ANTENNAS AND METEOROLOGICAL INSTRUMENTS

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Antenna tuner.  Variable condenser and plug-in inductor to resonate the open wire antenna feeders to a pure resistance, so that radio transmitters can be efficiently tuned to full output power when connected here.  Feeders can be series tuned if low resistance, parallel tuned if high resistance to provide selectivity from harmonic radiation.  Tuneable from 550 kc - 56,000 kc with the appropriate inductor.

Lightning switch to ground (up) to disconnect the feeders from the equipment for protection during electrical storms and to discharge induced electrostatic voltages.  Everthing is insulated for 100,000 volts breakdown.
Open wire feeders entrance to house.  Spacing of the feeders is 6 inches, resulting in 600 ohms impedance.  Custom window installation features double walled wooden panels with air insulation between, and porcelain feedthroughs installed on either side.  Note the rain drip wires hanging on the curved portions of the feeders to prevent water from entering the house.  White insulators support a Marconi inverted L antenna.  Visible at the bottom is the RG-8 coaxial cable for a grounded Marconi antenna, and the heavy ground wire attached to a cold water pipe.

Antenna feeders and inverted L antenna lead proceeding toward the back of the house.
Above the transmitting antenna feeders is a short parallel set of heavily insulated wires between the house wall and the family room chimney.  The earth's electric field potential difference is measured between these wires and registers on a sensitive electrometer connected to them.  Since the earth is negatively charged, during fair weather the potential is typically 100 V/m positive (going up from the ground).  Small cumulus clouds passing directly overhead momentarily reduce this voltage due to their local negatively charged cloud bases.  During thunderstorms, the potential reverses and swings wildly to 10,000 V/m negative.  The atmosphere is a very dynamic environment, and it is fun to watch the electrometer readings!  Dr. Bernard Vonnegut (brother of novelist Kurt Vonnegut) was a physicist who did extensive research measuring the electric field of thunderstorms and rain.

Feeders proceed along family room roof.  Marconi inverted L now proceeds as a top capacitive loading section (in the old days, ~1914, multiple wires were used due to the very low frequencies spark transmitters used).  Taylor weather instruments - anemometer and wind vane are mounted on the chimney, with remote reading console inside the house.
The open wire feeders center feed the Hertz antenna.  The Marconi inverted L antenna can be seen also.

The main Hertz transmitting antenna, facing west.  This antenna system is extremely efficient in radiating all rf power fed to it.
Grounded Marconi antenna, 27 ft. height, base loaded, constructed of two 12 ft. copper water pipes, one 3/4" ID, one 1/2" ID.  This antenna is fed with RG-8 coaxial cable.  The chain link fence is part of the ground system!  Currently tuned to the 7000-7300 kc band, very broad bandwidth.  The white Stevenson weather enclosure is home-made to NWS standards and contains antique weather instruments.

Inside the weather enclosure are a recording thermograph and a recording hygrograph.  These are 7-day clock-wound rotating drum mechanisms.  A sling psychrometer (not shown) measures humidity to within 1% using the wet-dry bulb thermometer table.
A Taylor "stormograph" barograph, Taylor barometer, and a cloud chart complete the complement of weather instruments needed to make accurate local forecasts often surpassing generalized radio forecasts.

General Radio Co. d-c amplifier and electrometer with 1011 ohms input impedance for measuring the electric field of the atmosphere above the earth.  Storm events can be captured on the Varian chart recorder.