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OldRadioGuy

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OldRadioGuy last won the day on October 9 2021

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  1. There is one situation where PL tones work pretty much like people want them to. If I'm on my 2 acres talking with my family on one PL tone and another family a mile down the road is on their 2 acres using a different PL tone on the same channel it will behave pretty much like our two families are on different channels. The signals within our family groups are strong enough to overwhelm the signals from the other family and the PL tones block us from hearing each other. Back when businesses used GMRS/FRS it would work OK. The gas station and hardware store down the street could have their own conversations without getting all mixed up. Of course any listener who turns off their privacy tones will hear everything said on that channel. So it is only a voluntary privacy. I always leave the tones off because I want to know if the channel is being used... but we don't live in a busy area. I suppose turning on XMIT tones only might give you some privacy while allowing you to hear other traffic on the channel. Vince
  2. I had a good case of ducting once back in Nov. of 1986. I had just moved to my new house in Greenfield (southern NH) and put on the portable TV to test the signal. I was relieved that I was still getting the Boston MA and Manchester NH channels OK - but there was another rock solid channel that I was not familiar with. I watched for a while and it turned out the be Burlington, VT which was shocking. That's 160 road miles away with mountains in between. It just didn't seem possible but there it was - rock solid. I had only moved about 20 miles further up from my old place in Milford NH. I'd never heard of anyone getting Burlington TV around southern NH. It was not a TV repeater channel either. It was the Burlington channel direct. It was probably 9 or 10pm at night. The next morning I tried it again and it was nowhere to be found. Tried it a dozen more times and nothing but blank screen. It was just a case of ducting that came and went. Vince
  3. Yep, Mbrun is right, but you may need a lot more than 100'. Try getting something metal (vehicle, metal shed) between you and the nearby transmitting radio. You may also try using lower xmit power if that's an option on your radio. It's a common problem. Vince
  4. In hilly places like VT repeaters are necessary to get much range. So HAM is going to get you much better service than GMRS unless you happen to be in an area with a GMRS repeater..... which is unlikely. See repeaterbook.com for listings of HAM repeaters in your areas of interest. Also, with HAM you have other freq. choices that can be very helpful. VT is very wooded and snow gets on the trees which tends to eat up higher frequencies. So 2 meters or 144 MHz can be a better alternative. GMRS is great for reaching your fishing buddies or other nearby but longer ranges are very dependent on repeaters. I have GMRS because my wife and fishing buddies can't use HAM radio. So it has its place. I lived in NH for some of my HAM years and (30 years ago) repeaters were quite good. I was often able to reach people with 5W and a mag mount. There were "ham-fests" in VT and more hams than you'd think. I expect that there are still some HAM clubs around VT. This is the best way to get started. Today the issue can be finding a live person on the repeater. But if something was "going on" I'm sure there would be lots of hams on there. Vince
  5. Transmitting with no load is a very different thing depending on the length of coax connected to the radio. An open circuit plus 1/4 wavelength of coax equals a short circuit. Any odd number of 1/4 wavelengths will look like a short. So the load seen by the transmitter can vary a great deal. Some lengths could possibly make the transmitter unstable causing it to oscillate at some other frequency. But this is somewhat less likely in newer radios where device parasitics are much lower today. But it's still possible. Note: 1/4 wave at 460MHz is about 5 inches. Remember that wavelengths are shorter in coax than in free air. You have to multiply by the velocity factor for the particular coax.... usually around 65-75%. When there is nothing connected to an HT it's likely to look like an open circuit since the transmitter circuits are likely very close to the connector. So this would be one of the safer no-load conditions. I suppose the worst case would be an apparent short circuit that may cause overcurrent but today's transistors are much more rugged than the ones of the 1970's. And, since your radio probably uses a switching power converter it's unlikely to provide enough current to cause any damage. Of course we are talking about hand held radios here. I would not key a transmitter intentionally into an unknown load but I would not worry about doing it unintentionally for a short period of time. It certainly can happen for a variety of reasons, like forgetting to replace the antenna after a car wash or something. Most legitimate radio designs would handle this fine. Designers are aware that this happens.
  6. Stainless steel is very compatible with brass and nickel plating. (Of course gold is inert so no worries there.) So you'd be fine using stainless. Stainless gets along pretty well with aluminum too if there's any of that involved.
  7. As the others have said it makes a huge difference. The biggest problem can be the strain on the connector from the heavier cable. It's often good to put a right angle connector (or two) at the radio. Ham Radio Outlet sells "pigtail" adapters with a short length of thin, flexible coax. Another idea is to use a speaker mic so you are not trying to drag that antenna cable around. Powerwerx has a good speaker mic for cheap that works on KG805's. Pasternack sells custom cables if you want to make your own custom flexible adapter cable. RG316 or RG174 are nice thin coax cables for a short length. Vince
  8. I can see that you are just a troll so I'll move on. The "maths" speak for themselves.
  9. For those of you who don't believe it... let's do the 1/4 wavelength calculation. 300/(462MHz x 4) = 162.3mm low channels 300/(467MHz x 4) = 160.6mm repeater channels (162.3-160.6)/162.3 x 100 = 1.04% Looks like the math is linear enough. Vince
  10. Antennas are never a full wavelength so N/A. Most simple vertical antennas are 1/4 wavelength. And it's spelled HERTZ not hurts. Vince
  11. 5/462 MHz x 100 = 1% (rounded off) The difference between the "lower channels" and the repeater channels is 5MHz. Vince
  12. I have the "surveillance" style headset (for Wouxun 805G) from Buytwowayradios and the vox function does not work very well. We did not fiddle with it too much but never really got it to work the way we'd like. I'd like to try our speaker mics on vox and see if that works any better. Our speaker mics are from Powerwerx and they seem very nice for the low price. You can clip it on your collar or hang it on a neck cord. Vince
  13. The frequency difference we are talking about here is 1%. So, would you want to shorten the antenna 1% ???? (rhetorical question, of course you wouldn't) I just wonder if something else is going on. Unless it's a very short antenna with a very narrowband match. It just doesn't make sense. Maybe the meter is the problem. CAn you try a different meter and cables? Vince
  14. Why don't you get a Ham license? They have a lot more repeaters in most areas. I have both and they both have their place. Vince
  15. Maybe I missed it but I don't think anybody mentioned SSB CB radio. SSB is 4x(?) more efficient than AM and also uses much less bandwidth so lower noise - if the filters are done right. It is still a form of amplitude modulation so there is more static than FM. But AM fades more gracefully than FM which tends to be "all or nothing". Sometimes on AM you can make out a very weak signal that would not be captured by FM. The longer wavelength will handle terrain better but the antenna also needs to be much longer. It's pretty hard to put a number on all the differences. Vince
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