member
#7
Just out of interest what are they worth? A 12W output isn’t going to help a huge amount more in mountainous country.
A plb may be a more reliable solution, but definitely has limitations as well, as in lack of two way communication. But once activated the cavalry is on its way.
 

Marck

Well-Known Member
#8
Hi Noel
Mate Tait make a fairly robust commercial radio they will take a fair bit of abuse. Probably not a bad radio if the price is right. As stated above anything over 5 Watts is not leagal. If detected by the ACMA they will most likely seize the hardware and if you are caught using it at higher tx powers they may chose to take further action as well.

The ability to TX at a higher power in an emergency is something that may be bennificial but you have to remember that the people you are talking to may not be able to talk back. Overall this is a bad idea and if used incorrectly by accident or on purpose will disrupt communications of people that really need help or to get information through remember that you may be transmitting over somone else’s call for assistance / recovery / whatever not knowing because you can’t hear them. UHF really is the wrong technology for solo remote travel I would be looking at HF or sat phone for voice or a PLB or spot tracker for emergency location positioning.

M
 

Noel Preston

Well-Known Member
#9
I realise nothing will get back to me if it requires more than 5 watts to get out. I was more interested in peoples thoughts on the Tait as regards quality. It has the additional feature of increased transmission but it is a large unit. I think they may be ex mine radios at a guess and have been fully refurbished and the asking price is $150. I have had UHF radios ever since they came in, in my semi trailers so I am not new to UHF but have not seen much about Tait radios.
 

Marck

Well-Known Member
#10
Price wise it’s seems fair for a second hand uhf. If its going to be difficult to install I would think you would be able to get a more suitable radio for similar money. It it should be robust if you plan on giving it a bashing. But it’s also big and ugly so if it’s a price thing keep shopping I recon. If it’s because you want a brick of a radio that is probably going to be tougher than a uniden or gme get your wallet out. Keeping in mind it’s still a second hand radio that can die at any time.
 

GaryM

Well-Known Member
#11
Icom are miltary spec, made in Japan. Can be found for similar price to comarable feature GME, cheaper than GMEs top of line units with I think smartphone wankery.
 

boobook

Well-Known Member
#12
Most commercial radios are build well but generally suffer in scanning because it isn't a big issue for commercial radios. I recently went through a thorough analysis on CB radios. High on the list were fast scan speeds for 80 channels, receiver sensitivity ( Which people forget about) and Mike controls. I don't know the tait, but you generally miss some important UHF CB features when you adapt a commercial radio.
I love how the ICOM has a good reputation based on the IC400 and 410 Pro being based on commercial ( MIL spec) units. The 440 has no commercial heritage. Actually the ICOM family comes out very poorly. it is about 3 db more deaf that a GME. Thats half.

But the worst thing is the scan speed which ICOM don't list on their web site.
The new GME's are 20ms per channel so it gets through all 80 channels in about 1.5 seconds. The best a IC 410 can muster is about 100ms per channel or 8 seconds for 80 channels. If you have CTCSS on it is about 40 seconds for all 80 channels. The 450 is not much better. I called them several times and eventually they confirmed the above figures.


IMHO these 2 features make the new GME's stand way out in front of anything else. More important than power output. though the Bluetooth think is a gimmick. They shoudl have done bluetooth headset connectivity. that would be great.
 
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#13
Bit late I know but Tate make bloody good units and have excellent support.
I've used a heap of their gear in broadcast environments. Its absolutely top notch gear.
Made in NZ, the cops and armed forces us it. Not cheap though.

There's plenty of non licenced people using 25w rigs out there.
As well, the mines guys and other commercial operators use 25w so there is a chance you will be heard.
In an emergency situation, I'd happily use 25w illegally in the hope that someone might hear me even if I could not hear them reply.
So what if its illegal. You've got to be alive to complain...
 

Noel Preston

Well-Known Member
#14
I went ahead an bought it. Works really well. I have only used it on 5 watts but the switch is there for 25 watts. It was cheaper than a regular uhf. Quite happy with it.
 

boobook

Well-Known Member
#16
Sure you will get out (Tx), but nothing will come in (Rx) at the range of the 25w. It only transmits at 25, its doesnt receive any better than a 5. The communication will still need to be 2 way. What Im saying is, the person you are talking too, will not be able to transmit back to you, as to get to them you needed 25w, but they only reply at 5w. Unless of course we all have 25s.

SNIP
Gary, that's an over simplification, and not necessarily true. There are a lot more factors at play in radio than the transmit power. Sure that would be a true statement for some situations like in hilly areas where line of sight is short, or if the radios were identical and atmospheric conditions were stable.

But not all UHFs are the same and a key factor is "link Budget" which describes the allowable db gains losses and ratings along the way. Many 4wders don't put much thought into their UHF purchase. Cheap UHF's often have poor receive performance, a forgotten factor as important, if not more than transmit power. For example some cheapies have a receive level of say -118 db - ie they are nearly deaf. a good one might have a receive level of - 130db - excellent hearing..This is often expressed in uV. Hand helds are one example of this, as are the cheap or old Unicoms and Oricoms and Aldi's. People never look at receive level when buying and think they are getting a bargain at $180. It is different to antenna gain and the base level of signal at the input to the radio. It's the floor level.

So if both are 5w, then the good UHF can hear the cheapie from a much greater distance than the cheap one can hear the good one. But if the good one also had 25W, it could punch through - or yell at the deaf one and the conversation distance BOTH WAYS has improved. Same story for a legal set up of a 1 W handheld talking to a 5W proper set up. There are so many crappy cheap UHF's out there that this would frequently have a benefit.

I am not endorsing power over 5W for CB UHF. It's illegal, but other practices such as removing the antenna from the bullbar and putting it on the roof, low loss coax, and appropriate gain antennas can achieve similar results, all contributing to the link losses verses the budget. Unbalanced power levels are commonly used in commercial and licenced applications, the same theory applies to CB subject to the applicable laws.
 
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