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KAF6045

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Everything posted by KAF6045

  1. Ignore... content was badly superseded by other posters
  2. That may be possible to fine-tune once you get the lengths into the GMRS range. Doing a frequency sweep with a UHF capable antenna analyzer (or VNA which tends to do sweeps automatically, rather than requiring one to slowly turn a knob) would show you where the SWR is lowest. From that frequency it may be possible to compute how much needs to be removed (it's simple for true dipoles, but when you have unbalanced legs or loading coils it falls apart somewhat https://www.hamuniverse.com/easydipole.html )
  3. As mentioned by others -- if you have enough GMRS licensees (remember, the license covers "immediate" family members, so if your group has such...), stick with the GMRS radios. FRS radios compliant with the 2017 reorganization will approach 2W on 1-7 and 15-22. 8-14 is restricted to 0.5W ERP as they are splitting the GMRS repeater INPUT frequencies (1-7 split the GMRS output frequencies, but were also GMRS interstitials BEFORE FRS ever existed -- GMRS is allowed up to 5W on channels 1-7). A "proper" FRS will NOT have access to repeater inputs (23-30; aka rp15-rp22 and variations thereof). I'd have to question the selection of channel 18 if using FRS radios in the mix -- that just smells of potentially interfering with repeater outputs. I'd probably stick with 1-7 as they are simplex only. I'd tend to "save" 15-22 for GMRS units that might be reaching repeater (of course, if there are no repeaters [open or closed] within miles of the locale, go ahead with that range). If you do have FRS and GMRS in the mix, and if the GMRS radios have a medium power (or just are weak -- as both my BTech HTs are; just over 2W even though the V2 is supposed to be 5W -- the V1 was only 2W to start with), I'd suggest using medium (or whatever is near 2W) just to equalize the reach between FRS and GMRS units. At the least, it should extend battery life a bit on the GMRS stuff.
  4. And after the SWR meter, there are full-up antenna analyzers... Many of those can even give estimates of "distance to [short/open]", without needing a radio or antenna connected.
  5. ... and if maintenance is all one needs it for the GROL would be the one to study/obtain.
  6. Short of building a model in some antenna evaluation software (or putting the unit on a test range), anything goes. My expectation is that it will "wobble" the horizontal pattern some, reducing it in some directions while extending it in others. There is a reason so many truckers used phased duals (left&right mirror mounts) for CB -- the pattern tends to extend in the direction of greatest metal mass, so with a big trailer behind, much of the signal went to the rear and the rest forward. The phased pair could help direct a bit more to the sides for a circular pattern (even free ways aren't completely straight).
  7. The archaic (23 years) FT-100D*, with an ATAS antenna, covered HF/6m/2m/70cm with 100W on HF/6m, 50W on 2m, 20W on 70cm. If band conditions are good it could receive out-of-state HF signals while in motion -- I'll confess I don't know if the antenna was sufficient to reach back to those signals (I was less than a mile from work and didn't want to break into the on-going conversation. This was during the last solar cycle peak... 14.300 net tends to have "big operators" so might have been usable, 10m opening I'm not certain of). * Don't know if the unit fully survived the roll-over in my Jeep Cherokee of two years ago (only 6 months older than the Yaesu unit) -- the ATAS needs a new stinger and I don't know if the screwdriver is stripped, as the retracted length put it just past the top of the roof line. Replacement rust bucket got an ICOM 5100.
  8. It's the whole "being over an hour offset from the sun"* that bothers me. Solar "noon" is happening at 11AM! If I owned a small business, I'd implement different hours in DST than in standard time. That is, the opening hours of the business would also "spring ahead" (standard time: 10am-6pm, say; DST: 11am-7pm) * I emphasize "over" as the span of a standard time zone can be +/- 30 minutes solar difference at the boundaries, the sun is at zenith only at the central meridian of the time zone. Which means under DST the sun can be at zenith up to 90 minutes off...
