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marcspaz

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marcspaz last won the day on December 7 2024

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  1. Yeah, we have had that happen around here a few times when a new machine was stood up. It sounds weird when its understandable.
  2. If the tones are the same, both repeaters would come up and 'repeat' your transmission at the same time. No loop could be created. If you set it to different tones, then the only issue to watch for is mistakenly causing interference. The users of each repeater would probably need to just transmitting a tone, but not using tone squelch. This way they can tell if the frequency is in use. Either that or they would need to 'monitor before transmit' if they have a monitor button on their radio.
  3. For what its worth, with both VHF and UHF, you can greatly extend communications well beyond the traditional LOS on the regular bases with the two stations involved being a bit 'over the top' for a typical Amateur or GMRS user. For example, if you have a 9 element or 11 element high-gain yagi on a 50' tower at both stations, you can reliably communicate 100+ miles with a 50w radio on VHF, and 60+ miles with a 50w radio on UHF / GMRS. If you happen to have your antenna somewhere comfortably above the average terrain, your station can talk even further. This is because the additional height above ground extends the LOS range a bit, but the magic is in the yagi antenna. Not only is the high-gain antenna able to pull more scattered energy out of the sky with greater efficiency, the fact that the beam is focused in a specific direction reduces the amount of random noise it pulls from the atmosphere. This allows the antenna to perform significantly better compared to a vertical antenna with the same gain as the yagi, for example. By reducing the total number of photons the antenna reacts to, you essentially improve the Part Per Million ratio in favor of the signal you are receiving. My radio club used this principle in combination with a propagation method called Sporadic-E (reflecting a signal off the E Layer) to talk over 1,500 miles on VHF, from Virginia to Texas. Our club had a stacked beam array and a 1,500w amplifier located on a mountain ridge in VA at 4,400+ feet and the Texas station had a similar setup in the western part of Texas, on a ridge line at about 6,000 feet. We were also running a UHF station with a similar configuration that same week. We contacted a station over 450 miles away. Though I don't remember the specifics of where the other station was for the UHF contact. Anyway, I guess the moral of the story is, while refraction off the ionosphere isn't an option for mid to upper VHF or UHF... if we get creative with location, antenna and available forecasts of atmospheric conditions, we can bend or even break the commonly accepted LOS rules with our base stations, control stations and fixed stations. We just need to leverage physics a little better.
  4. Are you talking about a "Current Choke" very specifically or are you talking about a "Common Mode Choke"? Many people use Current Choke and Common Mode Choke interchangeably. These are 2 of the 3 Common Mode chokes that I own... I also have a 100w LDG Current Balun for when I am in the field without the amp (it's not handy for a photo). I think with the ACOM 1010, the Palomar would be the best choice.
  5. Oh! That's good to know. I'm running an OCF 80m dipole, too. There is a balun at the antenna, but maybe I need one in the house? Maybe on the output of tuner? I have 2 of them that i use when portable, but didn't think about trying one at home. I can try a couple different spots and see what works best.
  6. I can't run more than 100w in any mode that I use my computer for radio control, because the RF messes with my computer. I think it's because of the USB cable, but im too lazy to go buy another one to test.
  7. Something I always found interesting is most VHF stations were using about 3kw ERP. Some UHF stations were 150kw ERP, but high-power stations were 500kw ERP. Between the higher power and shorter wavelengths, UHF always had better image quality compared to VHF. I remember dang near every house had a massive TV beam antenna on the roof and a rotator controller on top of the TV. We had a list of what direction to point the antenna to watch specific channels, and we would kind of fiddle with it to get it just right. But the best was if you had a set of TV top 'rabbit ears' and loop. I remember (before we got a beam) we weren't allowed to move around the living room while mom and dad were watching TV and we all had specific spots to sit when we watched TV, because our bodies would impact how well the TV signal were received. Or we would stand there touching the rabbit ears so grandpa could watch the news. LoL
  8. Yep... that is the site I use.
  9. The numbers I provided are the RF horizon. But, yes, typically the RF horizon is about 15% further than the visual horizon.
  10. In my opinion, it really depends on your expectations. 15 feet gets you about 5.5 miles to the RF horizon. 35 feet will get you out to about 8.5 miles. 50 feet gets you about 10 miles.
  11. Just putting my two cents in, and reiterating what others have said... in the world of handhelds, GMRS and Amateur Radio UHF perform the same since they are in the same band and general frequency space. Again, specifically with handhelds, the lower in frequency you go (VHF and HF for example) the worse the performance will be as the antenna becomes less and less efficient. This is because the lower in frequency you go, the longer the radio wave length will be and the longer the antenna needs to be. Now, if you were to take an HF handheld and hook it up to a standalone antenna system that is the proper size, then you can literally talk around the world. The drawback is, the handheld is really no longer 'portable' for all intents and purposes.
  12. Man... I remember when I first bought the TRASH80. So many people talk crap about it, but man did I have fun with that thing. I learned how to write shells and programs using that thing. Backup and restore to a cassette tape was too funny, too. Radio Shack was a great store for two-way radios all the way up to when computers, cell phones and satellite TV became mainstream. I literally bought components to do repairs if I had a customer waiting on a job and I ran out of resistors, capacitors and standard 3-leg transistors... occasionally ordering bulk ICs, and PAs for radios I was commonly repairing or upgrading. The good old days of peaking, opening up modulation, adding channels. Good times.
  13. Im just trying to help and little, but i think there is benefit to watching this video. I put it together for some new Hams in my club, but the Amateur frequencies in UHF are close enough to GMRS, that the demo is still very valid.
  14. How do we "loose" an attitude? And which one is it? Should we stop discussing this stuff or should we share our knowledge and experience? I'm confused.
  15. I've done exactly this. It was to demo real-world line loss at example frequencies. I'll share a link if you or anyone else is interested.
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