Author Topic: Question or observation.  (Read 3783 times)

AUROVAL

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Question or observation.
« on: December 31, 2023, 07:53:58 pm »
I have a question or observation.

When using the Pira P275 analyzer only powered by the mains, without connecting to the computer, the reception level is optimal at 5 segments (IMG_01)

When used when connected to power and to the computer via RS 232, the reception level drops considerably (IMG_02).

When using it via USB, the reception level also drops considerably (IMG_03).

Regards.

Jan

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Re: Question or observation.
« Reply #1 on: December 31, 2023, 08:12:21 pm »
With correct antenna this never occurs. It occurs if you're using only the telescopic antenna because such antenna is only a half of the dipole. The second half is the metal case and any cable connected to it, effectively collecting all the PC noise. See the device manual for resolution.

AUROVAL

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Re: Question or observation.
« Reply #2 on: December 31, 2023, 08:15:00 pm »
With correct antenna this never occurs. It occurs if you're using only the telescopic antenna because such antenna is only a half of the dipole. The second half is the metal case and any cable connected to it, effectively collecting all the PC noise. See the device manual for resolution.

Hello Jan
What would be the best antenna?

Thank

Jan

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Re: Question or observation.
« Reply #3 on: December 31, 2023, 08:33:35 pm »
  • The antenna should be connected by a few meters of coaxial cable so you can position it independently
  • Balun is necessary between the antenna and the cable, to prevent unwanted reception by the cable itself
  • A half-wave dipole has usually optimal performance and requirements for space

Operation is still possible with simple aerial, but in some situations the reception may be insufficient. The manual brings some more details.