  9. "Picket fencing" is sort of a doppler effect from the antenna moving around (unless one is driving past a really tall metallic picket fence ? ) -- nothing that can really be adjusted by the grounding status. You placed the antenna on top of a tall thin stick -- both the stick and the antenna are going to flex under wind and motion. The suggested roof mount takes out the tall stick.
  10. Most units that exceed 50W on VHF will be HF/6/2m/70cm rigs -- mostly desktop stations, not mobiles (the discontinued Kenwood TS-2000 did come with a mobile mounting bracket, but you'll either need a camper-van conversion to mount it in the back, or rip out the front the passenger seat as the unit is the size of the seat cushion). Even then, the 70cm (UHF) output is typically 50-80% that of the 2m (VHF) output [50W vs 100W, 40W vs 50W] -- and there is no assurance that 2m operates at 100W. 100W tends to be reserved for the HF/6m range.
  11. If one is mostly in a receive mode, it probably will not be overly critical... But it is a common situation that transmitting consumes two to three times the electrical power relative to the output power. IOWs, a 50W transmitter is consuming 100-150W of electricity -- and the excess (50-100W) is released as heat. Think of a 100W incandescent light bulb (do they still sell such things?) -- that's the heat source of an old "Easy-Bake" oven! That's the heat you want to dissipate.
  12. As mentioned, it is /now/ just a list of specific relationships. One could allow children residing in college dorms across the state to operate under one's license (but since one is also responsible for /correct/ operation, I wouldn't recommend such unmonitored permission). In the past (say, the 1990s) the restriction was for same household -- think large family farm with a base station (maybe tied to a repeater) and family members in the fields with (tractor mounted) mobiles and/or HTs.
  13. Not sure if I should take that seriously, or as a joke... "Turnstile" is, as I recall, a twisted, circular polarized antenna
  14. No... ALL Stations MUST ID -- a repeater is a station. There is an specific EXCLUSION for what is a private/family-only repeater, since the repeater ID would be identical to the ID used by all family members (that of the license holder). Paragraph (c) was quoted previously.
  15. For comparison, a half-wave vertical dipole -- no ground plane required -- is twice as long as a quarter-wave vertical -- ground plane needed. That makes for more antenna sticking up to be hit by tree branches if off-road, parking garages, etc.
  16. The Technician license is focused on regulations with just a touch of theory. This is to ensure you don't cause interference with others or misuse the privileges. You get more radio theory/practice (circuits) at the General level, and a lot more at Extra level exam. I started as a "no-good" (no-code) Tech when they created the VHF/UHF-only option decades ago. Lockheed (Sunnyvale) radio club had their own repeater, and membership to get auto-patch (telephone linking) was much cheaper than a cell-phone at the time. When they finally dropped the code requirement a decade or so ago, I spent two weeks with a General class study guide. Found an on-line practice test site. Was passing all tries with 90% scores. Tried (without study) the Extra class practice exams, and managed to pass about 3 of every 4 I did. So -- that weekend I drove up the Bay area to a license session and took both tests. I felt that if I didn't pass Extra, I could study for two weeks and get the next exam session down where I lived. Passed Extra by 1 question. There are post-2017 radios that are also NFM only... But these radios will be marked as FRS (the 2017 reorganization banned radios marked FRS/GMRS, and gave FRS the typical power of pre-2017 dual-marked bubble pack radios). My recommendation was to remove the FRS NFM config UNLESS you have a lot of associates who are using FRS radios. If most are using licensed GMRS, stick with FM setting and put up with the slight audio quality mis-match for the rare FRS user. Technically -- there is NO privacy for GMRS/MURS/FRS/Amateur. Setting a tone only controls who YOU HEAR (they have to be sending the same tone). Anyone with a radio that has no tones set will hear /everything/ on the frequency. "PL" ("Private Line") is Motorola marketing speak. To the rest of the world it is just CTCSS (Continuous Tone Coded Squelch System -- though newer systems also support Digital Coded Squelch). Granted, many radio programming software separates it as "CT" (send a tone) and "CTCSS" (send and receive tone). Skip is for scanning purposes -- it says "skip this channel when scanning" Offset is for repeaters. For GMRS it is supposed to be +5.0MHz (listen on 462, transmit on 467) Cross mode is a confusing entry -- depending upon the programming software. Some radios can be configured to use CTCSS tone in one direction and DTC tone in the other. As I recall, in CHIRP, "TONE" means SEND-only, "TONE SQUELCH" is SEND/RECEIVE. And to confuse matters, CHIRP uses different columns for the tone specification itself (my Amateur gear, OTOH, doesn't require first selecting mode, then picking tone -- just encode/decode [send/receive] tone columns, and if that column is set to "None" then no tone is used for that side).
