Follow

so i decided im putting back up my HF antenna, doing it all new! I'm excited.

ยท ยท 1 ยท 1 ยท 2

@freemo Cool!
In August I'm planning to put up a 2m/70cm J pole. I want to try measuring it with a NanoVNA to see whether it has low enough SWR to also be usable at 1.25m. I suspect not, but it seems worth checking.

@brouhaha SWR tells you nothing about its suitability for a particular frequency.. Remember a 50 ohm resistor is 1:1 SWR and a dipole fed with a ladder line is a good performer even at 10:1 SWR

@freemo My transceiver isn't rated for 10:1, though. I'll have to look up the specs. If the measured SWR exceeds to transceiver specs, at least I'll know not to try it.

@brouhaha thats irrelevant. You just stick a tuner on it or add a capacitor/inductor to match at the feed point.

@freemo @brouhaha SWR tells one a lot. Such as "I need some sort of matching here".

@kentborg @brouhaha

Yup, it tells you a lot. Suitability as a transmitter is not usually one them.

@freemo @brouhaha the only thing SWR tells you is how well something is matched to 50ohms. Thereโ€™s no information about radiating efficiency there.

@RFDave @brouhaha

Well its a bit more than that, but yea, SWR doesnt substitutde for radiation effiency

Sign in to participate in the conversation
Qoto Mastodon

QOTO: Question Others to Teach Ourselves
An inclusive, Academic Freedom, instance
All cultures welcome.
Hate speech and harassment strictly forbidden.