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SteveShannon

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Everything posted by SteveShannon

  1. The OP lives in Lyman, which is well outside of Line A. Does the MyGMRS repeater map display Line A? No - that might be a good suggestion though.
  2. There’s no reason to expect different results for plexiglass than you experience with glass. I would expect identical results. Of course it’s relatively easy to just drill through the plexiglass or clamp the mount to a roll bar. Best wishes as you work through this traumatic experience. More importantly make sure you use an antenna that doesn’t rely on a ground plane.
  3. Become a ham and buy a mobile that incorporates GPS and APRS.
  4. Yes, so it won’t be left on top of a car by someone who’s not worthy of a good radio.
  5. I know, right? Just google PicoAPRS.
  6. Nice, but this is real and does APRS:
  7. Thank you! I’ll try to expand on it. I haven’t seen an FAQ.
  8. And there’s nothing wrong with that.
  9. Maybe, but you weren’t specific enough. The repeater’s Output is its TX but is heard on your radio’s RX. Similarly, your radio’s TX frequency or TX tone, must match the repeater’s Input frequency and tone. Your radio transmits at 467.xxx MHz to the repeater. The repeater transmits at 462.xxx to anyone listening. There are only eight 467/462 repeater frequency pairs. Those frequencies are established by the FCC rules. Nearly all repeaters require a tone, otherwise they would be re-transmitting everything they receive. Your radio transmits a specific tone (CTCSS or PL, they’re two names for the same thing) or digital pattern (DTCSS or DCS or DPL) to open the repeater. That’s called the input or uplink or even receive tone for the repeater. The repeater usually sends a tone or digital pattern along with its transmissions. That’s the output or downlink or transmit tone of the repeater. Those terms are standardized so we can share information. The repeater output tone is for your convenience to lessen interruptions, but it doesn’t provide any kind of security. There are only eight frequencies that repeaters can receive on and only eight that they can transmit on. The frequencies that repeaters transmit on are the same as people use for simplex communications as well. If you are within range of a couple of repeaters that receive and transmit on the same frequencies, using different tones can ensure that your transmissions are being repeated by the correct one and that you’re hearing the correct one. So, for example, repeater Sandhawk and repeater Black Brant both receive on 467.550 MHz and transmit on 462.550 MHz. They’re far enough apart that they don’t usually bother each other, but you happen to live where you receive them both. Sandhawk uses an uplink or input tone of 67.5 Hz. That means that you MUST set your transmit or TX tone to 67.5 Hz or Sandhawk will just disregard your transmissions. Sandhawk uses a different tone, 100 Hz, for its output tone. Using two different tones for TX and RX is referred to as having a “split tone”. It’s usually done by repeater operators who want to protect against unauthorized access to their repeaters. Why? Because it’s easy to scan for the repeater output tone. It’s not as easy to scan for the input tone. The Black Brant repeater uses 103.5 Hz for both input and output. What a lot of people don’t initially understand is that these tones work like filters. If I set my handheld radio to a receive tone of 103.5 Hz my radio will only break squelch when it receives a transmission that incorporates that tone, which would be the Black Brant repeater. If I set my radio receive tone to 100 Hz it will only reproduce transmissions it receives which include a 100 Hz tone. But, if I don’t set a receive tone in my radio, it does no filtering. It literally reproduces everything that has a signal strength sufficient to break squelch. That’s useful, especially when trying to troubleshoot. Don’t fall into the trap of referring to a tone by a number or some other shorthand because not all radios number the codes the same. Always refer to the frequency of the tone, such as 103.5 Hz, or the DCS code. Not all radios include all the tones. Motorola and Midland include the standard tones, but fail to include some of the tones included in the overseas brands. Thus they might not be able to access some repeaters.
  10. I’m with you. Give your loved ones good quality items. They’ll appreciate the fact that you care. A person’s life generally sucks if they go through it having such poor faith in their loved ones that they only trust them with the cheapest of things because they just know they’re going to lose them or break them. “Honey, you’re just going to get scratches in it anyway so I’m getting you a gold plated ring rather than 14 karat.”
  11. I haven’t heard of any mobiles that violate that particular rule. How would they be certified?
  12. Visqueen keeps the fines out! I sure don’t blame you for being pissed. I’m glad things were no worse.
  13. The range probably won’t change much , but if you like the features of the 500, go for it. There is a certain psychological comfort in knowing that you have the maximum allowed power, though.
