| 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) |
| Extending the Antenna; PMR 446 | |
|---|---|
| Tweet Topic Started: Wednesday, 6. March 2013, 15:16 (1,304 Views) | |
| Tea Boy | Wednesday, 6. March 2013, 15:16 Post #1 |
![]()
|
Afternoon All. I just wondered if the antenna on a standard, basic PMR446 set is subject to SWR of some sort. Having taken one apart i found that the antenna is just simply a length of solid core wire, so my plan was to lengthen said wire and run it up my 6/10 metre pole. A simple project to carry out but not sure if i would need to check SWR? As i understand it all antennas need to be tuned?? Any advice is appreciated |
|
See whats going on at http://www.youtube.com/V8CSW CT Facebook Page Proud to be part of the The CT eXtreme DX TeamCTX Facebook Page 26CT965 26CTX965 163CT965 163CTX965 | |
![]() |
|
| VoG | Wednesday, 6. March 2013, 16:44 Post #2 |
|
Yup ![]() ANY transmitter needs to have a resonant aerial, matched to the frequency, or it it likely to suffer damage. |
![]() |
|
| Miko | Wednesday, 6. March 2013, 19:32 Post #3 |
|
Hi Jason, it is possible that your performance could improve with an increase in antenna size, tho not guaranteed. I think if you intend to experiment, and thats what it's all about, then first thing is to measure the existing antenna and make any substitute a multiple of that measurement. If youcan beg borrow or obtain by devious means a swr meter that covers the amateur 70cms band you would probably be able to fiddle around and get a reasonable match. You wont harm the radio by keying up briefly to check the match as it is probably fairly low power anyway. Might try a telescopic car radio element as this would be very easily adjustable. Personally, don't think you'd get a terrific improvement , but you never know, at least it would amuse you for a while trying.............Miock |
![]() |
|
| Tea Boy | Wednesday, 6. March 2013, 20:45 Post #4 |
![]()
|
Yeah it is just an experiment as you say, always up for an experiment or two Like with 27 megs the antenna lengths are usually based around the wavelength of the band ie 36 feet. (1/4 wave antenna is 9 feet like the tank whip) I found out that the wavelength of the PMR446 is 67.2cm and i figured that multiples of that would be ok to use. This is not based on my extensive knowledge of antenna theory as i have none!! but just research i have done. Just realizing that these cheap PMR's don't allow the connection of an SWR meter anyway so I guess there is no real way to check! Considering that the pair of PMR's I got only cost me £6.00 i reckon for £3.00 its good for a punt!! I will be adding a UV3r or 5r to the kit which will allow for proper use of base antennas so i think i will give it a go. Will post the results, cheers
|
|
See whats going on at http://www.youtube.com/V8CSW CT Facebook Page Proud to be part of the The CT eXtreme DX TeamCTX Facebook Page 26CT965 26CTX965 163CT965 163CTX965 | |
![]() |
|
| Offplanet | Wednesday, 6. March 2013, 21:40 Post #5 |
![]()
26 Charlie Tango 104
![]()
|
The most popular course of action that people take is to remove the standard antenna and replace it with a RF connector like a BNC socket or with a short pigtail of coax with a BNC or perhaps a S0239 on the end. Within the radio, the centre pin of the new RF connector is connected to the point where the original wire antenna was connected and the outer part of the connector connected to the negative terminal on the battery. The socket will then allow the connection of an external antenna - a simple centre-fed dipole (160mm each side for 446) being a good starter. The SWR of the dipole should be there or thereabouts, which is good, as the 500mW output of these radios is probably not enough to drive a SWR meter anyway Coax must be short and of good quality as UHF RF leaks away rapidly on transmit and receive - the benefits of having the external antenna can quickly be negated by coax and connector losses |
