Michigan QRP Club Zoom meeting
Posted: Wed Oct 23, 2024 7:27 pm
Please join us Thursday (and every Thursday) at 4PM Eastern for the Michigan QRP Club weekly QRP Chat where the main topics will be QRP and other ham interests. It's fun, it's easy, and it's free. You only need a computer, a smart phone, or a tablet that can connect to the Internet. OR if you can't be close to any of those you can join by audio with any standard phone. Just follow the directions below. No software needs be loaded or installed. Anyone can join and non members are welcome. Details are here:
https://www.miqrp.net/zoom
Thursdays topic will be Lighting Protection
We had 13 folks join us for the chat on 17 October. The topic was balun / unun design and modeling.
John M7FZC
Ed AB8DF
Pete WK8S
Ernie W3ETE
Dave N8SBE
Marv W5DT
Yvon AE7YD
Casey KC9IH
Neil N9NL
Dan KB6NU
Stan WB8QJZ
Stan KC7XE
Jacob N3JU
We discussed the three reasons one might want to use a balun / unun, common mode currents, balance to unbalance transitions and Impedance matching. We looked at the classic paper by Roy Lewallen, W7EL, “Baluns: What They Do And How They Do It”.
https://www.arrl.org/files/file/History ... len(1).pdf
It describes the the reasons for using a balun / unun and provides results of several experiments he conducted to explore the validity of the theories.
We also looked at “A Ham's Guide to RFI, Ferrites, Baluns, and Audio Interfacing” by Jim Brown K9YC.
http://audiosystemsgroup.com/RFI-Ham.pdf. It focuses on RFI and reducing / eliminating RFI interference from commercial devices.
Another item we looked at was an on line calculator by VK3CPU
https://miguelvaca.github.io/vk3cpu/toroid.html
It predicts the RF characteristics of a ferrite or powdered-iron toroid wound as an inductor or suppressor.
Stan KC7XE did an excellent job showing his common mode choke and his setup with an end feed antenna. He also showed how he tested with a Nano NVA.
Jacob is new to the chat. He does digital FT8 etc. Wants to do CW. Uses a IC7300, QCX+ on 40 meters and a QMX in the box.
Next week topic will be Lighting Protection. Anyone can take the floor and tell us about their knowledge of Lighting Protection. We will go one by one until all have had a chance to have the floor. Files, pictures and presentations can be shared if you have any. There will be time for comments and questions. Please try to stay muted when someone has the floor.
https://www.miqrp.net/zoom
Thursdays topic will be Lighting Protection
We had 13 folks join us for the chat on 17 October. The topic was balun / unun design and modeling.
John M7FZC
Ed AB8DF
Pete WK8S
Ernie W3ETE
Dave N8SBE
Marv W5DT
Yvon AE7YD
Casey KC9IH
Neil N9NL
Dan KB6NU
Stan WB8QJZ
Stan KC7XE
Jacob N3JU
We discussed the three reasons one might want to use a balun / unun, common mode currents, balance to unbalance transitions and Impedance matching. We looked at the classic paper by Roy Lewallen, W7EL, “Baluns: What They Do And How They Do It”.
https://www.arrl.org/files/file/History ... len(1).pdf
It describes the the reasons for using a balun / unun and provides results of several experiments he conducted to explore the validity of the theories.
We also looked at “A Ham's Guide to RFI, Ferrites, Baluns, and Audio Interfacing” by Jim Brown K9YC.
http://audiosystemsgroup.com/RFI-Ham.pdf. It focuses on RFI and reducing / eliminating RFI interference from commercial devices.
Another item we looked at was an on line calculator by VK3CPU
https://miguelvaca.github.io/vk3cpu/toroid.html
It predicts the RF characteristics of a ferrite or powdered-iron toroid wound as an inductor or suppressor.
Stan KC7XE did an excellent job showing his common mode choke and his setup with an end feed antenna. He also showed how he tested with a Nano NVA.
Jacob is new to the chat. He does digital FT8 etc. Wants to do CW. Uses a IC7300, QCX+ on 40 meters and a QMX in the box.
Next week topic will be Lighting Protection. Anyone can take the floor and tell us about their knowledge of Lighting Protection. We will go one by one until all have had a chance to have the floor. Files, pictures and presentations can be shared if you have any. There will be time for comments and questions. Please try to stay muted when someone has the floor.