Just asking the question if anyone has experience of using something other than the Paddle Antennas ( A 1031-U & A 2003-UHF) that Sennheiser sell when you want a little extra range.

I have done some research and found a company Link who have suggested three options from their product range: 1) FINDIPDUAL 2) EDCLIP 3) MINIDIP

The guy from the manufacturer says that the UHF frequencies that we use are not a problem for these antennas and if 5m of cable is used then virtually no loss of signal will be encountered.

I am using Sennheiser G1's racked up in multiples of 4 and have the Antenna Splitter (AS1) in the usual configuration.

Seems to me that if I am on the right track then could save a small fortune for having an antenna that doesn't say Sennheiser on the side of it as these alternative units are under £20 !!.

So if anyone has knowledge on the witchcraft of radiowaves or can offer advice then please comment.

Someone may yell DON'T DO IT as you will blow your receivers up and this advice would be most welcome albeit sad to hear.

Thanks in advance

Tarqs

One thing I can say, is that there's pretty much no way (unless god decides to alter the laws of physics) that a non active antenna like you've referenced could blow your recievers up. It may screw with your range, if it's wrong, but that should be about it. If I were you I'd try and blag a free trial, up against the normal foldaway antennas and the sennheiser paddle ones, and see if it works, then if it does (which there's no reason it shouldn't) then come back and tell us all about it and we'll all rush out and buy them as well!

Matt

Is it just me who can't get the link to work? Keep being sent back to a blue room page.

I use the Canford ones with great results, both Yagi and Dipole.

Would be interested to see which ones you're reffering to, and the associated prices.

Sorry if the link didn't work but try - http://www.badland.co.uk/


A concurrent post has been automatically merged from this point on.

An bit of an update from a mate who is well into his amateur radio - when I dropped him an email his reply read:-


"Guess you know you have hit on my pet subject in the Ham fraternity I’m the one who’s in the chair for antenna's, Badland good company here goes……

They are all good and will look professional when you set up, I would certainly go for a dipole as the does not require a ground (3 bits sticking out)

The FD is directional and will give you gain in the horizontal plain but a belt pack when attached will be vertical polarized so this tend to cancel out the gain due to cross polarization.

The EDCLIP 1PWW is a lightweight dipole is ok and can horizontal if required depending on how you mount it, this basically what I drew out when you was here.

I would favour the jpolf as this doesn’t need a ground plane due to the short tuning stub; also it has gain which is useful"

Tarqs

The only concern is that it says "log on to see trade prices". Do you have to be a trader to buy from them? What price is the Jpolf? I got all of my aerials given, but if it comes in as low as you say, this could be a contender. I actually need a UHF dipole to complete the setup, so this could be the one.

Antennas is something that has been of interest to me since I had my first CB at 12 years (quite some time ago!)....
Anyway I was looking for an antenna design for UHF radios for a while now. I wanted to build my own antenna to replace the rather expensive Shure ones that we have been buying!
I don' know what the Senn ones are but the Shure is a log periodic design which is pointless as it's a wideband antenna with low gain but it has a 6/10db gain masthead preamplifier on the paddle.
From my experience it is possible to get drop out over a 20 m room full of people from a Shure beltpack using the Shure rubberduck type antennas which are a halfwave dipole. This has probably the same gain as a log periodic except the shure ones have the amplifier which helps.

So with that in mind and looking at the badland website I would like to play with the BASE STATION ANTENNAE (Product ID: YA3UHF).
It has 6db of gain over the dipole and should be quite ok for close range use.

or the BASE STATION ANTENNA (Product ID: YA8UHF). Which is an 8 element antenna and should resemble something that you would see on the roof used for TV. this one has 13db of gain so should be good for a longer distance but will be a lot bigger and also more directional. Being more directional is good if you have problems with interference from other transmitters but not good if you have a large area to cover with radio mics.

Other things to note are that this antenna comes with an N-Type connector and not BNC although this is not hard to change and it doesn't say what frequency it is tuned for. This is quite important because if the receiving element is setup for say CH62 and you want to use it on CH69 this might make it less efficient. However that said if it were being used for transmitting this would be more important and you might not notice the difference with a receiver.

either way I would like to have a go with one of these antennas and see what happens. I think I would go for the 3 ele and keep it within 10M of the TX on a reasonable short cable (or a low loss one).

Also I was thinking of experimenting with a TX antenna, They are the wrong thing to use for many reasons but I reckon it might just be a good start!

I could rattle on a bit more about antennas but I will shut up about here.... I think what I have said it right, I'm sure someone will be along to correct me if not!

r

One thing to add...

Yagi antennae suffer from side lobes, which can sometimes give issues with intermittent drop out off-axis, especially when you have an entrance from a rear door, through the audience. If you're using diversity receivers, I'd be tempted to stick a Yagi on one, and a dipole on the other. The dipole won't have gain, but will sort out your side lobe problems.

As for distances, well ive succesfully used UHF and VHF radio mics from 25m away with no problems using the supplied baby aerials, so I think with some quality coax, and some decent aerials, all should be fine provided we're not being silly.

A note though on cables. Rule of thumb is that for every 10m of cable at UHF, you add 3db's of loss, so you need to make that up somewhere with an antenna that has gain, or an amplifier.

I have done some outdoor PA work at motocross events where wires are a no go. The presenter/commentator was using a Sennheiser EW145 radio mic over in a portacabin about 100M away. Using a 13 elememt TV aerial, the signal level was still excellent into the RX. This was then re-transmitted using a Sennheiser IEM TX and a second 13 element TV aerial over to the Start line PA using a Sennheiser EW100 RX and a set top aerial up on a 3M pole and also to the paddock area PA using a set top aerial on a 6M pole.

At one point I was going to get a TV arial for my Radio Mics seeing as they are drit cheap and are for the Right Frequencies.

Is there anything wrong with this?

Josh

Fraid so, they will be 75ohm impedence as opposed to 50, so you will see losses.

They also, no matter what you do, will always look like a TV aerial!!!!


Be careful transmitting through an antenna with gain (like a tv aerial). The licence free (and licensed for that matter) frequencies are for stated output powers (EIRP I believe) at the antenna. They would be 10mW for handhelds, and 30mW for beltpacks. Your IEM transmitter may be more, though I'm not sure.
By using an antenna with gain (6db for the sake of argument), your EIRP is increased, meaning that, on paper, you are breaking the rules of the license agreement.

I doubt you'd find OFCOM knocking at your door, but strictly speaking it is an offence under the Wireless Telegraphy Act.

TV antennas can work quite well for radio mic use but there are a couple of things to watch for besides the impedance already mentioned.

First, they can be quite directional. This can be an advantage if you are forced to place the antenna a fair distance from the source but, if close to the stage, can actually result in the transmitter wandering in and out of the optimum area.

Second, TV antennas are designed specifically to work in one polarisation or another. This is so frequencies for TV transmitters can be re-used at closer geographic locations--if the polarity is different any decent antenna will reject the polarity opposite to the one it is set for. The polarity of a radio mic transmitter is a bit of a movable feast. It's probably more or less vertical most of the time, but will vary as a performer stands or sits, turns a somersault or whatever. So long as you have sufficient system gain in the first place to put the TV antenna at a compromise between horizontal and vertical polarity you can usually get away with it.

Edited to add: I'm speaking purely about reception above. Adding extra EIRP with a transmit antenna will certainly put you in violation of your radio mic licence.

Bob