Leon said:
I've seen it mentioned on the QRP-L amateur radio forum; it's a waste
of money for electronic work, at any rate.
Agreed. I have one and have given them as gifts, but you have to
realize that they are best at precisely what the commercial says they
are. I haven't even attempted any kind of real electronics work with
mine, because I know it'll be a disaster. Instead, it's used for bulk
(but not too bulky) soldering jobs, e.g. wires to connectors, patch
jobs, etc.
If you try to heat too much material with it, you won't get anywhere,
but for medium-sized jobs it does indeed work very well, as advertised.
I think it passes a high current through the joint to be soldered.
Dirty little secret: the only electronics (at least in the basic $20
version) are the LEDs. Literally, all the "magic" is in the tip, made
of some material that presumably aids in the process somehow. The
switch connects the two ends of the 4 AA's to the two sides of the tip,
and incidentally the LEDs. A current dump across the part to be
soldered (6V at whatever current the AA's can put out) heats it up
enough to melt solder and get the job done. I'm tempted to take some
batteries and plain old wire and see what happens, should be similar
results except for the sacrificial aspect of the tip.
I don't think it's actually going to be any kind of problem for mildly
sensitive electronics, unless you're not very careful. Touching one
side of the tip to the circuit won't do anything, because the circuit is
open on the other end, batteries or no. As the other side connects, the
voltage is shunted entirely through the pin/wire/etc being heated. The
only way you're going to get a high-current 6V dump through your part is
if you manage to touch each half of the tip to separate ends of the
circuit and allow a loop through your parts.