Page:April 1916 QST.djvu/22

 

(1) Shows panel receiving set with audion detector and two step amplifier for waves from 600 to nearly 10,000 meters. Cabinet containing transmitter of 1 to 1½ KW. at left, only end with meters etc. visible. Novel features:&mdash;Vertical row of four telephone switches, just at left of audion bulbs, allow instant amplification of signals without changing phone connections, or other adjustment, one or two amplifications or single detector, or vice-versa., No interference with sensitiveness when these switches are in neutral position. Two telephone switches, center top, place loading coil, both primary and secondary, in circuit for waves over 2500 meters. These. loaders in no way effect sensitiveness of coupler when switches are in neutral position. Telephone switch, middle near bottom, throws wave mater into circuit on audion, waves up to 3,000 meters, receiving, measurable. This switch also prevents loss of sensitiveness when in neutral position. Aerial switch of special construction breaks both aerial and ground circuits when transmitting, preventing any POSSIBLE trouble with receiver, also starts and stops rotary, one movement, one wire common to bath transformer and motor of rotary. This set not efficient under 600 meters receiving.

(2) Eighty foot spruce pole, set in concrete, supporting one end of two wire aerial. Two wires spaced about 6 feet apart found to be very practical. Insulation, two ten-inch electrose insulators in series, each end. Standard phosphor bronz [sic] wire. Bamboo spreaders. Aerial held taut by 60 lbs. cast iron counterbalance, this rises and falls during storm, relieving strain.

(3) Special loose coup1er for amateur waves. Tunes with above aerial only up to 600 meters. Wire on primary and secondary wound with one-sixteenth separation between turns. Secondary inductance not adjustable, but coupling variable, minimum wave 250 meters, above this condenser added in shunt with secondary, or variometer in series with secondary. Capacity in secondary of audion circuit cuts down signals. Excess wire in primary of ordinary loose coupler re-radiates energy and cuts down signals.

(4) Oscillation transformer of transmitter. Note loose coupling and also heavy copper strip used in closed circuit. Practically no inductance on this instrument except that in use; this gives more satisfactory results than usual practice. Oscillating transformer set on top of cabinet which contains transformer, condensers, and rotary so placed to make all leads very short, longest one not over fourteen inches. Note:&mdash; One wave, sharp, radiating three amperes better than set which may have three waves, radiating respectively, 2½, 1½, ½, or total 4½ amps. Receiving set can only take advantage of radiation on ONE wave; hence, often a looser coupling, and decreased radiation in amps, if set is tuned sharp, gives greater transmitting distance.

Transmitting range of this station well over 1,000 miles, night work, winter. Receiving: undetermined. but well over 3,500 miles.

Note:&mdash;This set receives continuous wave signals, and acts as oscillator, on ALL wave lengths, by changing one connection on audion circuit and adding small variable condenser.



The picture shows the exterior view of the Pennsylvania State College Radio Station.

