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Showing content with the highest reputation on 06/06/21 in all areas

  1. Unless its different from the ham bands, licensed business users are the primary users and other licensees are secondary and must yield. UPS is licensed on a chunk of 1.25m in the ham spectrum, but it turns out they decided not to actually use it. If, when and where UPS decides to use it, hams are secondary and have to let UPS do as they wish on the business licensed part of the band. You can look it up, but I have found it a bit tedious
    1 point
  2. I believe that university was grandfathered on that frequency. They have been using it since the 80s (that I know of) when it was a licensed frequency. I read that previously licensed businesses can keep the license as long as then dont make any changes.
    1 point
  3. Just remember that higher cable loss results in BETTER SWR.... (but not better radio performance). I do not necessarily think this is what's going on in this particular situation though.... unless something is really wrong with the cable itself or a connector is defective. Minimum return loss is twice the cable loss. So if your cable loss was 3dB your min return loss would be 6dB which means the worst SWR you could ever see is 3:1 even with no antenna at all. (Of course, no mobile install would have such a high coax loss with only 20' of cable.) You can see this if you just install a 3dB attenuator on the SWR meter with nothing at all attached after it. Ham guys are often puzzled when they upgrade (a 75' run or whatever) to low loss coax then end up with a worse SWR. The antenna was always a poor match but it was masked by the lossy coax. Of course their radio will actually radiate more power than before with the better coax even with the worse looking SWR. More power reaches the antenna and therefore more power is reflected back.... with the same antenna as before. Length of coax does not affect SWR at all except for the difference in loss associated with it. It can however affect forward radiated power if your radio output is not a true 50 ohms... and most are not. They are designed to "work into 50 ohms." This does not mean that they "look like 50 ohms" when looking back into the output port. There may be impedances other than 50 ohms which result in better (or worse) power output. I've seen this on my KG805G with a ham radio 70cm antenna and a certain length of coax. The radio will actually put out more than the typical 4-5W with some lengths of coax. Of course the "wrong" impedance can also cause instability or excess dissipation so you want to operate your radio into something reasonably close to 50 ohms. Any SWR better than 3:1 should be safe though. Many low power hand held or mobile radios would be "safe" into just about any impedance. Vince
    1 point
  4. You're hearing FRS, very likely. And FRS can be used for business or anything. It's legal.
    1 point
  5. Thanks for suggestion. But the problem is that other good insert is not good and screw is too long. So, I ordered two kits from Amazon and will replace both inserts like Landshark did. Metric Female Thread Knurled Brass Threaded Insert Embedded Nuts Assortment Kit https://www.amazon.com/gp/product/B07GLJ7KCJ Laptop Notebook Computer Replacement Screws Kit https://www.amazon.com/gp/product/B07HC3LQYS
    1 point
  6. By ‘monitor option’ are you referring to the ability to manually open squelch and monitor the frequency regardless of tone settings? If so, the radio does have that. The small button on the mic, located below the PTT button, does just that. Regarding SWR, SWR values change based on the frequency used for the test. Based on the tuning of the specific antenna, the best SWR reading may be obtained higher or lower in its operational range. A key point however is that SWR has zero to do with the radio being used and everything to do with the antenna system (coax/feed-line and antenna). So if you are using an inline SWR meter (the typical type) between radio and your antenna system, the SWR should not change whether you are using a $50 radio or $1000 radio so long as both of them are outputing the same frequency for the test. In repeater mode your radio is transmitting on 467.xxxx frequencies. In simplex mode your radio is transmitting on 462.xxxx frequencies. If you have better SWR on the simplex channels then your antenna is better tuned to those frequencies. Michael WRHS965 KE8PLM
    1 point
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