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Re: RA0SMS vs PA0RDT Active Mini Whip - RA0SMS is Very Noisy - Why?

Posted: Fri Mar 29, 2019 1:21 pm
by illllm
The university on twenty has their miniwhip mounted on a super large metal "pole" :)

Personally, I found grounding the coax shield, reveals more signals. If the coax is pulling signals, then perhaps your antenna is not working efficiently? Does it still pull in stations when there is no power applied?

Re: RA0SMS vs PA0RDT Active Mini Whip - RA0SMS is Very Noisy - Why?

Posted: Fri Mar 29, 2019 1:36 pm
by ultravista
Neither antenna receives any signals without the power applied.

One is a real PA0RDRT (works) and the other is an 'improved' PA0RDT design (does not work).

Since posting the original thread, I bought a cheap Chinese copy of the PA0RDT (eBay) and it works nearly identical to the real PA0RDT. The noise floor is a wee-bit higher but everything tunable with the PA0RDT is also tunable with the Chinese knock-off PA0RDT.

The knock-off is mounted on the same pole, 9v power supply, and uses the same coax, as the RA0SMS. No noise, QRM, or whatever, compared to the RA0SMS. The knock-off is clean.

There must be a design flaw with the RA0SMS.