Tex3,
I never actually got round to building the copper / zinc zinger
due to problems obtaining the zinc rod.
Unfortunately, therefore, I can’t help with any reading from it,
or try the resistors as you suggested. Sorry!.
Maybe tom or one of the others?.
Some thoughts on the saline resistance.
Knowing the circumference / diameter of the tube
and the length in circuit,
it should be possable to work out the volume of
the saline.
Multiplying this by the volume resistance of the saline should
give the resistance.
True resistors are less messy than saline, but I
don’t think that
it would have the same effect …
Oaklawn7inches,
You are correct that saline is a good conductor of electricity.
This is because it is “ionic”. It comprise positive and negative
ions which can be caused to seperate, and thus carry a current.
As for the circuit within the zinger, it would seem to me that with
the single electrode pair (ie one copper and one zinc electrode)
that the effect would be similar two batteries wired in parallel.
If it makes it easier to see what I am talking about imagine the two
copper and zinc electrodes cut in half and connected by the saline.
You then have copper, saline and zinc, with voltage between top and bottom.
In the zinger, two are in parallel, so the only current caused would
be due to the difference in voltage.
In other words, there would be almost the same voltage each “side”
and therefore a minimal current flow.
If a saline filled “two pair” zinger were to be arranged so that the
electrodes were alternated - ie zinc, copper, zinc, copper - then it
would seem that there would be the “double” voltage to drive the current
through the zinger. Thus there would be a rather large internal current.
A sort of self dischaarge. This would most likely lead to a rapid
deteriation of the zinger. I doubt that it would improve the overall
results thought!.
As to the saline in the one pair zinger, it may help by lowering the
source impedance, but I am not certain!.