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OffRoaderX

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OffRoaderX last won the day on February 14

OffRoaderX had the most liked content!

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  • Website URL
    https://notarubicon.com

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  • Name
    Randolpho (Randy) Cafe
  • Unit Number
    0
  • Location
    Southern California / Inland Empire
  • Interests
    Making sad-hams cry.

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  1. But if you dont degrade others, how are you going to make yourself feel superior to them and show everyone how much of an expert you think you are?
  2. GMRS is definitely a Bring Your Own Friends service, especially when out in the desert.. We do off-roading/Rock Crawling in JV all the time (will be near there tomorrow).. Keep an eye out for the big orange jeep and say hello - we'll be on channel 16, the official off-road GMRS channel..
  3. Are you sure you have gone through the entire list? And, are you in VFO mode? IIRC you have to be in VFO mode.
  4. OffRoaderX

    CONFUSED

    It's kONPHUKULATION .. Get it right.
  5. I think it is hilarious how "some people" so are completely incapable of grasping the simple fact that just because they dont like something, nobody else on the planet possibly could like it. As @marcspaz noted, many people are more than willing to pay for a simple, easy to use, no frills/no bells&whistles, "americanISH" product. Just because it is not the right choice for you does not mean it's not the right choice for someone else.
  6. Connecting the repeaters to Zello does violate the FCCs rules.. But, nobody really cares, including the FCCs, which has never done anything about the hundreds or thousands of internet-linked GMRS repeaters out there.
  7. I guess this is a great time to announce that I will be putting my NotARubicon "Ranchino" repeater back on Zello (just waiting for one more part to ship) AND, as an added bonus, will also be linking it over the internet to my buddy's repeater located in the Glendale area.
  8. My repeater has a roger-beep and I require that anyone using the repeater also has their roger-beep enabled.
  9. You only need the TX tone. The RX tone is optional, and as you can already see, will cause you confusion - so you should ignore it for now. After you level-up to "expert mode", then you can worry about the RX tone.
  10. I thought this would be a good test for the A.I., so I wanted to see how Grok would answer - you are all now obsolete because it totally out-dorked all of you. Key Points Flat earth: Communication distance is about 3900 km. Real earth: Communication distance drops to about 11 km due to curvature. Flat Earth Scenario In a flat earth with no obstructions, two 5-watt UHF radios can communicate up to approximately 3900 km. This is because, without curvature, the signal can travel in a straight line, limited only by signal strength, not physical barriers. Real Earth Scenario On a real earth, the distance is limited by the line of sight, which is about 11 km for two people each 6 feet tall. This is surprising because it’s much shorter than the flat earth distance, showing how earth’s curvature significantly restricts radio range. Survey Note: Detailed Analysis of UHF Radio Communication Distances This section provides a comprehensive analysis of the communication distances for two 5-watt UHF radios under two scenarios: a flat earth with no obstructions and a real earth considering curvature. The analysis includes all calculations, assumptions, and supporting details to ensure a thorough understanding. Flat Earth Scenario: Theoretical Maximum Distance In a flat earth scenario, with no trees, buildings, or curvature, the communication distance is determined by the signal strength and free-space path loss. The problem specifies two six-foot-tall people with 5-watt UHF radios at the same elevation, with only air between them. Frequency Assumption: UHF radios operate between 300 MHz and 3 GHz. Based on typical usage, a frequency of 430 MHz was chosen, which falls within the common range for amateur radio (400-470 MHz), as confirmed by searches on 5-watt UHF radio frequency range. Transmitted Power: The radios transmit at 5 watts, which is 37 dBm (since 1 W = 30 dBm, and 5 W = 10 log10(5000) ≈ 37 dBm). Receiver Sensitivity: Typical receiver sensitivity for UHF radios is around -120 dBm for 12 dB SINAD, based on searches for UHF radio receiver sensitivity. This means the receiver can detect signals as weak as -120 