On Thu, 13 Mar 2008 23:46:46 GMT, wrote:

On 13 Mar,
Frank Erskine wrote:

Automatic light switches with an ORP12, a red spot transistor and a
relay.

And what about before semiconductors? Replace the red spot with a triode.
Neon for the timer.

Well yes - I didn't like to embarrass the youngsters (sub 58s, for
example) on here...
The relay has to be GPO 3000-type, with proper adjustments.

--

Frank Erskine
Be alert - the Country needs lerts.