  14. Yeah, Pasternak has every kind of connector ever made, but their pricing is extremely high. I use them as a reference only.
  15. DXengineering will assemble cable to any length. There’s no point in buying and using a 50 foot cable if 10 feet will just be coiled up somewhere. Ham Radio Outlet, DX Engineering, and Gigaparts all have sales to mark the Huntsville Hamfest. They all have good quality cable and probably carry Times Microwave. For long cable I use Messi and Paloni 10 mm. They have a few different types. All are good. Most have stranded copper center conductors, except for Airborne, which uses copper clad aluminum center conductor for weight. True LMR400 uses a copper clad aluminum center conductor and copper braid over aluminum foil as it’s shield. M&P uses copper braid over copper foil for shield. True LMR400 comes from Times Microwave. I also have jumpers from ABR400. Buytwowayradios.com has good pricing for M&P cable and a good assortment. For whatever reason Gigaparts has a lot of “out of stock” selections for M&P.
  16. I recommend watching Notarubicon videos on YouTube. I wouldn’t go high end at first; I would buy something low to mid level and play around with it to learn what features are important to you. Nobody buys just one.
  17. Welcome! Feel free to ask questions.
  18. Let’s say you have 30 watts at the SO-239 on the radio. Then you have the impedance mismatch so a certain amount is reflected back into the radio. That leaves 20 watts going in the direction of the antenna. Then you have a loss of 1.7 dB, which is about 30% of the 20 watts that’s lost. So you’re down to about 12 watts. I’m estimating rather than calculating so these are pretty sloppy numbers. You don’t say whether the antenna gain is dBi or dBd. Assuming the best you’ll have about the same RF in certain directions as 25 watts in an isentropic antenna (it really is only 12 watts, but in some directions the RF field will be as strong as a 25 watt signal into an antenna with no gain.
  19. I’m relieved to hear that. My brother-in-law lives in San Clemente. I’m hopeful the storm leaves him and his wife alone.
  20. Unfortunately these two sentences pass along bad information. I’ll take them separately: Yes, it’s generally best to use feedline that matches the impedance of the radio, but swapping a minor impedance mismatch has fewer disadvantages than using RG-58 or 58x which has incredibly high attenuation at GMRS frequencies. Using 75 ohm feedline with a 50 ohm radio simply means that you start with a theoretical SWR of 1.5. That’s not terrible and PL-259 connectors are available for both of the common 75 ohm cables. So are adapters. RG-11 attenuates RF in the 400 MHz range at the rate of 3.5 dB per 100 feet. That’s a little more than half of your power lost in the cable. RG-58 attenuates RF in the 400 MHz range at the rate of 11.2 dB. That’s more than 90% of your power lost. I wouldn’t use RG-58 for GMRS feedline for anything longer than 10 feet. https://www.w4rp.com/ref/coax.html
  21. Probably a dozen. Nearly everyone I know who gets radios for their kids or themselves (but are not hams) goes to the nearest sporting goods store or Walmart and buys a pair of Midland or Motorola (or no-name) radios in the heat sealed blister pegboard packs. There are four of us who graduated to Garmin for the GPS, which we buy at Cabelas. I probably have four of the bubble pack radios in my rocket trailer now that people have donated. I have yet to see someone show up with a Wouxun, but I do see a few UV5R radios that folks order from Amazon. I also see people buying blister packs at truck stops. I would guess that those are the ones that end up on construction sites. What is it you think we would be less than honest about?
  22. The PL tones only reduce the probability of interruption. They were never designed to protect your transmissions. But the use of the word Privacy was misleading.
  23. Actually there’s nothing wrong with you transmitting to the repeater and listening on your UV5R. It’s totally within the rules and if anyone tells you otherwise they’re full of it. But transmitting on one radio and listening on another right next to it doesn’t always work because the receiving radio “desenses”, which means it is swamped by the stronger signal and fails to reproduce it. That’s especially true for inexpensive radios.
  24. @JamesBrox The fact that you are hearing a transmission doesn’t mean it’s in the open. It may simply mean that you have no receive tone set on your radio. If that’s the case you will hear everything, whether it is sent using PL tones or not.
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