Greater Range with a VHF

Peter & Judy · Posted: Tue Apr 02, 2024 11:12 am Post subject: Greater Range with a VHF

Last year after the Friday Harbour gathering a group of about 12 C-Dories headed off on a cruise to Princess Louisa Inlet. We broke into sub groups and we were the tail end group, travelling with Colby on C-Travller. During this time we were making contact with some of the other groups via VHF. Often Colby could communicate with them, but we could not. Sometimes we could hear them, but not talk to them while Colby who was near us could. Our question, why might this be and how could we increase the range of our VHF? Colby had a devise to test our antenna and it tested fine. We are in a 22' and Colby was in his 25', so his antenna was slightly higher than ours.

My VHF radio is a Standard Horizon GX2200 which I installed about 5 years earlier with an 8 foot Shakespeare antenna.

BBlalock · Posted: Tue Apr 02, 2024 12:14 pm Post subject:

Could you have been on low power?
Benton

C-Wolfe · Posted: Tue Apr 02, 2024 12:20 pm Post subject:

I had range issues with my radio soon after I acquire my boat, my probleme was the antenna cable was fray at the bend where the cable enter the base. I couldn't find a good way to fix it so I just replace the antenna and that solve my range issues.

jkidd · Posted: Tue Apr 02, 2024 12:28 pm Post subject:

The cheap Shakespeare antenna less than $100 just has a wire glued into the fiberglass tube. The more expensive Shakespeare more than $100 has a brass element inside the tube. It depends on how well they tuned the antenna and what frequency they tuned it for. My personal experience is Shakespeare is an ok antenna and that is why I don't use them. My preference is the Morad Hot Rod VHF antenna. Everyone of these is hand tuned at the factory. I would mount it on your radar arch on a 1' to 3' extension. Vhf is line of sight so the higher the better. Good connections and good grounds are important and they don't last forever. Even Morad says their antenna is good for about 10 years. Find a Ham and have test the antenna with a analyzer.

jkidd · Posted: Tue Apr 02, 2024 12:32 pm Post subject:

jkidd · Posted: Tue Apr 02, 2024 1:04 pm Post subject:

One other thing that should be looked at would be your radio, cable and antenna could be perfect and if you just moved the port of starboard a 100 or 200 feet the problem would just go away. If you were sitting right where Colby was It might work just fine. So it could just be atmosphere.

thataway · Posted: Tue Apr 02, 2024 1:37 pm Post subject:

Jody gives excellent information as always! I also prefer the Morad antennas, which are tuned. These are commercial grade, used by military and Coast Guard. They also have a mini connector already on the cable so you don't have to solder or crimp the PL259 connector. With Morad, you have to specify the length of cable, and then use their connectors/mount. It is worth the extra cost.

Many of the problems are a bad connector at the PL 259. The Crimp on type that Shakespeare uses corrode with time and tend to not receive or transmit as well. I did a tutorial on soldering the PL259, but is probably not a job for someone who does not have soldering skills.

thataway · Posted: Tue Apr 02, 2024 3:49 pm Post subject:

Here is the link to the tutorial I did on soldering the PL259 connector.

Peter & Judy · Posted: Tue Apr 02, 2024 6:57 pm Post subject:

Thank you for all of the advice. I think that I will start with the connector and resolder it. If that doesn't help then I think I will shop around for a better antenna. The original antenna that came with the boat was fairly new and was a digital brand, I think it was better than the Shakespeare. I had to replace it after and unfortunate incident with a bridge. It might have also had a better connection. The one thing I have learned with fixing farm machinery is to start with the easiest and cheapest fix first and work your way up from there.

I'm pulling the boat out of storage after the snow storm that is brewing now is over and I hope to be crossing the Rockies on my way to Vancouver Island in about 10 days. I won't know for sure how well my repairs worked until I get on the water and maybe I can test with some of you when we are at Friday Harbour.

Thanks again.

gstraub · Posted: Wed Apr 03, 2024 5:41 am Post subject:

If you can hear them but not talk to them, the other thing to check, is the power output of your radio to see that is at least 15 watts (radios are designed for 25 watts). That was probably checked with the meter you mentioned. If it is low, that can be caused by excessive voltage drop in the power lead going to the radio. You can check that by measuring the voltage as close to the radio as possible on receive and then on transmit. It will drop some during transmit, but should not drop several volts. You'd be surprised how many installations I inspect and fail due to this problem. It's usually caused by corrosion in the power connections somewhere between the battery and the radio.

The other problem that can occur is if the coax going to the antenna has had the outer cover damaged or water has gotten into the cable, usually from cracks in the outer cover or at the connector on the antenna for antennas that have a connector at the antenna end, or sometimes through a leak in the antenna itself. While you'll usually see this problem using the VSWR meter that you mentioned was used, sometimes it only shows up as excessive loss. Also, if there is excessive loss in the cable, the VSWR will be made to look artificially better.

ssobol · Posted: Wed Apr 03, 2024 9:04 am Post subject:

Another problem can simply be the xmitter section of your radio. I had a radio fail in that I could hear but not transmit.

Hunkydory · Posted: Wed Apr 03, 2024 1:34 pm Post subject:

If you want better odds of extended reliability with it less likely to experience the trouble shooting hassle, that Peter & Judy are experiencing now & willing & able to spend the extra cost & labor for it, then go with the sound advice of Jody & Bob. On the other hand for me, the cheaper 8 foot Shakespeare antenna, that Jody mentioned as just ok with its non soldered standard Shakespeare connections worked fine for 21 years, outlasting two radios, that did quit transmitting. After going through the two cheaper Uniden radios, I upgraded to the Standard Horizon GX 2400 with its NMEA 2000 capability & to the better Shakespeare 8 foot antenna three years ago. Jody tested it for me & it was tuned where it should be from the factory. I have also always had on board one or two hand held VHF radios.

Like many things in life on an individual basis one must choose where to spend time & money for their best return & where it’s worth the gamble to not go top end.

Jay

ssobol · Posted: Wed Apr 03, 2024 3:23 pm Post subject:

Hunkydory · Posted: Wed Apr 03, 2024 5:41 pm Post subject:

colbysmith · Posted: Wed Apr 03, 2024 8:46 pm Post subject:

FWIW, my antennas are the Shakespeare 8', and mid range at around $130, I believe. I don't remember exact numbers when I ran the meter on Peter's radio, but power was within specs on both high and low, and the SWR's were in the green (less than 1.5 I believe). I have two radios in my boat, with two antennas. My one radio has always worked best. My secondary radio, even though I replaced it a year or two with a new radio, is still inferior to my main radio. That antenna use to sit about 3' lower, but I raised it last year to the same height as the other, and I'm not sure it improved that radios range. (Mounted on side of roof's high top.) (For either receive or transmit.) Perhaps I just have a very good radio that I use as the main. Perhaps it's the antenna cable length? Both antennas are the same model. Maybe the port side of my boat has a better ground plane... Mr. Green

Sorry Peter, I don't have any advice to offer. Enjoy the boating season this year. I probably won't get west this year, but you and all others are more than welcome to come out to our fresh water Great Lakes! Colby