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hankyexpress
09-09-2016, 06:24 PM
Hi Everyone,

I'm just starting out on my CB journey and I have antenna issues that I would like your opinions on if that's ok?

Please feel free to point out my rookie mistakes.

I have a Cobra 25 Classic (from someone on facebook) hooked up to a Firestik mounted on a 24ft painterspole which is staked into my lawn. SWR is 2.5 on all channels and nothing is received.

Here are some pictures of my efforts so far. Any help with reducing SWR and getting to hear some voices is gratefully received.

Thanks, Hankyexpress.

221622172218

doughboy
09-09-2016, 08:22 PM
1st make sure no metal above the plastic insulator touches your pole mount 2nd move the antenna as close to the top as you can better to use a right angle mirror mount if you can get one that eliminates both problems 3rd it really will not perform all that well as mobile antennas are compromise antennas they work but not as good as full blown antenna a full size steel whip mobile antenna might work a bit better

FATKAT
09-10-2016, 08:37 PM
I attempted to do the same thing and never got it to work right. I had better luck using a mag-mount antenna on the top of my car parked in the driveway and running the coax inside to the radio. I made side band contacts to Main and Cali. with this setup and a stock radio.

222DBFL
09-11-2016, 04:17 AM
Yep. You would be better off building yourself either a vertical, inverted V, or horizontal dipole for what you are trying to accomplish. If you were to use the existing painter pole you have and run a piece of wire down it and use an SO239 and a 1:1 balun or a piece of 75ohm coax for a matching stub, you could have a better vertical antenna.
If you have any trees in your yard, you can hang a dipole up between 2 of them. An inverted V or horizontal dipole would work well for DX'ing and locally out to about 3-5 miles. It doesn't have to be very high off the ground. 18ft or more is optimal, but I have seen them as low as 9ft and work well. There are tons of videos and also antenna calculators on either the App Store or android play store for the antenna calculators for the needed lengths of wire. Also Google 11 meter dipoles and you will see that there is a ton of info on this subject that will help you as well. That or you could build a vertical antenna with 4 102" whips and a 4-6" spring for the vertical whip. The other 3 will be used as ground planes or counterpoise. Like I said, Google is your friend and holds vast info on this subject. But I have to agree with the others here. The setup you have currently isn't going to work very well. Mediocre at best. But that is JMHO. The cheapest route is to build a dipole IMO. You can use wire or even a piece of coax. And you'll need some 75 ohm coax or a 1:1 matching balun to get the impedance to 50 ohms. Also eBay sells dipoles anywhere from $15-$45 dollars. Anyone of them will work. Just have to use your imagination sometimes. Again, these are JMHO's. Hope they might give you some food for thought and possibly some direction. Good luck and keep us posted as to what you end up doing. And we are here to help as always. It might take a few days for someone to answer, but there are many knowledgeable gents here that will help!! Again, good luck and be safe. Have a good day.

hankyexpress
09-11-2016, 08:44 AM
I really like the idea of using a mag mount on my car and then running the coax to the radio. I nearly bought a mag mount when I purchased the firestik too.

I am considering making a T2LT dipole antenna following the instructions of UKCBTV on youtube (https://youtu.be/senQ5_fc5WU) that has a blaun/choke in the design. It would be easy to strap that to my painters pole. I have 100ft of RG8X and I only need around 50 to 60 ft of it to get to the center of my lawn. The rest could be the dipole.

The other idea I had was to go a different direction and splurge on an IMAX 2000. But then there are additional costs for the mounting bracket to mount it to my garage, the extra ~$100 for the ground plane kit for it and then more money for copper pipe(s) in the ground to ensure it's electrically grounded as I live in an area where we get lots of entertaining thunderstorms.

hankyexpress
09-11-2016, 04:33 PM
So today I made the T2LT antenna and attached it to the painters pole. I managed to get some reception which was great. My SWR's were ch1=2.5 and ch10=2.8 too high to risk transmission. I think my balun needs to be about six foot off the ground which means I need to rethink my mast as the painters pole is too short. I'm thinking that raising the antenna will reduce the SWR - is this correct? Also the plastic pipe adaptor I'm using as a balun is 4" not 4.25" in diameter, do you think this will make any difference?

Guidance and comments gratefully received. Thanks for reading.