  17. I wouldn't expect trunking systems to need such. Cell phone towers perform triangulation (especially in the days before every phone had GPS capability) to optimize signals to phones, so having an array provides TDOA capability.
  18. https://mfjenterprises.com/products/eve-48 Also get a decent mast -- don't try electrical conduit...
  19. 8 miles is close to radio horizon unless you can mount the antenna really high. Radio horizon for an antenna at 30 feet is 7 miles.
  20. Remove any piggyback boards, download a recent RaspOS image and burn to a new SD card. See if that boots? Note: recommend using the R-Pi installer for this, as it has a series of pages to configure username/password (the old default is no longer created on image burn), set up WiFi, enable SSH, etc. If this won't boot, consider that board possibly dead.
  21. Note that in your screen image, the only difference between the "FRS 1-7" and "GMRS 1-7" is the difference between NFM and FM bandwidth. 8-14 are IDENTICAL -- 0.5W ERP NFM. GMRS is permitted up to 5W on 1-7, and up to 50W on 14-22 (and repeater pairs); true FRS is limited to 2W NFM on 1-7/15-22 (and NO repeaters). If the radio can exceed 2W on any channel, or access repeaters, that radio is classified as a GMRS radio. Oh, and FRS-only radios are license free, GMRS requires a license. The only justification (in my mind) for duplicating the FRS NFM config is that you have a lot of associates using old (pre-2017 "FRS/GMRS") radios with NFM only. Otherwise I'd just strip out the FRS configuration and stick with GMRS FM (remember 8-14 are low power NFM in both services).
  22. 10-codes (both CB and Law Enforcement variations) are commonly available in printed form, everyone can access the list(s); they are not considered a means of "obscuring" communications but are a means of /shortening/ the time spent in communications and providing a concise /clear/ meaning (especially when one has an atrocious accent and spoken English may be misunderstood). Not that English is mandated either -- I believe only the call sign ID needs to be in English or recognized phonetic alphabet (so keep your "zed" down under ).
  23. What is the roof itself made of? Are there any metal conduits/duct-work nearby (especially the latter -- you can probably avoid conduits okay)? I basically am living in a Faraday cage -- metal roof and aluminum siding.
  24. You could... and possibly rile up the repeater owner/group such that they decide it isn't worth running the repeater anymore and they take it down. Ability to do tone scanning is a somewhat recent feature on radios, older equipment won't have it. I think I only have one radio that does tone scanning, out of five GMRS radios. Don't recall ever seeing (or, at least, using) tone scanning on any of my Amateur radios (heck, the oldest ones don't even have tone decode, only encode! Tone decode required $$$ modules to be installed))
  25. Bandwidth is the amount of space a single /signal/ is allowed to take up. The MXT-115 uses 12.5kHz NFM -- the same bandwidth as FRS. GMRS is authorized 20kHz (though most rigs these days tend to bluff it at 25kHz -- especially as the modulation mode tends to be 16k, vs 11k for narrowband). It makes for a difference in the audio quality going between the two bandwidths (regular FM will be clipped by an NFM receiver, while an NFM signal won't be using the full dynamics of an FM receiver).
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