Jump to content

Lscott

Members
 View Profile  See their activity

  • Posts

    3566

  • Joined

  • Last visited

  • Days Won

    105

 Content Type 

Everything posted by Lscott

  1. Lscott
    The government claims they don’t have an “off switch” for the cellphone system. Anybody believe that? I don’t.
  2. Lscott
    I was just looking at an "untested for parts or repair" RFC 4-110 UHF amp on eBay. It's 10 watts in and 100 watts out. I have one now and was looking at maybe picking up another one I could use with a UHF power splitter/combiner to get 200 watts. I would need two identical amps to equalize the phase delay on each path for the power splitter/combiner to work effectively.
  3. Lscott
    If you have any local malls within a few miles you might pickup the mall security, assuming they are on FM some are using NXDN or DMR by me, for entertainment. At times you hear some weird stuff. I've monitored reports of food fights in the food court, kicking hookers out of the mall, adult activity in back seats of cars in the lot, running down shoplifters, vehicle repo people with computer controlled license plate scanning cameras driving through the lots etc. They even kicked some local TV news crews off the property because they didn't get prior clearance. It gets much more active near Xmas. A few times some people were "asked" to put certain unnamed items back in their car, at least they didn't call the local PD on them, because it was prohibited to have them in the mall. I'll leave it to others to figure out what those were.
  4. Lscott
    Well until they figure out that much power won't get them much beyond the radio horizon. No "channel 6 super bowl" on GMRS. Also UHF amps that can do 250 watts won't be cheap either, if you can find them.
  5. Lscott
    Just a bit more studying and taking some practice exams you'll get there. It doesn't matter if you pass by one question or get 100%. Once you have it you're done.
  6. Lscott
    Because the license fee was cheap, now good for 10 years, sort of cool to have and goes along with my Ham license. One other factor it’s not much trouble to get friends and family to get the license since no testing is required. Just fill out some forms and pay the fee.
  7. Lscott

    GRMS Needed?

    Lscott replied to a topic in Guest Forum

    If you don't think you need it then why are you here?
  8. Lscott
    Perhaps the FCC sees GMRS evolving into a "Ham Lite" type of service as a hobby rather than a personal use utility communication service.
  9. Lscott
    I did find the following on the NR-770 antenna. worth reading. https://www.hamradio.me/antennas/diamond-antenna-nr770hbnmo-with-k515snmo-mobile-antenna-review.html
  10. Lscott
    What kind of match did you get on the Diamond? The NR-770 and the SBB-5 look like a clone of the other one. Might even come off the same assembly line with a different label?
  11. Lscott
    For testing I’ve used a section of sheet metal about 36 to 40 inches square from the local hardware store specifically to simulate a ground plane when using a magnet mount. This way I don’t need to drag crap outside for testing. I can do it in the basement. The sheet metal section is about the area of a passenger vehicle roof. It’s big enough for a VHF through UHF antenna. https://forums.mygmrs.com/gallery/image/306-220-mhz-antenna-scan/?context=new I’ve also used some brass rods bent at a 45 degree angle for a cheap home made ground radial kit. The rods were held in place using a stainless steel hose clamp around a short SO-239 barrel adapter. My antennas are typically using a UHF mount. https://forums.mygmrs.com/gallery/image/268-ca-2x4sr/
  12. Lscott
    Thanks for everyone who responded. I might pick one of these up to experiment with it. The SWR numbers look encouraging.
  13. Lscott
    What kind of SWR do you get with the SBB-5 antenna on the Ham bands, MURS and GMRS? I'm still looking for a 1/2 wave ground independent antenna I can use for Ham, MURS and GMRS. I need something that will work on my luggage roof rack rail mount. The CA-2x4SR is a 5/8 wave design which requires a GOOD ground plane, which I don't have with the mount I'm using. https://forums.mygmrs.com/gallery/image/473-close-up-of-mobile-mount/?context=new https://forums.mygmrs.com/gallery/image/471-mobile-mount-with-antenna-rear-view/ https://forums.mygmrs.com/gallery/image/472-mobile-antenna-install-side-view/ Old installation on my Jeep. https://forums.mygmrs.com/gallery/image/259-ca-2x4mb-jeepjpg/ https://forums.mygmrs.com/gallery/image/282-ca-2x4mb-scansjpg/
  14. Lscott
    While not mounted on a travel trailer it is a portable antenna and mast system. https://forums.mygmrs.com/gallery/image/257-portable-mast-antenna-system/ This is compact enough to pack in the back of a small SUV.
  15. Lscott
    There are several license free radio services in the European Union, PMR446 (narrow band FM), Digital PMR446 (DMR Tier-1), dPMR446 (dPMR). These all operate from 446.0MHz to 446.2MHz. The Ham band there is only from 430MHz to 440MHz so it's outside of their segment but within ours in the US. The licensed power is only 0.5 watts like our old FRS standard. I would suspect hearing them around popular tourist destinations for international visitors. They likely would bring their radios with them unaware they would be operating in the middle of the US Ham band. There is a forum where EU radio use is discussed. Some of the old posts are fun to read. https://transmission1.net/viewforum.php?f=4&sid=a74e04a3a9d842dce32abec0669cc532 PMR446 White Paper.pdf
  16. Lscott
    Yes to both questions. You can start off with a cheap 1/4 wave magnet mount. The antenna will only be about 6 to 8 inches tall depending on the exact magnet mount used. The antenna will be short enough where you likely won’t have to worry about clearance issues parking in a garage, going through drive throughs etc. This will at least give you an idea of potential improvements with a better external antenna. https://forums.mygmrs.com/gallery/image/338-cheap-14-wave-gmrs-antenna/?context=new
  17. Lscott
    You can get a reasonable estimate for the SWR at the antenna end of the cable if you know the coax losses, from a chart of loss verses frequency for a known length of cable, and the forward and reflected power. You can calculate the loss for the exact cable length one is using at the frequency of interest. The cable loss allows one to calculate the power delivered to the antenna based on the forward power measured at the radio end. Also the reflected power measured at the radio end allows one to calculate the reflected power at the antenna end based on the cable losses. With both the calculated forward and reflected power at the antenna end of the cable is now “known” it’s now possible to calculate the SWR of the antenna itself. This saves the trouble of having to stick the SWR meter up at the antenna, which in many cases isn’t a realistic possibility. While not likely as accurate as a real reading it’s better than nothing.
  18. Lscott
    You might try something like these. They are rubber boots to protect the finish but also likely less slippy too. Most magnet mounts use a very thin sheet of plastic on the bottom. https://www.arcantenna.com/products/laird-antenex-gro-rubber-boot-for-magnetic-nmo-mount-vehicular-antenna https://strykerradios.com/product/sr-a10mm-magnetic-mount-protective-boot/ Note adding some thickness between the magnet mount base and the mounting surface will decrease the grip force. You may need a larger magnet mount base if you use the boot.
  19. Lscott

