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California fires: smart speakers and emergency alerts

Subject: California fires: smart speakers and emergency alerts
From: egon at egon.cc (James Downs)
Date: Thu, 26 Jul 2018 11:13:51 -0700
In-reply-to: <[email protected]>
References: <[email protected]> <[email protected]> <CAEE+rGpT2uo3jJi5VT=cOitsYcbZGUPAqXKy854qN9hhozxDbw@mail.gmail.com> <[email protected]> <[email protected]> <[email protected]>

On Thu, Jul 26, 2018 at 12:31:31PM -0500, Chris Boyd wrote:

> Thatâ??s about 1.85 meter wavelength, so a quarter wave antenna would be pretty large.  Iâ??m sure the RF engineers can come up with a way to listen effectively without a huge antenna.

For 162Mhz, a 1/4 wave antenna would have a vertical radiating element of around 17".
However, for receive only purposes, it's not necessary that the antenna be resonant. You can demonstrate this yourself with any FM radio and a paperclip.

Cheers,
-j

References:
- California fires: smart speakers and emergency alerts
  - From: sean at donelan.com (Sean Donelan)
- California fires: smart speakers and emergency alerts
  - From: aaron at heyaaron.com (Aaron C. de Bruyn)
- California fires: smart speakers and emergency alerts
  - From: sethm at rollernet.us (Seth Mattinen)
- California fires: smart speakers and emergency alerts
  - From: valdis.kletnieks at vt.edu (valdis.kletnieks at vt.edu)
- California fires: smart speakers and emergency alerts
  - From: cboyd at gizmopartners.com (Chris Boyd)

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