| Welcome to the official Charlie Tango DX Group CB And Amateur Radio Forum. You are visiting the UK's biggest and most active CB Radio club.. We hope you enjoy your visit. Charlie Tango DX is a group dedicated to Hobby Radio Users in all forms, whether CB, Amateur, PMR446, Scanning and Short Wave Listening. We are a very active and friendly group that welcomes anyone from anywhere in the world who has an interest in Radio, regardless of their level of experience, their equipment, their location, or their radio preference. We have members varying from fully qualified operators on the Amateur Bands, to newcomers who have just bought a PMR446 set, and many CBers both old and new. All are equal on the Site. The CT Site contains many reviews, tips and modifications within the forums, and we take pride that no sensible question is ever left unanswered, and nobody is ever belittled or mocked for asking an honest question, no matter how simple it may seem. We were all new to the hobby once. You're currently viewing our forum as a guest. This means you are limited to certain areas of the board and there are some features you can't use. If you join Charlie Tango you'll be able to access member-only sections, and use member-only features such as customizing your profile, sending personal messages, voting in polls, viewing modifications and more. If you are not yet a member: Registration is simple, fast, and completely free. Simply CLICK HERE to start the Registration process. Your application will need to include your personal name and approximate location, it will require you to confirm your email, and then be signed-off by one of our Admin Staff, but this is usually completed within 24 hours (48 max) |
| DAB Antenna | |
|---|---|
| Tweet Topic Started: Saturday, 12. September 2015, 18:24 (841 Views) | |
| Chris9 | Saturday, 12. September 2015, 18:24 Post #1 |
|
26 Charlie Tango 469
![]()
|
Not been on in awhile, so hi guys. I know this is a bit off topic, but thought you guys would come up with some ideas. The guy who works for me on the farm wants DAB in his tractor because the station he listens to has moved there. So in order to keep him happy and working late into the night, have put in the radio. The antenna has been a nightmare however. The only thing that seems to work properly is one of these horrible flimsy magnet mount antennas. The cab of the tractor is fibreglass, but there is a small metal plate that was pop riveted to the roof (years ago) and the magnet ant works on that. However the first tree that he goes under down the road will just swipe off the magnet antenna. So I tried a powered splitter using the original antenna, and that seemed to work but after working in some fields where the land is low it cuts out. So I tried shortening it to match the freq 222.064 MHz = 0.642mm for 1/2 wave. I think. But this didn't work. The old antenna is on a side mount on the cab and doesn't appear to have any metal around it. So no groundplane I thought. The other think I was struggling to work out is the impedance required of the cable, is it 50 or 75 ohms? Anyway, I have now bought a new side mount with a 3/8 screw and spring and was going to cut a whip to go into it set a 5/8 wave. But have not done anything yet because the connector on the radio for the DAB is an smb type which is crazily small and the tractors roof will have to be removed to allow this and we have been v v busy on the farm of late. I'm concerned that I might find that doing this (lots of work required to get roof off) might result in it still not working with this homebrew antenna. Also going to have to get a coax cable with the connector already on the end from somewhere. The tractor needs a strong antenna with a spring or it will just get snapped off / knocked off etc. Sorry that was long. Any ideas come to mind? Thanks Chris |
| I'd rather be barefooting.... | |
![]() |
|
| 26PS001 | Saturday, 12. September 2015, 19:16 Post #2 |
|
26 Charlie Tango 1523
![]()
|
I done a mini review a while back about these car dab antennas. When I get home I'll to d it but I have to say its totally different to FM. With dab its all or nothing, with FM it fades but will still be there. I'll show you what I experienced when I get home. You could try a wire dipole on the wi dscreen but again I tried this, it was rubbish, outside mini magnetic antenna has been the best thing for me although I was going to make one at some stage. I ended up up with a mini magmount from halfrauds £15 it worked great, no pre-amp or anything just pure magnetic antenna Edited by 26PS001, Saturday, 12. September 2015, 19:19.