    BTECH AMP-U25D

    Lscott replied to WRQG450's topic in Guest Forum

  20. Lscott
    And IRLP, Internet Radio Linking Project. https://irlp.net/
  21. Lscott
    https://dopsys.com/fcc-selects-doppler-systems-to-provide-radio-direction-finders/ https://dopsys.com/direction-finding-products/fixed-site-direction-finders/ https://dopsys.com/direction-finding-products/packaged-direction-finding-systems/#mobile-kit https://www.dopsys.com/doppler-files/appnotes/Using Doppler Systems Radio Direction Finders to GeoLocate Transmitters.pdf
  22. Lscott
    CX-5 Antenna System Analysis.jpg

    From the album: Misc. Radio Gear

    I did a bit of a detailed gain analysis of the antenna system I wanted to install on my CX-5. I ultimately went for the “C” installation. The goal was to see the tradeoffs using different antenna mounts and cable types and lengths. I had to settle for a longer lead in cable length than I had originally wanted but the hit on the gain wasn't too bad. The analysis was done using the older higher gain antenna, CA-2x4MB, which isn't manufactured any more but my old one still works and I have a new one still in the plastic bag. I had purchased two at the time, one to install and the second as a spare. I also have the Diamond SG7500, but its not as broad banded as the old antenna. The Comet CA-2x4SR would have worked provided I had a good ground plane. Since I'm using the luggage rack mount I'm stuck using a no ground plane design type so this antenna is out for the moment. https://forums.mygmrs.com/gallery/image/282-ca-2x4mb-scansjpg/?browse=1 https://diamondantenna.net/sg7500a.html https://diamondantenna.net/c213sma.html https://diamondantenna.net/c110.html
  23. Lscott
    I don’t really see any either because I normally disable JavaScript. I use a script blocker on Firefox and on the iPhone there is an option to turn it off on Safari too. This also does a good job killing annoying ads on other sites too. They also load faster on mobile devices and cuts down on your data usage.
  24. Lscott
    Interesting. I wonder if there are any rules specifically about how ID’s must be done on digital systems. I'm assuming you’re referring to repeaters exclusively, doing the CWID in analog. The question was about subscriber units, user radios, when using a repeater or in simplex mode. In my case, likely not in general, the CWID feature is only available when using NXDN on the Kenwood radios I have. For example the ND-1300, current production radio, when the NXDN version is selected in the programming software the manual CWID TX feature is available. However selecting the DMR version it’s not. I’m trying to find out is there a rule or technical reason why that’s the case. So far I haven’t found anything definitive.
  25. Lscott
    And one wonders why it's getting worse?
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use and Guidelines.

  I accept