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End-user Alert Delivery (was Re: NDAA passed: Internet and Online Streaming Services Emergency Alert Study)


From: "Jay R. Ashworth" <jra () baylink com>
Date: Thu, 14 Jan 2021 03:56:48 +0000 (UTC)

----- Original Message -----
From: bzs () theworld com

On January 4, 2021 at 21:19 valdis.kletnieks () vt edu (Valdis Klētnieks) wrote:
First, that means your smoke alarm batteries run down faster, which is
a major issue.

That's the sort of argument I label "all sign, no magnitude".

How much faster? If it took one minute of battery life off a 10 year
battery would that be a problem? 30 minutes?

Well, let's address that.

Last time I looked, consumer residential smoke detectors were still running
off 9V alkaline batteries, which are expected to run the device for 6 months
of 1/99 duty cycle (or less, probably *way* less).

An Energizer 9v is rated for 8.4VDC in the very general vicinity of 500mAh.

How does that compare to other factors like ambient temperature which
also affects battery life but we mostly consider "in the noise"?

A lot.  Increasing the alert count from the 1 or 2 it probably is on most
smoke alarms to 2 or 3 a *week*, with LOUD analog speaker alert playback is
going to change that duty cycle, probably, to something like 10/90.
[ All numbers pulled out of my butt for illustration, but probably within
half an order of magnitude. ]

Could we make the battery just a little more powerful? How much power
would a bit of circuitry waiting for a "turn on! there's a new message
coming in!" need?

Well, parsing for EAS on the receiver is going to make its drain non-trivial,
too, I think.

But there are "increasing the battery replacement frequency" problems *and*
"increasing the battery capacity and hence price, not to mention general 
availability" problems balancing that out.

Any way you play it, it has to be an optional model, not a general takeover 
of the field, I suspect, or the "well we just won't bother anymore" factor
takes over.

Cheers,
-- jra
-- 
Jay R. Ashworth                  Baylink                       jra () baylink com
Designer                     The Things I Think                       RFC 2100
Ashworth & Associates       http://www.bcp38.info          2000 Land Rover DII
St Petersburg FL USA      BCP38: Ask For It By Name!           +1 727 647 1274


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