Submitted 1 week ago by evasync@lemmy.world to amateur_radio@lemmy.radio
hello,
i want to make this antenna (check link) to get sat weather images sata with my sdr.
will it make a dofference if I replace.the plastic parts with wooden?
also is any other type of antenna more suitable for this purpose? (I want it to be as compact as possible because the only space i have available is on my flat’s window)
I know nothing about this, but I am wondering why you want to use wood instead of plastic?
i despise plastic and i want to minimize it where possible.
in this particular case the components will be exposed to the sun and that will degrade the plastic over time, and that is something that wont happen to wood :)
skillissuer@discuss.tchncs.de 5 days ago
wood is fine but make sure to waterproof it if used outside. use as little as practical, performance can change with weather unlike with plastic. no metal fasteners either as this will have weird effects
do you want it to be compact when deployed or compact when stored? you can also make crossed dipole yagi, you probably want it to be rather nondirectional so one director, driven element and reflector would be fine. that antenna is much longer but i think you get the idea www.qsl.net/dk7zb/Cross-Yagi/crossyagi.htm you can also make bifiliar helical antenna but this one again gets a bit directional. you can probably make it shorter than these 5 turns and change pitch too to decrease directionality secwww.jhuapl.edu/…/12-01-Stilwell.pdf you can also make unifilar helical antenna but it needs a big reflector baseplate so it won’t be as compact, it looks like this www.ab9il.net/wlan-projects/wifi3A.html
skillissuer@discuss.tchncs.de 5 days ago
wait, do you want to use it at 140-ish MHz? these antennas will be quite sizable no matter what you do. you can make cross-dipole yagi but with loops instead of straight elements to make it a bit more compact. again, one director will be fine. take reflector + driven element from there www.robkalmeijer.nl/techniek/…/index.html and first director from there iw5edi.com/…/directional-antennas-cubical-quad this will get you antenna looking roughly like a cube with 50cm side. i don’t think you can get much more compact
skillissuer@discuss.tchncs.de 4 days ago
now that i’m thinking, you can make loop antenna with circular polarization and mesh reflector with closer spacing that would be even more compact and that would have more of one sided donut shaped radiation pattern, which would be probably more suitable for your application, but it’s guaranteed to have different impedance and so would require simulation