Cobra 29 st transmitt

[Coondog27]

I guys, fairly new guy here. I got my Cobra 29 second hand for doing some work. I had an older fiberglass antenna laying around from my old truck and hooked it up. The co ax is a dual antenna, but I only have one hooked up. Adjusted see using meter on radio, achieving a 1 on channel 1 and around a 1.5 on channel 40. Anyhow my problem is that when I keu the Mike, the meter pegs out, and when I do a radio check, the meter doesn't swing and no response back. I had a friend come over with his radio, cobra lx and he could hear me from across the yard, but I guess we never tried further. Any suggestions?

 

[Coondog27]

No one? Perhaps the radio has been tuned?

 

[9C1Driver]

If you have a co-phased antenna system you CANNOT just run one antenna, you must have two installed. The only other thing you could do is put a 50ohm dummy load on one end if you had to.

That said once your antenna issue is resolved and the SWR has been properly set you can begin. Make sure the radio is in signal RF mode for the meter. Next turn the soundcrapper, er sorry, soundtracker feature off. Set the mic gain at 2/3 and give it a try.
If you cannot get it working might be time for a bench test at a cb shop. I would not put more then 20 dollars into that radio. The soundtracker models are the worst radio's Cobra ever made sorry to say, but hey it was free right.

 

[222DBFL]

The dual coax you are using is a phasing harness and is 75 ohm coax. You have an open end without both ends of that coax being hooked up. You need to get a single piece of coax that is 50 ohms and tune the antenna with that. Use as short a piece of coax, 12" or less for tuning and then you can use whatever length you want after that. Place your meter as close to the antennas feedpoint with the short jumper and tune the antenna, then remove it and proceed to use whatever length reaches from point a to b. Or from the radio to the antenna. But you need to get rid of that coax phase coax setup for sure!! Also you could cut an electrically tuned 1/2 wave coax jumper for tuning your antenna. For the center of the CB band or 27.205 that would be a piece of coax approx. 15.191ft long using a velocity factor of .84. The formula I used is, 492 x .84VF, / 27.205. Which equals 15.191ft. A 15ft piece of coax should work fine. This will tune the antenna for the center freq of the CB band. From your SWR meter, if you use a 3ft coax jumper, subtract this amount from the 15ft piece of coax, which would mean you would use a 12ft jumper from meter to the antenna feedpoint and a 3ft jumper from the meter to the radio. This will keep the total length at about 15ft, and this should work for tuning your antenna to the center of the CB band. If you need longer coax, double the length of the coax as you want multiples of electrically tuned 1/2 wavelengths of coax. And to the others that will also answer to this post, if I have made a mistake telling this gent how to tune his antenna using only a SWR meter, please feel free to correct me!!! I hope this helps and that you get your issue resolved. Also remember you need 50ohm coax. So don't cut the harness you have now and try to use that as it will not work. If you want to tune the antenna for a different frequency, just use the formula I posted above, 492 x the velocity factor of the coax, then divide it by the desired frequency. And don't forget to take into account the length of coax you use between the meter and radio. This should in theory work. But I could be wrong. But I tnink I am correct. If you want to look up the way I did this yourself, google how to make a mm electrically tuned 1/2 wave coax jumper. Here are some photos of the page and info I used to get the length of coax. And again, make sure you use 50ohm coax. I hope this helps. Have a good one.

 

[Coondog27]

Alright, thanks for the help guys. I will purchase a single co ax cable to start.aybe I will invest in a Wilson mag mount 1000.

 

[222DBFL]

That would work much better than what you have now. And also may I suggest looking at the Sirio performer 5000 instead of the Wilson 1000. The Sirio performer 5000 and the Sirio PL145 magnet mount is a darn good setup and is longer than the Wilson antenna as well. And they seem to be better built antennas. JMHO. I've used both and the Sirio does in fact get better RX and TX then the Wilson 5000 I was using did. Not much, but enough to be noticeable. And tuning them isn't too hard either. Whichever one you get, be it the Wilson 1000 or the Sirio performer 5000, cut the antenna in small increments for tuning. I always recommend 1/8" cuts. Seems kind of small, but it keeps you from cutting the whip too short. And take your time. Have a good one. Here is a photo of a K40, a Wilson 5000, and a Sirio performer 5000 from left to right. Note the longest antenna being the Sirio performer 5000. Again, hope this helps and good luck with whatever you choose!! Good day.

 

[Coondog27]

Thanks once again. How did you like the k 40? I am also looking into the k30. Price is very attractive. I'm thinking about getting an SSb radio too. Which antenna would you recommend then?

 

[sonoma]

you are looking at the low end antennas and will not be happy with them. they work to a point. you need to look into getting a good antenna. you will find the better antennas are a much better performer. antennas are the most important part of your system.. you can put a cheap radio on a good antenna and it will work good.

 

[Coondog27]

222dbfl, I see you mentioned a meter. I am using the one on the radio (built in). I would like to get an external one, I was looking at the workman dual watt/see meter, but it seems to recieve negative reviews. Any one that is particularly decent around $40?