Hankyexpress

2219222022212222

222DBFL
09-11-2016, 05:40 PM
Your antenna might be a bit long. Here is an antenna calculator for making dipoles. Note the length for the each leg of the dipole, I.E., the center and outer shield. Cut the same from both when you cut. And only cut about 1/4" at a time and see what the SWR is after cutting. Also take a reading on channel 20, which is approx. the middle of the CB band. Then 1 and 40, this will tell you which way you need to go. But for now it appears that you have it too long looking at your SWR readings. Also make sure that your balun is as close to the connection point as possible or it's not going to work correctly. Like where the end of the shield or the other half of the dipole is. Here is a pic of the T2LT dipole for reference. It has the lengths that will get you close and also how to place your choke. http://uploads.tapatalk-cdn.com/20160911/b3d071c31b4128aeef8a947905139383.jpg
Hope this helps. Keep at it. You'll get it right. Don't give up!!

222DBFL
09-11-2016, 05:49 PM
You also need to use some RG59 or 75 ohm tv coax. Used for your cable. Do some more research on how to build the antenna properly.
Also you can use the antenna in an inverted V or horizontally and it will work too. Just not as well for local comms. Here are measurements for them.
Also included are measurements for a vertical antenna. http://uploads.tapatalk-cdn.com/20160911/04df9fc3254d581e37a419fe7360bb75.jpghttp://uploads.tapatalk-cdn.com/20160911/73066174ed8a61a508a75d73e1ea9d68.jpg
Again hope this helps. Have a good one.

222DBFL
09-11-2016, 05:52 PM
Also both I made the antennas above at the frequency of 27.205, which is channel 20 of the CB band. The middle of the CB band. Again, hope this helps some.
Also try cutting your current antenna a bit and see what happens. Or just fold the wire back on top. Might help bring the SWR down.

hankyexpress
09-11-2016, 06:28 PM
Also both I made the antennas above at the frequency of 27.205, which is channel 20 of the CB band. The middle of the CB band. Again, hope this helps some.
Also try cutting your current antenna a bit and see what happens. Or just fold the wire back on top. Might help bring the SWR down.


Thanks for all the info :-) Great diagram! The measurements are different to what I used today, but that's great. I did try folding down the top of the antenna and the SWR went up. I didn't realize that taking a reading at ch20 will help me work out which end to change the length of, I thought you only changed the length of the tip. I'll have to remove the zip ties from the balun and use something else until everything is all working great.

I'll give your suggestions a whirl this week on my day off and see what the SWR measurements are like. I'm not going to give up, the more it doesn't work the more it's fascinating why the hell not. lol

Thanks again for your help. I'll take a look at those apps too.

Hankyexpress

222DBFL
09-11-2016, 07:15 PM
No worries. Here to help all I can. Just ask, and if I can help I will. Hope you get it right. It takes some time. Don't worry I went through this myself when first starting. But at lead you are trying to learn. Again, good luck and be safe!!

hankyexpress
09-12-2016, 03:13 PM
So will the measurements in the drawn diagram be different if I'm using RG8x? It's 50 Ohms is it important to use the 75 Ohms instead? If so why is that?

Thanks

222DBFL
09-12-2016, 07:33 PM
The piece of 75 ohm coax needed is to bring the impedance back down to 50 ohms. So some reading on what impedance is and how it works with antennas. It will explain a lot as to why you may need it. You can also use a 1:1 matching balun or about 12 mix 31 snap on ferrite chokes as well.
The reason you may be seeing the 2:1 VSWR readings is to due to an impedance mismatch. And the 75 ohm piece of of coax will bring the impedance back down to around 50 ohms. Also so will a 1:1 matching balun or a choke or even ferrite chokes as well. Read up on how dipoles work and how they need to be built to work properly. There is more to making an antenna than just an SWR reading. Just know that. I won't go into detail as it may really confuse you. But I suggest reading and researching how to build a proper dipole antenna for 11 meters or the CB band. Google will have tons of info on this subject. Hope this helps.

