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LeoG

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LeoG last won the day on December 25 2024

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  1. Ok I came back to this radiation pattern and I think I'm understanding it a bit more. Basically you need to think of it as angle and not distance. So if you put the antenna at 20' and another antenna a mile away still at 20' then the gain is 9.77+/-. If you have that antenna on a mountain top at 400' and the same receive antenna at 20' the angle is going to be much greater and you follow that angle on the graph and where it connects with the blue line is the gain that you will have. Power received will be determined by the square of the distance. So from my shop to my house the angle is 0.52º so that keeps the gain pretty close to max. Probably drops it by .5db or something like that. Hard to even see it with the fat lines and the resolution of the graph.
  2. Have you tried other channels besides those two? Odd it's displaying it two different ways.
  3. It should have a dual watch. Mine works fine. Are you sure you don't have an RX tone on the receiver? Make sure the RX CTCSS and RX DCS are both set to off.
  4. Yup. multipath reflections can really affect reception/transmission if you get your antenna in just the wrong position. In the house receiving a weak station moving the HT just a few inches can make or break the reception. Same exact thing for an outdoor antenna I would assume. All summer long I was receiving a repeater and the signal was great. I figured as winter approached and the leaves fell off it would only get better. Was really wrong about that. The signal degraded by a huge factor to the point where sometimes it was getting under the squelch and I had to lower it. Now that we are in full winter, all leaves that are going to fall have. The signal is better but nothing like it is in the summer. I assume it's just multipath interference and antenna position.
  5. I know this is more about placing an antenna on a vehicle and having directional qualities because of where you place it but I have a weird dilemma with a base antenna I've had the same antenna on my small repeater at my shop and it has given me mediocre results ever since I put it up there. After we had some wind my cheap mount folded and the antenna leaned. I straightened it up and reinforced it best I could and life went on. Then another agressive wind came around for a solid week and the mount failed again. The antenna was at about a 15º lean and the repeater was contacting my house very well. Thought it was odd. So after the winds died down after a week I got a much sturdier replacement for my mount and got the antenna up vertical again. It's about 2' lower because I separated the mounting brackets more to take the leverage the wind produces on the mast. I could get to my house base station, the wife said I was coming in great. She on the other hand was barely making the repeater. And when she was it was horrible. So last night I started testing with a voice activated recorder. Driving away from the repeater toward the house calling out at different streets til I reached my driveway, tested there with an HT and then in the house testing the base station. I did this 4 times with not great results. Found that the HT I use normally in the shop wasn't doing a great job and swapped it out. Tested in the shop and then in the office. I went up on my ladder and loosened up the mount and turned the antenna about 10º and now it started to come in better. I still don't know as of yet if it'll work as good as the test I did last night. But that test was very good. It always comes in better later at night than in the normal work hour time. So I'm just wondering why my omnidirectional antenna seems to be far from omnidirectional. Seems like there is a distinct lobe that has a 20dB or more lack of power. The repeater is about 42 watts and the house base is 25 watts, both measured out the backside of the radio. House is 84' LMR400 and the shop is 50' LMR400. It's line of sight but heavily treed. More testing will be done today, this time not all by myself.
  6. I would agree with this. I have mine set up for 4 seconds with a courtesy beep at one second after the last person has unkeyed.
  7. Rather the hoards go to CB and leave the GMRS frequencies open.
  8. Didn't think about that. I'm always in a full metal surround truck.
  9. Well then use a CB walkie talkie inside the cab. Almost any external antenna will beat the tar out of an antenna inside a vehicle.
  10. Doesn't seem like a comparison that fair. Using a 2 watt UHF with an integrated antenna inside a vehicle against a 4 watt CB with an external antenna. Hardly apples to apples. More like apples to fish sticks. Most UHF HTs claim 5 watts but put out more like 4. So if you put a GMRS on a small external antenna it would be much more of a fair comparison.
  11. Are you saying 462MHz will penetrate woods better than 27MHz. Because GMRS does pretty poor in wooded areas by my experience, especially in leafy woods
  12. I sort of agree. Especially from baby monitors.
  13. I see he left his calling card
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