 

[222DBFL]

The workman HP201s or if you can find one, a radio shack SWR/watt meter. The Workman HP201S is about $38 on Amazon and the radio shack meter if you can find one in a store are $40. You can also find the radio shack ones on eBay as well. I use the radio shack meter myself when needed and it works well for both mobile and base use due to its size. The Workman meter is a larger meter. Some say they aren't good, some rave about them. And as far as antennas go, stay away, far away from the k30 or k40 antenna! They suck! The one I took a pic of was just for reference. The Sirio performer 5000 or the Sirio 5000 trucker series are both good antennas. Many members here use them and will vouch for them being a good antenna. They are about 7ft tall which is not shabby at all. And like I said before they are well built. But like I said, stay away from the K30 or even the K40. Length is key to a good antenna as well as the build quality and the Sirio antennas are good in both areas. No it's not a 102" whip, but it's darn close to one. Do a search on them on the forum here and you'll see that there are quite a few members that use them. I would recommend a hard mount over a magnet mount, but if you are dead set on a magnet mount get the Sirio PL145 one. It's made for the Sirio antenna. That or get a tri or quad magnet mount. A good hard mount that I have recommended to many is the Breedlove 3" one hole SO239 mount. They are built very well and work awesome with the Sirio antennas. Drilling a 5/8" hole is what is required for one of them. And if you decide to sell the vehicle, buy a cheap Wilson gum drop mount and replace it with the Breedlove one. Or even one of the shark fin type radio antennas would work as well. Don't be afraid to drill your vehicle, as in the long run the hard mount will be the better way to go. Less maintenance. With a magnet mount you constantly will have to constantly clean under the magnet and also make sure that no water or condensation or water gets under it either. Just some food for thought. Not saying they don't work. Just more work involved with keeping them working right. A hard mount is a one time deal and forget about it. And the Breedlove mounts are top notch. They cost more than the magnet mount, but I promise they are worth every penny!!
Hope all this info helps. Let me know if you have any other questions. And oh yes, as far as coax goes. Make sure you get some quality stuff. And I don't mean the truck stop coax!!
Belden, times microwave, andrew, commscope, shireen, Judd wire, 123 wireless, Davis RF, and a couple others make quality coax in all different types. Me personally for a mobile, I like LMR240UF. Yes some will say it's over kill, but it's good coax! These are all JMHO's, and some will argue that I am wrong. But most will agree that I am telling you the right stuff. Yes there are more expensive watt meters out there for sure. I just named off a couple in the price range you asked about that seem to work well for what they are. They are better than using the internal SWR meter no doubt!! And I am sure about that 110%!! That said, again, hopefully I have given you some decent info to get you going in the right direction. Have a good day.
73 and God Bless
Sean.

 

[222DBFL]

And oh yes, as far as an SSB radio. For the money you can't go wrong with the uniden 980. Anything else and you will be spending way more money unless you find an older used radio that works good. For the money the uniden 980 is hard to beat. And again, some will argue that they have issues. Leave the radio stock or have a good tech turn the power back and also check the bias voltage and you won't have any issues. That or add a small fan to the back. Yes they can get hot during long talks, but if you tune the power back a bit it helps a bunch. Just speaking from my own experience. I own one and have had it for about 3 years now and have had no issues with it. I did turn the AM power back to 2 watts dead key and about 8 watts pep, and on SSB I tuned the power back to about 8 watts pep as well. The radio stays cool now and hasn't given me any issues. Cost for one of these is just over $100 new. Check Amazon and you will find that for about $110 shipped you can get one brand new. Like I said. Hard to beat that price for an AM/SSB radio. Anything else is going to be almost double to triple or more in price.
Again, have a good one and I hope ally his helps.

 

[Coondog27]

How are the galaxy 959 out of the box. It is an attractive radio. I would rather have something that works with some minor tuning than have to open up the radio to have it work properly.

 

[Old_Crow]

Thanks once again. How did you like the k 40? I am also looking into the k30. Price is very attractive. I'm thinking about getting an SSb radio too. Which antenna would you recommend then?

Stay away from these short antennas, spend the extra $10 and get the K40 or a Firestick type antenna at a minimum. Also the cable is important, that's why some sell for $0.20 /ft and others $2 /ft.

 

[222DBFL]

The Galaxy radios tend to drift on SSB especially in cold weather. I would look at something different if it were me. But that is JMO. The Stryker 955 or an RCI2950 would be better radios than the Galaxy. Again, JMO. Or even the magnum 1 or Anytone 6666. Any of these will be a better radio then the Galaxy 959 IMO. Especially on SSB. Let some others post as well and see what gets said.

 

[Coondog27]

Awesome, thanks for your help. Like I said, I'm pretty new. I've always had one, just couldn't quite get it figured out and now I'm starting to get interest again. Watching dome of them guys shooting skip on YouTube is pretty entertaining. Hopefully I'll be able to do so shortly. I just ordered a Wilson 1000 mag mount. I was going to get the roof mount one, but I just can't quite drill a hole in my roof. I have a Texas Star dx100 that I may hook up too. Time will see pertaining to range also.