|
The CT eXtreme DX Team [imgw=50]http://b1.ifrm.com/2510/101/0/p5000422/mountain.png[/imgw] CTX Founder Member and CTX Team Admin Callsigns - 26-CTX-104, 26-CT-104, 163-CTX-104, 163-CT-104 CTX on Facebook ![]() CTX on Twitter ![]() UKCBTV on Youtube | |
![]() |
|
| Tea Boy | Wednesday, 6. March 2013, 22:09 Post #6 |
![]()
|
Top Banana Gary!!! That's why I like this forum, there is always someone with a good idea to share!! That makes a lot of sense to have a connector of some sort rather than hard wiring solid copper core wire. Thanks all |
|
See whats going on at http://www.youtube.com/V8CSW CT Facebook Page Proud to be part of the The CT eXtreme DX TeamCTX Facebook Page 26CT965 26CTX965 163CT965 163CTX965 | |
![]() |
|
| 26 CT 356 Mike | Monday, 11. March 2013, 02:20 Post #7 |
![]()
26 Charlie Tango 356
![]()
|
THanks for this, this has answered a questions i was just about to ask. Have you had any joy? |
![]() |
|
| Sgt Bilko | Monday, 11. March 2013, 09:16 Post #8 |
|
108 Charlie Tango 302
![]()
|
This any good. http://www.oocities.org/euro446/ants.html |
|
QRZ Page - www.qrz.com/db/MM0IBE Scientist have confirmed alcohol IS a solution | |
![]() |
|
| Tea Boy | Monday, 11. March 2013, 16:23 Post #9 |
![]()
|
Hi Mike, I haven't managed to find the time to try, hopefully this week will see some progress, so many other things on so.....
Thanks for the link Paul, I have been looking at this website, good source of info. There are various things in the pipe-line for the PMR at the moment, will try to keep a record via the Youtube and post as i go. Will post the links Cheers Guys |
|
See whats going on at http://www.youtube.com/V8CSW CT Facebook Page Proud to be part of the The CT eXtreme DX TeamCTX Facebook Page 26CT965 26CTX965 163CT965 163CTX965 | |
![]() |
|
| Tea Boy | Monday, 11. March 2013, 22:12 Post #10 |
![]()
|
OK, so after a couple of hours in the workshop and the compulsory 5 cups of tea later I have come up with this... I reused the housing of the original antenna and heat shrank the coax into the radio, the outer braid is soldered to the negative battery terminal and the inner core is soldered to the original antenna terminal on the circuit board. Its a simple center fed dipole with 160mm legs I will give it a try as soon as I can to see how it fairs. ![]()
Edited by Tea Boy, Monday, 11. March 2013, 22:14.
|
|
See whats going on at http://www.youtube.com/V8CSW CT Facebook Page Proud to be part of the The CT eXtreme DX TeamCTX Facebook Page 26CT965 26CTX965 163CT965 163CTX965 | |
![]() |
|
| VoG | Tuesday, 12. March 2013, 09:37 Post #11 |
|
Nice job. ![]() But don't forget what Gary said,
Every inch you can shorten it will reduce the Loss, increase the TX Power at the Feedpoint and improve the RX. |
![]() |
|
| Tea Boy | Tuesday, 12. March 2013, 09:56 Post #12 |
![]()
|
Hi Steve, I have got some better stuff RG 213 but it wasn't until after I had finished i realised that I had used the wrong length. I should have known someone on here would have noticed my error, thought I could sneak it in under the radar......
|
|
See whats going on at http://www.youtube.com/V8CSW CT Facebook Page Proud to be part of the The CT eXtreme DX TeamCTX Facebook Page 26CT965 26CTX965 163CT965 163CTX965 | |
![]() |
|
| VoG | Tuesday, 12. March 2013, 10:29 Post #13 |
|
Not a chance! ![]() ![]() |
![]() |
|
| canuck7 | Wednesday, 14. May 2014, 13:27 Post #14 |
![]()
|
Its tricky tryin to put an external antenna connector on these tiny 446 rigs, usually cuz there is'nt a lot of room for the connector. i resorted to using a sattellite female socket one one radio. just be careful before you go attempting it.. |
![]() |
|
| 1 user reading this topic (1 Guest and 0 Anonymous) | |
| « Previous Topic · VHF and UHF (inc PMR) · Next Topic » |
| Track Topic · E-mail Topic |
7:21 PM 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













rsz_s1000001.jpg (88.63 KB)


7:21 PM Jul 11