The aerial or antenna is of the "loop-type" consisting of six hard drawn No. 12 copper wires 100 feet long attaclied to ten foot spreaders at each end extending in a northwesterly direction. Each of the six wires is insulated from the spreaders by three glazed porcelain ball insulators joined in series. Two strain insulators having a tensile strength of 1,000 pounds suspend the aerial between two masts, besides providing a further insulation of 75,000 volts. One of the masts is a steel pole erected on the roof of the house, the top of which is 43 feet above ground; On high ground back of the house, a 40 foot steel tower has been erected having a 16 foot 4 x 4 securely mounted at the top that gives the aerial a height of a little over 50 feet at this end. On account of the tower being on high ground, there is a difference of nearly 30 feet in elevation of the two ends.
As to its details of construction, it closely resembles the towers erected on the Lackawanna Railroad Station, and the Boston Herald — but the "United Wifeless Station" (WDR) in Detroit, Mich., is the one it is really designed after, althouph on a much smaller scale. The "rat tail" consists of six phosphor bronze wires of seven strands, of No. 22 each, that load from one aerial to two lightning arresters on the exterior of the building. From the lightning arresters two lengths of high tension pirelli cable serve as "lead-in" wires, connecting the aerial with the apparatus in the operating room.
The apparatus is connected with the earth by means of a heavy stranded copper wire composed of 480 No. 30 B&S, gauge wires — the equivalent of a No. 4 single copper conductor. This is soldered to the ends of nine discarded boiler tubes taken from one of the government boats. The tubes are 12 feet long and are laid fan shape in moist ground, giving an exposed surface area of 100 square feet. This gives a ground connection nearly, if not equally as efficient as a connection to city water main — the absence of which made necessary this extra labor.
The receiving apparatus consists of two rotary variable condensers and one adjustable tin foil condenser contained in a cabinet made of bird's eye maple, stained rnahogany with a loose coupler and universal detector mounted on top, together with various switches, etc., that enables any of the instruments to be cut in of out of circuit or to be adjusted to various wave lengths and capacities as desired. The receiving transformer has a range of about 600 meters, but for stations using longer waves than this, a large loading coil (double slide tuning coil) is used that increases the range to about 5,000 meters. This is a coil containing 630 feet of wire wrapped on a cylindrical form 18 inches long and 6 inches in diameter. In the construction of the loose-coupler, red fibre is used throughout; also in connection with the variable and fixed condensers. The variable condensers consist of 16 stationary and 15 movable aluminum plates, while the fixed condenser consists of 64 sheets of tin foil made adjustable by steps. In the detector, galena (found in this locality) has so far proven to be the most sensitive mineral tested out for long distance work. Several pair of Brandes receivers — including their Navy, Transatlantic and Superior types — complete the receiving set, and the extra pairs of phones have proven invaluable a great many times when other amateurs and friends have come around to listen-in.
The transmitting apparatus is of the switch-board type. At present it is in course of construction and will probably be some little time before every detail is completed, although actual tests will be possible some time in February. The board is inch and a quarter light pink. Tennessee marble 55 x 36 inches divided into three panels and supported by an iron frame above a table on which the receiving apparatus sets. The center panel is 25¾ inches wide; the side panels, 15⅝ inches. Only the center panel is used for the mounting of apparatus pertaining to the transmitting set.
When completed, the set will consist of a one kilowatt closed-core magnetic leakage transformer having 5 primary variations of power operating on 220 volts and a secondary potential of 12,000 volts; a compressed-air spark gap with air pressure gauge - maximum pressure, 50 lbs. together with high pressure pump conveniently located for use while at the key; an 8 x 10 glass plate and a three-fold protective devide consisting of a double condenser, graphite resistances and 3 point gap. Two pilot lamps, placed above the meters serve to illuminate the entire board. All switches, fuses, meters and apparatus, requiring adjusting are mounted on the front of the board while the transformer, spark gap, condensers and oscillation transformer are mounted on iron frame work made of pipe to form an adjustable shelf in a manner common in switch-board construction. Low down in the cen-condenser in 4 sections — each section consisting of 12 plates and the whole connected in multi-series, adjustable in steps of 6, 8, 10 and 12 plates from the face of the board (not shown in picture as this has only recently been completed); a series condenser; an oscillation transformer — a Blitzen Radio coupler revised to make possible its adjustment from the face of the board; (also not shown in the picture) three "Kermel" switch-board meters — ammeter, voltmeter and radiation ammeter 1), of the board is placed a "United Type" or loop-aerial switch, so far in receiving, however, the best results have been obtained with a plain straight-away connection. Two 15 ampere, 250 volt refillable cartridge fuses protect the entire board.
Two 6 ampere, 250 volt cartridge fuses protect the condensers provided to carry off the small charges from kick-backs; while the other fuses are provided to protect the voltmeter and pilot lights.
1) В оригинале эта фраза напечатана так: "... switch-board meters — ammeter, voltmeter and radiation ammeter, ter of the board is placed..." (прим. составителя).
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