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Showing content with the highest reputation on 09/24/22 in all areas

  1. axorlov

    Coax and coax calculators

    You don't even need a calculator for these two. Your second link shows loss at 450MHz (2.7dB), and little googling brings this page: https://abrind.com/coax-guide-2/?gclid=EAIaIQobChMIhor86fWt-gIVpT2tBh1P-gcyEAAYASAAEgLy4_D_BwE where loss for 25400 at 450MHz is 3.3dB. So, Wireman is better, but LLC-25400F is a direct burial.
    3 points
  2. The best antenna for you is going to vary a bit, depending on where you are going to be using the radio and what you want to accomplish. On a vehicle, a 5/8 wave antenna is going to show at least 3dB gain over a 1/4 wave, and at least 1dB of actual gain (depending on design, it can be much higher). This antenna has the least amount of elevation tolerance. So, if you live in a hilly/mountainous area, this may not be the best option, but it would be good in large geographically flat areas. A 1/2 wave doesn't require a ground plane and has about 2.1 dB of gain over a 1/4 wave, but it has no actual gain... its straight break-even. It also has a bit more tolerance to elevation. A 1/4 wave actually has a loss of about 2/10ths of a dB. While it doesn't provide as much range, in hilly or mountainous areas, its going to be the best choice due to the very high elevation tolerance. Based on this, I actually carry a 5/8 wave antenna that is about 32" tall and about 6dB gain, and a 1/4 wave antenna. Then I just swap them on and off the vehicle depending on the terrain I am in and the range needed.
    2 points
  3. WRKC935

    Grounding information

    Ahhh, he just don't like me much. So he gets in his digs anywhere he can. I pretty much ignore his shenanigans at this point, as they really don't effect me and if it gives him pleasure to badger me, at least he's not doing it to someone else that might take it to heart. A lot of it was changes in the routing of grounding. They added / changed the routing of grounding to the floor in new builds from it going up. The other thing that was added was site safety and air born concerns with working in a tower site, mostly bird dropping concerns. They went woke and renamed the Master Ground bar to some other WOKE thing that doesn't include the name MASTER. Not that the subordinate bars were called SLAVE but whatever. I actually commented in training that the next change would be the removal of male and female designations for RF connectors. And that we would quite possibly all be switching to the HP hermaphrodite connectors for all cabling and connections. Yes, that's really a thing, at about 200 bucks a piece. I believe they were the APC-7 connector. But they were truly sexless and would attach to each other without a male and female specific connector. Turned out the trainer was on the R-56 steering committee and wasn't real impressed with my comments about it being the R-56 WOKE revision. I believe he was somehow offended, and made comment about folks and their right to identify any way they want to. I replied by agreeing 100% and informed him that I identify as an offensive asshole, so I was 100% covered if he was offended. Which is my normal reply to all discussions of that topic. Outside the WOKE additions and changes in definitions, there were some additional situations with grounding antenna's on building roofs that were covered. And the other thing I remember was cable management with CAT-5/6 cabling now that Gigabit Ethernet was a thing. The old standard was written prior to much of that. I believe they added the bonding for armored Ethernet and Fiber cables as well. Again stuff we didn't have when the last standard was created. But I will say the bonding and grounding section is worth reading. And will at least sort of hold your interest. As far as the rest of it, if you are having issues getting to sleep the standards for the height of lighting above the cable tray, and the height above the racks for cable tray. The requirements for fire suppression equipment and it's locations and other really boring stuff, reading that will put you right to sleep. Conducting an audit of a site at this point is very difficult. You almost need to make a detailed video of all aspects of the site and then review it with the standard open and compare what you are seeing wit what the standard says. There is A LOT to know and you can easily miss things with only one pass through a site. Like any other code, the purpose of it is personal safety first and foremost. Followed by the reliability of the equipment in the site and the system as a whole. And while some of it applies to the average guy's install in his basement, a BUNCH of it either doesn't apply, or would be too costly to the average radio operator to implement. But, here's the thing with this standard. And why it's important. In a dispatch site with a co-located RF site, meaning a site with dispatchers and a tower. There is an electrical path that exists from the top of the tower to the dispatchers headset if they are using a wired headset and at minimum the path exists to the computers and radios in the room where the dispatchers are. They can't STOP doing their job when a lightning storm rolls past. So their protection is of the utmost importance. And when a government entity want's to save on the grounding and bonding work needed for a site like this, making that statement typically shuts the discussion of cutting corners down about the labor and material cost for it.
    1 point
  4. Ok, thanks. I was thinking they were around that, per 100' but wasn't sure I was looking at the right info. The LLC-25400F will be MUCH easier to work with. That Wireman stuff is almost as bad as hardline
    1 point
  5. WRKC935

    Grounding information

    2017 manual. That's the current standard and the one I just certified on last year. Scanning it??? It's 736 pages.... NO I ain't gonna scan it. 68P81089E50-C_Standards_and_Guidelines_for_Communication_Sites_R56.pdf
    1 point
  6. A picture is worth a thousand words, right? Look at page 3 in this document. They show the simplest solution for your situation: https://reeve.com/Documents/Articles Papers/Reeve_AntennaSystemGroundingRequirements.pdf It simply depicts a lightning arrester inserted into the feed line right where it enters the house and then connects the lightning arrester to your grounding bus. It’s a direct connection from the shield to building ground and a gas discharge tube to connect the inner conductor to ground to protect against static.
    1 point
  7. I my location there is a general "Net" meeting once a month on the GMRS repeater. It's run similar to what you hear on Ham repeaters simply because the format works. Lately there is a "Prepper's Net" on Tuesday nights each week. I think the current roster has about 177 registered users for the repeater. The repeater is owned by the City of Troy and was their backup machine for the fire department in the beginning.
    1 point
  8. Sometimes people do. Really depends on your local repeaters/linked repeaters.
    1 point
  9. According to the FCC, if you are using a GMRS radio, thou must use your callsign on all channels, regardless of the power-output you have set. The question is, will they care if you dont.. and according to the FCC's enforcement database, they don't.
    1 point
  10. Lscott

    Sporadic DMR activity.

    I pretty much agree with your points. Sooner or later digital voice will happen. I would much rather have the FCC get ahead of the game and institute some regulations to keep order rather than let things go and end up with the wild west of various modes trashing each other.
    1 point
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