SteveShannon

Welcome!

It might be impractical. The 6 db antenna might be a 5/8 wave antenna and the lower gain might be a quarter wave. If you want to see what it takes try simulating the high gain antenna and then see what it takes to make it into a quarter wave. Personally I would try the antenna you have. If it works well enough just use it. Otherwise sell it and buy the antenna you want.

Well, I’m assuming some things based on squinting just right and experience with friends’ Siri transcribed sms messages. I really don’t know.

The other post sought frequency information:

The person whose GMRS license posted this message (Darre Fisher in Lynchburg, Virginia) is a petite lady who teaches at a Christian pre-school. I suspect someone else used her name to obtain a GMRS license or looked up her license and used the public information to register here. Another similar poorly worded post appears elsewhere on the forums. The poster appears to be desperately attempting to call a Walgreens truck driver back. Hopefully this gets straightened out, but I don’t think there’s anything we can do to help.

In fact, neither “weatherproof” nor “waterproof” actually mean anything in the absence of quantitative data. They’re marketing words, meant to attract customers rather than tranquilizing them with the language actually used in standards. For instance, “waterproof” means nothing without some kind of data about water quality, water pressure, and period of exposure. Fortunately, Amphenol knows the value of standards and they included the standards the two N connectors comply with. The “weatherproof” one has passed mil std 202, method 106 which is very stringent. It’s a short standard, totaling only a few pages describing the torture to which these connectors have been exposed. https://landandmaritimeapps.dla.mil/Downloads/MilSpec/Docs/MIL-std-202/std202mthd106.pdf The other N connector, which Amphenol attaches the marketing phrase “Extreme Exposure” to has passed IP67, which means it can be immersed in fresh water for thirty minutes at a depth of up to one meter. Now I don’t know Leo’s exact circumstances, but I doubt that mast on top of his building ever experiences the extremes reflected by either test listed above. Certainly if the connectors are immersed he has problems worse than SWR. And I agree that the connectors should be covered with glue lined heat shrink if they’re going to be mounted permanently. I’ve never said different and neither has tcp2525. So let’s stop arguing over the meaning of marketing language and take away some actual knowledge.

There is a law. Actually there are several in the Communications Act of 1934 and the amendments from 1996. https://transition.fcc.gov/Reports/1934new.pdf The law says follow the regulations or be fined.

Or one of the radio manufacturers (or both) saved money on a less expensive CTCSS circuit.

His was a Hustler antenna that was struck by a bird. Here’s the thread:

Alright, I’ll quit looking. If I come across it somewhere in single quantities I’ll let you know, if you want.

I’m not sure if you’ve seen this and perhaps the STUF just isn’t available anywhere, but this map might help you find a distributor near you. http://crossdevices.com/cross_devices_website2018_022.htm

Ahh, bummer. Sorry about that.

ARS still lists it for $8/tube. https://amateurradiosupplies.com/products/stufsealant-stuf-dielectric-water-proofing-sealer

Good point!

I don’t recall anyone suggesting they shouldn’t be wrapped, but Amphenol sells them as weatherproof and even has N connectors listed as suitable for extreme exposure. https://www.amphenolrf.com/rf-connectors.html?applications=638350

You’re right. Here’s the drawing from the data sheet (Amphenol website, not YouTube) and a list of the mil-spec for moisture resistance.:

You’re wrong. From Amphenol, note the word “weatherproof”::

I wouldn’t start throwing things away. I’m not even sure that what you did is related to the problem. You might end up replacing the cable or part of it but you can sell the antenna or change the connector at the feed point.

My suggestion is to set the transmitting handheld to transmit on 467.600 MHz. Don’t worry about setting a CTCSS tone. That will come later. Set your second radio to receive on 467.600 MHz and be absolutely sure no RX tone is set or required. Give the receiving radio to someone and have them go 50 or 100 feet away and listen. If they don’t hear you transmit one of the radios isn’t working.

A full duplex repeater cannot transmit and receive on exactly the same frequency simultaneously. On a single antenna system the two frequencies must be different so the duplexer can prevent the full power of the transmitter from overwhelming and damaging the receiver. That’s also reflected in the regulations. We transmit to a repeater on the 467 MHz main channels and we receive from the repeater on the corresponding 462 MHz main channels. The only time you transmit and receive on the same frequency is when you communicate on simplex. That’s all preprogrammed on certified GMRS radios so you wouldn’t have to program it in.

What kind of coax are you using? Specifically, what’s the dielectric made of? Here’s an interesting article about dielectric changes over temperatures.. https://www.microwavejournal.com/articles/27954-minimizing-temperature-induced-phase-errors-in-coaxial-cables

Repeater frequencies are 5 MHz higher on transmit than receiver. They have to be.

Maybe it’s related. Maybe it’s your antenna that’s changing. “Kids”. Ha! my wife reminds me that I'm an old man

On an antenna I could see the dip shifting left or right as the length changes with temperature. It would be interesting to chart the dip frequency versus temperature.

Certainly water in coax will absolutely mess up impedance, which appears in the SWR. I wouldn’t argue otherwise, but the water damage is usually permanent and requires that cable be shortened to remove the waterlogged area.. I just don’t know if freezing that water then somehow restores the impedance of the cable. If so, maybe freeze drying a cable would be a possibility to permanently remove the moisture. (Pure irresponsible speculation on my part!) I agree SWR shouldn’t change like that and I think you’re smart to watch this and chart the SWR and temperature over time. I would be interested in knowing if the SWR dip associated with the antenna raises and lowers or moves side to side. You’d need to sweep it with an analyzer or VNA to see and I don’t know if you have one. I’m very interested in what you discover. I’ve had ice build up on a wire antenna before. The SWR went through the roof. After the ice melted the SWR came back down slightly but I had to shorten the wire to move the dips back where I needed them.