[Lowfer] A little more antenna work done today - kinda long reading

[Ralph W5JGV]

> the resistance measured 4 Ohms...BTW the coil is wound
> with around 320 feet of #16 insulated solid wire to get the 2.3mH
> of Inductance. The 4 Ohms reading seems a little low to me, and
> after thinking about the situation for a few minutes, it dawned on
> me; I had to use around 30 feet of clip leads connected together
> to span the antenna length, and the meter itself I'm sure has some
> amount of internal resistance, so I figure that when I parralled
> the meter and wire to the antenna, I cut the DC resistance lower
> than it actually is. Most likely the resistance will come closer
> to around 7 to 9 Ohms.

Hello Andy,

Methinks there's an error somewhere.

#16 copper wire has a DC resistance of about 4.094 Ohms per 1000 feet, so
320 feet should measure about 1.31 Ohms.

Check your coil by itself and see what it reads.  If it's reading a lot
different than 1.3 Ohms, check your meter.  Shorting the meter leads
together with the meter set to the low Ohms range should result in a reading
of Zero Ohms.

>From your description, you have the loading coil, the antenna mast, the
ohmmeter and its leads, and a bunch of clip leads, all connected in series
with each other.  If that is so, then all the various resistances add
together.  You should read the resistance of the loading coil, plus the
antenna mast resistance, plus the clip and meter lead resistance as the
total value.

You should be able to connect all the clip leads in series and then connect
the test meter leads to the open ends of the clip leads.  That way you will
read the resistance of all the leads.  You can then subtract that reading
from the reading you get when you connect the antenna in the test loop.  You
may be able to just use the meter Ohms Zero adjustment pot to calibrate the
meter to read zero Ohms when the clip leads and the meter are all connected
in series, but without the antenna connected.  Then, when you insert the
antenna in the test loop, the reading you get will be the antennas DC
resistance.

73,

Ralph  W5JGV - WD2XSH/7