222DBFL
09-12-2016, 07:51 PM
Here are some pics of an 11 meter dipole off eBay. Note the prices. The last one I posted is the best one as it has a 1:1 matching balun and will just need to be hung up between 2 trees or wherever you can get it up at least 18ft off the ground. The higher the better. http://uploads.tapatalk-cdn.com/20160913/3d35363741753e7a3b1c519d0f9eebf7.jpghttp://uploads.tapatalk-cdn.com/20160913/d4da408f023a799e1bf23447c80ed3c6.jpghttp://uploads.tapatalk-cdn.com/20160913/1fe701ecc00d461a1ad5c2051859f34c.jpg
I'm not sure about the 2 first ones I posted as to having a 1:1 balun, but the Dr. Dipole one does have one and they do work well. Placed as an inverted V, they work good for both local and DX work. Placed horizontal they work okay for local and very well for DX. Just some food for thought. You can try one of the less expensive ones and see what happens. I've heard good things about the cheap one actually, but have never used one myself. I have installed a Dr. Dipole one and it worked very well. Placed up between 2 extendable painters poles or even extendable fishing poles for crappie or spec fishing they work well. You know where to get the painters poles and the extendable fishing poles can be bought at Walmart or most any freshwater bait and tackle shop. Or just try using what you have. Split the coax like you have it and instead of trying to use it vertically, hang it up as an inverted V or horizontally between 2 trees or painters poles or extendable fishing poles. They don't have to be 18ft off the ground.
As a matter of fact the 1st dipole I built was maybe 10ft off the ground and I was able to talk to Australia from Daytona beach, FL. Not bad considering I was using a 12 watt uniden pc122xl on 38lsb. The conditions play a major role in how this happened, but the antenna helped. Again, I hope some of this helps and keep at it!! You'll figure it out. Be safe and just take your time.
73 and God Bless.

222DBFL
09-12-2016, 07:53 PM
Okay. I see now the 2nd and 3rd dipoles I posted do include a 1:1 matching balun to keep the impedance at 50 ohms. This will keep your radio happy. Again, like I said, do some research into the antennas before you continue to get an understanding of what you are trying to accomplish. JMHO. It will help. I promise.

222DBFL
09-13-2016, 04:54 AM
Let me also say that with the CB band or 11 meter band being pretty much dead, that now would be a good time to focus on some learning and also think about what you want to accomplish as there is not very much if any DX at all at the moment. That being said, an A99 or similar would work for local use. As much as I don't like them, they are very easy to setup and you might even be able to find a used one locally. Or one that someone isn't using and will give to you. It's how I got my first antenna. Given the area you're in, OH, I would think that there will be an increase in the sales of many base and mobile radios as well as antennas and towers/masts. Check your local Craigslist and see what pops up. You might just get lucky and find a decent antenna. But like I said, the band is pretty well dead. So trying to spend a bunch of money on stuff wouldn't be my first thing to do at this point unless you are certain you have many or even some locals to talk to. I don't care if you have 1000 watts at the moment. Won't do much good when there is nobody on the other end to talk to. JMHO's. Best thing you can do is to get your learn on and figure out a way to either build an antenna or find one that someone isn't using. Again, JMHO's. Have a good day and good luck with everything.
73 and God Bless.

hankyexpress
09-14-2016, 12:29 PM
I really appreciate your frankness. At the moment I'm satisfying a boyhood dream (albeit in my forties!) of using a CB and I've only had it for a few weeks. The effort I'm putting in now is toward getting my first antenna up and finding out who if anyone is out there around me locally. I am already considering HAM radio as a future interest to follow on from CB once I get my head around some fundamentals. HAM equipment is generally far more expensive than CB as far as I can tell. So it's going to take time to save for this equipment, in the meantime while saving I can study for the licence and join my local HAM club. Dipoles seem like a good idea especially when I consider that I can use them for both local and long range communications. If there's nobody locally, will the dipoles range in normal conditions mean that I should be able to find people, or are you saying that the CB band overall in the US is basically dead and over with and that I would be better to sell my gear and save for my HAM equipment?

I found a local HAM operator working in my local Lowes and he thought I should sell my CB equipment.

