Posted: 9/8/2012 8:52:42 PM EDT
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My dad has a Yaesu 2800 and is trying to talk to a repeater about 25 miles away. He has a Diamond 22 which is a 9 foot vertical that is about 25 feet above the surrounding terrain. Transmitting sounds great, but receiving is terrible. The only problem that I can think of is the coax. he has 40-50 feel of Rg-58 and I don't think it was weatherized properly. I assume the problem is that he can pump enough power up the line to transmit, but it cannot pull enough down other way. Does this sound possible, or is there another explanation? He can talk to a local repeater that is 5-6 miles just fine, it is the longer distance that is creating a RX problem. Ideas? *** Update *** So, we ordered some LMR-240 and installed it last night. The system now works 100x better. We can talk simplex over 25 miles with only a tiny bit of static. Turns out it was the coax. Thanks for all of the suggestions. |
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he has 40-50 feel of Rg-58 and I don't think it was weatherized properly.
50 feet of RG-8X has a loss of about 2.043 dB, while 50 feet of RG-58 has a loss of about 2.521 dB. An extra half decibel of loss doesn't explain his situation. Waterlogged coax perhaps? What happens when you swap his radio with a known good radio? |
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Thanks for the replies. I am looking at getting at least some LMR-240 to run because there are several twists and turns along the coax route. I have LMR-400 on my setup and I do not think that will be flexible enough for his setup. That will cut his loss from just over 5.5 to about 2.75 db. Thanks! |
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I don't think 3 db. difference in coax loss will make such a significant difference.I don't know the details about your terrain and repeater location. We can hit several repeaters located 20-30 miles away with a 5 watt handie talkie with a tiny antenna.
Sounds like your coax or the antenna connectors are damaged or corroded. Check the coax continuity with a multimeter. There may be a bad solder connection. Coax ends must be weather proofed. Water in a coax cable may cause all kinds of problems. A simple SWR check may be very beneficial. You antenna may not be tuned properly. |
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Quoted: I don't think 3 db. difference in coax loss will make such a significant difference.I don't know the details about your terrain and repeater location. We can hit several repeaters located 20-30 miles away with a 5 watt handie talkie with a tiny antenna. Sounds like your coax or the antenna connectors are damaged or corroded. Check the coax continuity with a multimeter. There may be a bad solder connection. Coax ends must be weather proofed. Water in a coax cable may cause all kinds of problems. A simple SWR check may be very beneficial. You antenna may not be tuned properly. Thanks. I am REALLY thinking it is the coax. He had a small cheap beam on the roof that would not do anything. A mobile base did better than that thing. We replaced it with the vertical, and now he can broadcast like a champ, but with tons of static on the RX. We will replace the coax this weekend, then see what happens. |
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Quoted: What is your dad powering his radio with? Try running off a battery to see if the problem goes away. Does the radio pick up the weather channels ok? He has an astra 25A switcher for base ops. No batts. Also, I just called him and the WX stations come in 100% clear. I guess because they are so high powered? |