wrote:

On Saturday, 6 January 2018 17:35:46 UTC, newshound wrote:
On 06/01/2018 16:09, Brian Gaff wrote:

If they are the ones based on radioactive isotopes I believe you need
to be careful to make sure they get given to the right place. If they
use some other technology then its normally the council electrical
folk who send them for recycling. I remember there was a bit of a
stink when people dumped their old dial trimfones. as the back lit
figures were based on a beta lite ie a radioactive gas in a sealed
tube with a phosphor which the beta particles stimulated and as the
electron changed charge a pulse or photon was emitted giving that
eerie light. Brian


Quite a lot of old Trimphones were dumped in a skip on the Harwell site,
which got them a fine.

https://wikivisually.com/wiki/Trimphone

An audio specialist once claimed that the distinctive "Warble tone" was
perfectly optimised to make it difficult to locate.

it sounded exactly the same as a certain bird. Predictable results.

I think the problem was that certain birds mimicked it. Same effect,
obviously, but it did depend on the morale and IQ of one's local birds.



David Hahn had a use for smoke alarms, but I wouldn't recommend that.
free.uk.diy.nuclear-device may have more info, this group doesn't really
extend to nuclear diy. AFAIK!

The authorities make an exception for home radioactive smoke alarms,
otherwise you need nuclear certification even to move one across the room.


NT


--

Roger Hayter