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SteveShannon

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Everything posted by SteveShannon

  1. It probably never could be perfected. With one PL tone locked out and hundreds others potentially being used, whenever one of the other tones is present, squelch is opened, allowing the strongest station to be heard.
  2. I’m not an authoritative source but I haven’t seen any GMRS radios that allow blocking a single tone. But apparently some scanners do allow a tone lockout: https://forums.radioreference.com/threads/sds-how-to-block-specific-dcs-ctcss-from-non-tone-protected-channel.414445/
  3. Network connection. Connection of a Personal Radio Services station to the public switched network, so that operators of other stations in that service are able to make (and optionally to receive) telephone calls through the connected station.
  4. After flip-flopping on this like a very lively fish, I have to agree with the logic and concern about poorly written rules expressed by 73Blazer. 95.349 covers all of the personal radio services. It prohibits connecting to the telephone network but allows exceptions in the rules for each service.. It doesn’t mention other types of networks. 95.1749 is the exception baked into the GMRS rules, but as 73Blazer says the exception listed there is poorly written. The phrase basically allows us to connect to the telephone network or any other network only for the purpose of remote operation. But connecting to any other network was never prohibited in 95.349 or the first clause of 1749, so I think the FCC’s interpretation under the Operations Tab on that other page is wrong. That might be what they want it to say, but wishes don’t make rules.
  5. That’s just fine. And don’t worry about desense on your RT97. Nobody has ever reported desensing the RT97 at factory power levels in this forum. Now if you started running an amplifier between the transmitter and the duplexer I could see it happening, but the RT97 actually consists of a completely separate transmitter and receiver. For your purposes it should be fine. Take your repeater and handhelds someplace clear and flat and see how much range you get.
  6. It says nothing about IP. It simply says other networks. There are many other kinds of networks. But I agree; any enforcement action must be based on the CFR. Many trials occur because of differences in interpretations.
  7. Absolutely 100% agreed. Here’s the actual paragraph: You can expect a communications range of one to twenty-five miles depending on station class, terrain and repeater use. You cannot directly interconnect a GMRS station with the telephone network or any other network for the purpose of carrying GMRS communications, but these networks can be used for remote control of repeater stations. It must be pointed out that that is the FCC’s interpretation (which counts! ) of 95.1749. I don’t have a dog in this fight. I don’t have a GMRS repeater and if I did I doubt that I would link it. I think it boils down to this, based on the definition of remote control, I can connect to a repeater and remotely control it via the Internet. But connecting one repeater to another repeater to carry traffic between them over the Internet goes too far for the FCC. But my understanding should not be taken as any kind of authoritative source.
  8. The phrase “or other networks” has been present in 95.1749 for years. Here’s a post from 2018 that quotes 1749:
  9. On the Airspy groups.io, there’s a post that includes the following advice: DO NOT use the local NOAA transmitter. While it may be on frequency, it could be off frequency by several kHz. DO NOT use the local FM Broadcast rock station transmitter. The frequency will deviate far off frequency. A talk station might be usable if you can hit it during a "silent period", but they are overall not recommended. There are better alternatives. https://groups.io/g/airspy/topic/69841361
  10. In Windows, you can either do the three key chord shift-window-s keys to bring up the snipping tool or you can use alt-prtscr or ctrl-keys.
  11. Now you’re off on a bit of a tangent, but I agree that a 10 dB increase is very significant.
  12. Referring back to what you said earlier: You talked about how a 5 watt radio with a 6 dB gain antenna puts out 20 watts ERP and a 10 watt radio with that same 6 dB antenna puts out 40 watts ERP. You talked about how that gain compounded. You’re exactly right, but just as the difference between a 5 watt radio and a 10 watt radio is only 1/2 S-unit, the difference between 20 watts ERP and 40 watts ERP is still only a half S-meter unit. But adding the antenna made a full S-unit difference for both radios, if you’re in the direction of the 6dB gain. That’s an audible difference. Half of an S-unit may or may not be subjectively distinguishable to a human ear. One S-unit is audibly different, even though it’s four times the power. But I wouldn’t consider it very significant. Two S-units would be very significant, in my personal scale of significance. S-units provide us something that is objectively quantifiable, but whether something is significant or very significant is subjective. You may feel that one S-unit is very significant.
  13. What makes you think that your VFO is more accurate than theirs? Maybe you’re off by 257 Hertz. I think all upper end HF receivers have a “Clarifier” adjustment to adjust for the many radios that don’t exactly match their frequency. I tune to an integer kHz and then adjust the clarifier, with the assumption that my VFO is perfect. Transmissions from satellites require a Doppler shift that varies based on orbital velocity and whether they’re approaching or moving away. Are FM transmissions modulated symmetrically about a center frequency, or do they modulate in one direction from the carrier? I don’t know.
  14. I’m sorry you’re confused. I don’t think my statement (quoted above) is confusing, but maybe I made it too terse. Doubling power, with no other changes, results in a difference of 1/2 S unit. That’s by definition - one S-unit represents a difference of 6 dB, which is 4 times the power. That’s substantial but when you’re sitting in front of a radio it’s sometimes difficult to quantify. Making other changes (such as antennas) are more likely to result in changes as measured by the S-meter.
  15. Broadcast radio stations are also stereo. They can’t be directly compared to a monaural FM GMRS signal.
  16. Go ahead and use it for awhile. The difference between your radio and the 935g will be in little features that might make things more enjoyable. Otherwise they’ll probably talk just as far as each other. I would recommend going to a radio club somewhere so you can get your hands on some different models. You might find that the things that irritate you grow on you.
  17. How can you tell? TSQL on 26 and no tones on 18?
  18. I have and in a very short period of time. But mostly with antennas that get moved around from one vehicle to another Over time they pick up pieces of magnetic grit or even steel shavings and grind them into the clear coat and eventually the underlying paint. It’s very important to make sure the protective boot and the car roof are completely clean before attaching the antenna and a layer of clear protective film is really helpful.
  19. What were the SWR values and did you measure at both the 462 and 467 MHz frequencies?
  20. I’m interested in hearing how you like it.
  21. Technically, you should pronounce each character, but realistically, for GMRS nobody cares. The fact that you even attempt to ID is better than most people do.
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