• 3 Posts
  • 28 Comments
Joined 2 years ago
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Cake day: June 21st, 2023

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  • AG7LRtoAmateur RadioNew radio day
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    5 days ago

    You can have separate banks for each city. That way you can scan just the repeaters for the city you are in. I have a radio with 1000 channels and no memory banks. I have to hook it up to the computer and reprogram it whenever I go to a different area.

    On the Yaesu radios that support memory banks, you don’t have to use them. You can put the same channel in multiple banks or put every channel in one bank.


  • AG7LRtoAmateur RadioNew radio day
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    14 days ago

    That’s a nice radio. It has memory banks, which are essential for managing the 1000 channels it holds. For some reason, Yaesu stopped putting memory banks in their newer radios. The US version is tri band, which is nice if you have any 1.25m repeaters nearby. The batteries are a bit expensive though.






  • Yes, you can use a vertical antenna, but it’s not ideal. There is a null overhead. They will work better on lower elevation passes. If the vertical is on an HT, you can hold it sideways to receive on a high elevation pass.

    There are omnidirectional antennas for satellites such as a quadrifilar helix or turnstile antenna that will work very well for stronger signals like the ISS and the old NOAA satellites.



  • AG7LRtoAmateur Radio"Strong transmitters" near RTL-SDR.
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    7 months ago

    Keep the transmitting and receiving antennas a few wavelengths apart to prevent damage, farther if you’re using an amplifier. You can transmit right next to the RTL-SDR with an HT if you disconnect the antenna from the SDR. It will still receive the signal from across the room.








  • The FCC sets what parts of the bands can be used for phone and what’s CW or data only. Apart from that everything is basically a gentleman’s agreement. Since HF can go a long ways, there’s no point making local band plans for it. VHF and up is shorter range and some areas have different needs than others. There are frequency coordinators that handle the band plans and repeater pair assignments. Some states have more than one frequency coordinator for different parts of the state. Some frequency coordinators only handle repeater pairs and don’t publish a band plan.





  • Sdrplay does work on Linux. Unfortunately, the driver is closed source though. You will have to install it manually and possibly have to compile the software you use to enable that driver. Also, the driver is only available for X86_64 and ARM64, so if you are using any other CPU, then it won’t work.

    I have an SDRplay RSP1A and it works best using SDR++. GQRX works, but there is no low IF mode and no control over the filters or bias-t. CubicSDR and SDRangel work too, but low IF mode is buggy. The hardware is good, but I never would have bought it had I known the driver was closed source.



  • You can run a dipole between two houses, just be sure to do your RF exposure calculations and don’t be surprised if you pick up a lot of RFI. You will need to use insulators between the antenna wire and the supporting rope. There is a lot of voltage on the ends of the dipole. If the dipole is less than 1/4 wavelength off the ground, most of the signal will go up. That’s good for NVIS on the lower bands, but bad for DX.

    You can put multiple dipoles on the same cable, it’s called a fan dipole. The wires have to be spread out and can be a pain to work with, but you can get an antenna that’s resonant on multiple bands.


  • AG7LRtoAmateur RadioRedneck engineering manpack
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    2 years ago

    Most radios won’t run on 20V or higher. At 15V or lower, USB PD is limited to 3A.

    If you wanted to get 100 watts, you would need a buck converter to step 20V down to 13.8V. Now you have two switch mode power supplies producing RFI.