so I bought a $50.00, AC/DC, 5 inch,
B&W TV from RadioShack and
brought the AGC voltage to a jack in
the rear. It goes up the ladder just fine
and runs on batteries if you don't
want to sling a 50 foot extension cord
up on the roof. My DVM shows me
when I'm aimed right, and the picture
helps me see if I have ghosts. It's
better than any expensive field
strength meter, and the frequency is
continuously, manually, tunable.
C. L. Larson
#2 In order to build a suitable UHF
field strength meter, you'd be looking
at a sizeable outlay to get the
sensitivity required. An easier way is
to borrow a pair of FRS radios, station
one with a viewer at the TV set while
you orient the antenna on the desired
channel. Moving the antenna back
and forth until an average mid point
results in best reception. The FRS
radios serve as communication
between you and the TV observer.
This method is suitable for any
frequency range of interest.
Ottawa, Ontario, Canada
[6044 - June 2004]
If I were to take two 500,000
volt stun guns and connect both
positive outputs together and both
negative outputs together, would I
have 1,000,000 volts? I’m planning
an experiment which uses high
#1 NO. In the first place, the output
should be connected in series, plus to
minus. But the outputs are not DC
and not the same frequency, so they
don't necessarily add. However, I
would expect the voltage to be more
than one alone.
#2 Such a simple question — but
one for which a technically accurate
answer is horrendously complicated.
As for the proposed experimentation
— DON'T TRY IT!!!
The insulation on those devices —
while good enough for the voltage
they produce — is NOT adequate to
contain double that voltage, nor
anything even close to double it. Not
to mention the difficulty you will have
in finding something with adequate
insulation, to use to tie them together.
If you try this experiment, it is
virtually guaranteed that you'll have
some form of catastrophic failure,
with destruction of the gear, and
serious hazard to life and limb.
The semi-safe way to experiment
with 'very high' voltages is with static
electricity. Search the Internet for
'Wimhurst static machine' or 'Van de
Graaf generator' for some starting
points. (Also check out Gerard
Fonte’s four-part Enigma Machine
project, beginning in the June
2004 issue of Nuts & Volts. — Editor
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