|
Charlie Tango member 26CT1523 since 12/11/14 Mark (252) thecobraman tribute youtube channel https://www.youtube.com/channel/UC-jDebaO5BGsAjdy3pNiG7Q | |
![]() |
|
| Chris9 | Saturday, 12. September 2015, 19:28 Post #3 |
|
26 Charlie Tango 469
![]()
|
yeah cheers for that. The mini mag from halfords is what we have at the mo and that works. But the first tree he goes under will smash that off, it's so flimsy it won't stand a chance. |
| I'd rather be barefooting.... | |
![]() |
|
| Chris9 | Saturday, 12. September 2015, 21:25 Post #4 |
|
26 Charlie Tango 469
![]()
|
OK, looked again at the tractor and realised that I could make a new mount like I did for the CB antenna on a corner of the cab. This should have a reasonable ground. But how do I tune the antenna, because I'm sure I can't just use an online calculator, because I don't know how the counterpoise will interact with the antenna. The only way would be to get an antenna analyser which could do 222Mhz (which I don't have) would I be right...? |
| I'd rather be barefooting.... | |
![]() |
|
| 26PS001 | Sunday, 13. September 2015, 03:41 Post #5 |
|
26 Charlie Tango 1523
![]()
|
This is a trimmed down version of a rather long review I did a while ago for another site, just left the bits in you need. I would try this magnetic antenna low down anywhere you can as it seemed to work well for me. Outside my house seems to be a really bad black spot no matter what Im using, sat nav, fm radio, cb radio but this worked well. ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- The guy in Halfrauds lol told me they have had no problems with the Autoleads DAB Film Antenna SMB - DAB-AA1 a windscreen type antenna@ £19.99 and that its the only antenna they fit although they do sell others. ![]() Magnetic Roof Mount DAB Antenna @ £14.99 ![]() The first test was with the autoleads dab film antenna smb-dab-aa1 stuck on the windscreen, the first one I purchased ..... ![]() You can see in this photo the lead is plugged in ![]() And here is the signal ![]() Now for the second test using the Sonichi Magnetic Roof Mount DAB Antenna, you can see its plugged in, the tape is only there to show its the other antenna, I hadnt even wired it through the car it was just to test first as I had already made that mistake once lol ![]() You can see here I wanted the antenna to be mounted in such a way that it wouldnt have an advantage over the on screen antenna, Ive stuck it on the wing low down, lower than the on screen antenna, and my car was parked on the drive facing the wall of our house, trying to block the signal here as much as possible. ![]() Here is a view from inside the car, this shows Im not giving it much of a chance to work. ![]() But here is the signal, a full signal. ![]() The centre of the roof is always the best but unfortunately the cable was not long enough so I thought I would give it a go on the boot lid, now again the centre is better but I wanted my antenna to work harder lol, so I stuck it on the end as close to the back window as possible, again I had full signal and the antenna looked more tidy. ![]() Their is no give with DAB though, it either works or doesnt, when you get a drop out its a full drop out where as FM/AM as you will know will just fade and crackle a bit until you get better reception. TBH I think DAB is a white elephant, I would have prefered all these stations to be in local FM. I only bought a DAB for absolute 70s/absolute 80s lol They brought out DAB because they said you would get excellent sound quality, what they didnt say is that would come at a cost to these radio stations so most of them or not paying for the best qaulity they can get (bandwidth), its all rather disappointing if you ask me. Edited by 26PS001, Sunday, 13. September 2015, 03:48.
|
Charlie Tango member 26CT1523 since 12/11/14 Mark (252) thecobraman tribute youtube channel https://www.youtube.com/channel/UC-jDebaO5BGsAjdy3pNiG7Q | |
![]() |
|
| Monster | Sunday, 13. September 2015, 11:59 Post #6 |
|
26 Charlie Tango 636
![]()
|
Hi Chris, I recently made a DAB dipole for my loft, works well enough. You'd probably find a 1/4 wave groundplane, at around 320mm would give a better match to either 50 or 75 ohm co-ax, than a halfwave. |
| They say hard work never killed anyone..........but why take the chance? | |
![]() |
|
| 1 user reading this topic (1 Guest and 0 Anonymous) | |
| « Previous Topic · Aerials, RF & QRM Section · Next Topic » |
| Track Topic · E-mail Topic |
8:48 AM Jul 11
|
All Rights Reserved - No Part Of This Site May Be Copied Without Prior Written Permission. CharlieTango.co.uk have a legal Common Law Trademark and Registered Copyright #S0RN-LTC9-8CXT-LZLU of the brand "Charlie Tango" since 2009 and related Copyrights in place for domain names, Logos, images, format and layout of this website and associated material. charlietango.co.uk & charlietango.uk
View My Stats
DOMAIN NAMES FOR SALE
ConspiracyEffect.com | V5Bid.com Auction | 041183.com | Hiya.Mobi | VR Portal.Net | TrainerSox.com | CoinStealth.com | ChoccyBox.com Domains | FlutterBets.com | CharlieTango.UK | HallmarkedGold.com | MozSubmit.com | HorizontalEarth.com
CharlieTango.co.uk contact email leewardill@gmail.com

















8:48 AM Jul 11