Ha!! I just had flash-backs of an aspect of my previous work, on large building
Fire-Systems...
In big buildings, the
Thermal-Detectors are often quite high. When I was testing them, (and
I'm talking about literally 500 to 1000 in big buildings!), I used one of those
Butane 'Portasol'
style gas Irons, with a
Coke can under the screw-in Tip, and the can top cut off. And mounted
it all on the end of an aluminium
extension pole, like for a swimming pool vacuum head.

Used to work perfectly!! (Held up against the detector). Would set them off in about
5 seconds.
Some (stairways/foyers etc) would be up to 5 to 8 metres high! No probs!!

And yes, they can put out a LOT of heat when turned up high, even soldering to a metal chassis!!
