I would not say that. Aside from measuring a monopole + cable and not just a monopole, it is not only loaded but also 27 cm long (17 cm for 433 MHz). Probably in order to present a good match to the receiver.
I have found the UHF, similar but shorter antenna; this one is 433 MHz and capturing all sort of signals.
Included:
? NESDR SMArt SDR in black brushed aluminum enclosure
? Antenna base w/ 2m RG58 cable
? Telescopic antenna mast (variable frequency)
? 433MHz (ISM) antenna mast (fixed frequency)
? UHF antenna mast (fixed frequency)
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On Friday, March 7, 2025 at 12:54:54 AM GMT+2, Jim Lux via groups.io <jimlux@...> wrote:
Sounds quite low.? A monopole against a ground plane will be in the 25-35 ohm range.? That one is obviously center loaded, but perhaps not for 433 MHz (more likely cell band at 850).? Did you also get the extendable whip antenna? put that on the base and make it about 17 cm long.? Or a piece of wire.
-----Original Message-----
From: <nanovna-users@groups.io>
Sent: Mar 6, 2025 2:34 PM
To: nanovna-users@groups.io <nanovna-users@groups.io>
Subject: Re: [nanovna-users] Measuring Impedance for the 433 MHz RTL-SDR Antenna
Whoops!
(first picture, antenna is on the left)
On Friday, March 7, 2025 at 12:31:47 AM GMT+2, W0LEV via groups.io wrote:
No images attached.
Dave - WØLEV
On Thu, Mar 6, 2025 at 8:22?PM kellogs via groups.io wrote:
? Hi,
i am trying to get a grip on using the nanoVNA. Does anybody have the 433
MHz antenna + base from the RTL-SDR kit ?
Firstly calibrated at device port (no cable), then measured the loaded
monopole through its magnetic antenna base at 433 MHz (first picture,
antenna is on the left):? Nooelec - Nooelec NESDR SMArt v5 Bundle -
HF/VHF/UHF (100kHz-1.75GHz) RTL-SDR Kit with 3 Antennas. RTL2832U &
R820T2-Based Software Defined Radio
Mounted on car hood:? 8 ohm at resonanceMounted on bicycle:? 7.5 ohm at
resonance
Does it sound right ?
--
*Dave - WØLEV*
--
Dave - WØLEV