Thanks

Hankyexpress

222DBFL
09-14-2016, 01:01 PM
Yep. About the gist of it. I wouldn't go blowing a bunch of money on CB gear at the moment. I own a HAM or HF radio, and Icom 746. It was my 2nd HF radio, a kenwood ts140s i paid about $300 for being the 1st. And both will transmit on the CB band. While the AM side of the Icom isn't the best, the kenwood doesn't do so bad on either SSB or AM. My Icom 746 cost me more, but has served me well using it for SSB on 11m.
All that aside, build yourself a dipole and put it up as high as you can. There are several ways to utilize them for both local and long distance comms. But if you read around and speak to some others, you'll soon see the CB band is dead. The DX cycle is over and won't start again for a few years. This doesn't mean you won't hear DX at all, just that the chances are much less. Best to hold onto what you have and if you are going to get your ticket, just go that route. But I know there will be nay Sayers. I haven't gotten mine. By choice more then knowledge. I have studied for mine but just have a hard time wanting to register all my stuff. Know what I mean. Not that the FCC has the man power to catch every law breaking person, but hey anything is possible. All it takes is a phone call from a put ad neighbor about something and you have them at your door wanting to look at all your stuff.
Again, odds are most likely you'll get ran over by a bus, but there are still the odds. Don't let anyone stop you from doing what you want to do!! I'll say that. But for now, I would really look into whether you have any locals to speak with before you go spending a bunch on antennas and radios for CB use or the 11 meter band. That is JMHO. My radio hasn't been on in days. And that isn't like me. But there just isn't anyone around. Unless you like sitting around all day and maybe catching something you won't have much luck at the moment. Again, JMHO. If it were me, I'd get a decent power supply like the ones I posted. The S400-12 or the S700-12 being top of the list and use what you have for now. If you want a good radio that won't break the bank truly look at the uniden 980. Great AM and SSB radios for the money. And then either build or buy a dipole, which can be used again for both local and DX comms depending on how you place it up. In an L form, it will give you local comms and some DX, as an inverted V it will give some local comms and pretty good DX as well. As a horizontal antenna it will work out to about 5 miles locally and pretty darn good for DX. But like I said, the band is pretty well dead. An Antron A99 placed at 30ft or higher would work well or even an IMAX 2000. They are pretty broad banded as well and can be used on other bands such as the amateur ones. Use an antenna tuner and you'll be set. But like I said, for now, learn how to build a dipole and see what you get. Just need a power supply if you have a radio you can use. If not, again, look into the uniden 980. It does both AM and SSB. And they are good radios for the money. JMHO's. And again, if you are truly wanting to get your license, don't bother buying much. Just study and get your ticket and then save up and get a good HAM Radio. Doing some research you'll understand why I say all I have said. The DX cycle being dead and not coming back for a while and when it does will it even be that great? These are things I would look into first and foremost before you make any rash decisions. I am a cb'er at heart, but I too am looking to attain my license one day. Not right now, too many politics!! But don't let that stop YOU!! Do some real research for yourself and then weigh the options is all I am saying. Hope this all helps. Have a good one.

222DBFL
09-14-2016, 01:03 PM
I have given some info to another member as to what power supplies I would get. The thread name HELP. Read it and it should help some as well. Good luck with whatever you decide and have fun. That is the main thing!!!!

FATKAT
09-14-2016, 01:09 PM
Once I found out what channel the locals use I found there to be a good many around me. I just had to know where to look and then wait a listen. I can get out 20 to 30 miles with my set. I use a Uniden 980 and a Siero Tornado antenna.

222DBFL
09-14-2016, 03:17 PM
Thx FATKAT. Trying to help him out not to spend a bunch. As I'm sure you know as well that the DX is about DEAD!! Forgot about the Sirio tornado! And i had one LOL!! The Sirio vector 4000 has been one heck of an antenna to me!!! Getting out to 60+ miles is no issue at all these days!! Wild what a taller antenna will do. The vector 4000 being about 28ft tall. A little longer than the tornado. But more susceptible to bad weather if not setup right. Mine is only 27ft off the ground. Tip height is right at 54-55ft. It's one long antenna. Here is an old pic. It's still the same!! http://uploads.tapatalk-cdn.com/20160914/8d404d5f23880b3e93ad44ad97a66186.jpg

222DBFL
09-14-2016, 03:20 PM
Weather has been rough here the last few days. Lots of rain, wind, and T-storms!!! But it has survived very well! Fingers always crossed.[emoji28][emoji28]

222DBFL
09-14-2016, 03:21 PM
Hope you guys are staying dry!!!

hankyexpress
09-15-2016, 10:22 AM
I'm going to adjust the DIY T2LT if that fails buy the Dipole for 11 meters like the one you posted Big Hitter. After that unless the SWR is workable and there are locals around me I'm going to save like you suggest and go the HAM route. It is what it is.

Sunny and cooling down here in OH, probably gonna snow next week and that will be it unit April next year lol.

Hankyexpress

222DBFL
09-15-2016, 06:32 PM
If you do buy a dipole. I recommend the dr. Dipole. It is pretty well setup out of the box. Just hang it up as an inverted V and use it. They come with a 1:1 matching balun and they are well made. VSWR should be pretty good out of the box as well. But like you said, try what you have now and see what you can get. Look at the photo I sent you as well. This might help a bunch with setting the t2lt antenna up. Good luck and hope you get it resolved!!!

BOOTY MONSTER
09-25-2016, 10:25 PM
if you're gonna be making antennas read up on ground elements , they are crucial ! i had better performance with 1/4 wavelength (9 ft) ground elements than shorter ones ....

http://www.cbjunkies.com/threads/198-a-few-links-to-info-on-ground-planes-that-home-brewers-may-find-interesting