dBm. Path Loss Calculation: The free-space path loss in dB is given by the formula: Path Loss (dB)=32.44+20log⁡10(d)+20log⁡10(f) where (d) is the distance in kilometers, and (f) is the frequency in MHz. For f=430 MHz, 20log⁡10(430)≈52.6772 dB. The total path loss is: 32.44+52.6772+20log⁡10(d)=85.1172+20log⁡10(d) For the signal to be detectable, the received power Pr=Pt−Path Loss≥−120 dBm. So: 37−(85.1172+20log⁡10(d))≥−120 Simplifying: 37−85.1172−20log⁡10(d)≥−120 −48.1172−20log⁡10(d)≥−120 −20log⁡10(d)≥−120+48.1172 −20log⁡10(d)≥−71.8828 Dividing by -20 (and reversing the inequality): log⁡10(d)≤3.59414 d≤103.59414≈3890.2 km Rounding to a reasonable figure, the communication distance is approximately 3900 km. This distance is theoretical and assumes no atmospheric losses beyond free-space path loss, which is reasonable given the problem’s conditions of “no trees or buildings or anything between them but air.” Real Earth Scenario: Impact of Curvature On a real earth, the communication distance is limited by the line of sight due to the earth’s curvature. The problem specifies no obstructions other than air, so we focus on the radio horizon. Height of Antennas: Each person is six feet tall, approximately 1.83 meters, which is 0.00183 km for consistency with the earth’s radius in kilometers. Earth’s Radius: The earth’s radius is approximately 6371 km. To account for atmospheric refraction, especially for UHF frequencies, the 4/3 earth radius model is used, making the effective radius r′=4/3×6371≈8494.67 km. Radio Horizon Calculation: The radio horizon distance for one person is given by: d=2×r′×h Substituting r′=8494.67 km and h=0.00183 km: 2×8494.67×0.00183≈31.048 d=31.048≈5.57 km For two people, the total line-of-sight distance is the sum of their individual horizons, assuming they are at the same elevation: dtotal=2×5.57≈11.14 km Geometric Horizon for Comparison: Without refraction, using the geometric horizon ( r=6371 km): d=2×6371×0.00183≈23.34426≈4.83 km dtotal=2×4.83≈9.66 km The 4/3 model extends the range, which is standard for VHF and UHF frequencies, as confirmed by radio horizon for UHF frequencies. Signal Strength Check: At 11.14 km, the path loss is calculated as: 32.44+20log⁡10(11.14)+20log⁡10(430) 20log⁡10(11.14)≈20×1.047≈20.94 , and 20log⁡10(430)≈52.6772 , so: Path Loss≈32.44+20.94+52.6772≈106.0572 dB Received power Pr=37−106.0572≈−69.0572 dBm , which is well above -120 dBm, so signal strength is not the limiting factor; the line of sight is. Given UHF frequencies’ line-of-sight nature, the communication distance is limited to approximately 11 km, aligning with the 4/3 earth radius model, which accounts for slight atmospheric refraction. Table: Summary of Calculations Scenario Frequency (MHz) Receiver Sensitivity (dBm) Limiting Factor Distance (km) Flat Earth 430 -120 Signal Strength ~3900 Real Earth 430 -120 Line of Sight (4/3) ~11 Additional Considerations Frequency Choice: The choice of 430 MHz is based on common UHF amateur radio frequencies, supported by 5-watt UHF radio details. Receiver Sensitivity: Confirmed through searches that -120 dBm is typical for UHF radios, ensuring the calculation’s validity UHF radio sensitivity. Curvature Impact: The significant drop from 3900 km to 11 km highlights how earth’s curvature restricts UHF radio range, which is surprising for laymen expecting longer ranges. This analysis ensures all details from the problem are addressed, providing a complete and self-contained response.
  11. It seems like in the morning his medications have not yet kicked-in because by evening his posts are usually not as rhee-tard-ted. One would also think that he would figure out that nobody likes him and he would go away, based on the constant corrections people post pointing out how virtually nothing he says is correct or helpful. On the bright-side, he is a great example of someone with zero self-awareness, and even less social-grace or abilities.
  12. Because that is apparently what "some people" do best - its like a hobby.
  13. Per my sources at Midland there were "issues" with the company making the unit, and no longer sell it - but you can still buy one directly from the company as mentioned by @WRUU653 .. I have one and am still very happy with it after several years - although i yanked out the Midland that was in it and shoehorned in KG-1000G+ .
  14. "can".. but, based on their enforcement history over the last 15 years, they won't.
  15. As long as you are in the Themes settings, you should choose the "NotARubi" theme for optimal performance.
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