On Thu, 24 Nov 2022 17:19:39 +0000, Andy Burnelli <
sp...@nospam.com>
wrote:
>Happy Thanksgiving!
Bah Humbug.
>What [automated] apps (or techniques) do you use to ensure radios are off?
> (This is not a question of manual techniques.)
You're asking the wrong question. What you really need, before you
can turn off various communications devices in your smartphone, is a
means of verifying that they're actually turned off. Using apps and
settings on the phone are not sufficient because they often lie. For
example, turning on airplane mode probably does disable all the major
transmitters in the phone. The transmitters can easily be turned back
on in the settings app, but the phone will still indicate that it's in
airplane mode.
What you need is something like a spectrum analyzer that will show
everything from 13.56MHz (NFC) to the highest frequency in the 5G
cellular band, 39GHz.
13MHz to 1.7GHz can easily be done with a minimal RTL-SDR receiver.
<
https://www.google.com/search?q=rtl-sdr+dongle&tbm=isch>
There are ready to use spectrum analyzers suitable for detecting if
your phone is transmitting. For example:
<
https://www.aliexpress.us/item/2251832799164953.html>
Don't worry about lousy sensitivity. The spectrum analyzer will be
very close to your smartphone and should indicate if there's any RF
being belched by the phone.
<
https://www.google.com/search?q=sdr+spectrum+analyzer&tbm=isch>
<
https://www.rtl-sdr.com/tag/spectrum-analyzer-2/>
Unfortunately, there are some 4G frequencies between 1.7 and 2.2GHz
that the commodity spectrum analyzer can't see. Also, the various
microwave 5G frequencies are not covered. It's possible to build a
better SDR (software defined radio) spectrum analyzer that does it
all, but it will probably cost more than you want to spend.
Anyway, once you have a way to confirm that your phone is not belching
secret messages to the dark lords running the evil empire, you can ask
about and test automated apps that will insure your phone's silence.
--
Jeff Liebermann
je...@cruzio.com
PO Box 272
http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS
831-336-2558