. QST . -^ ■••300 ♦SX5. + H,V. +C -C -B . Fig. I — Viiring diagram of the transmitter. The section above the dashed line is the Bandbox frequency-multiplier unit. All resistors Yl watt unless otherwise specified. Capacitor values below pi. are in /i/if. capacitors except C? are 500-volt disk ceramic; others are mica. 26 QST for Fig. 2 — Power-supply and t-larnp-tiibe circuit. Li — Swinging choke, 5-25 henrys, 20-200 ma. (Triad Ii, I2 — 115-voli pilot lamp. ,4 ,„ , ,„„ ,~ . Ti—Plate transformer; for 750 v. , 225 ma. L2 — hmoothmg choke, 10 henrys, 200 ma. (Iri
. QST . -^ ■••300 ♦SX5. + H,V. +C -C -B . Fig. I — Viiring diagram of the transmitter. The section above the dashed line is the Bandbox frequency-multiplier unit. All resistors Yl watt unless otherwise specified. Capacitor values below pi. are in /i/if. capacitors except C? are 500-volt disk ceramic; others are mica. 26 QST for Fig. 2 — Power-supply and t-larnp-tiibe circuit. Li — Swinging choke, 5-25 henrys, 20-200 ma. (Triad Ii, I2 — 115-voli pilot lamp. ,4 ,„ , ,„„ ,~ . Ti—Plate transformer; for 750 v. , 225 ma. L2 — hmoothmg choke, 10 henrys, 200 ma. (Iriad ,., . r.^,.„, C-16A). (Merit P-31d9). — 3-pole 2-po8ition ceramic switch, nonshorting T2 — Filament transformer: 5 v., 3 amp. and v., (Centralab 2507). 6 amp. (Stancor ). consists of four turns of B & W Miniductor , and resonates in the 10-meter bandwhen LeB is shorted out b\- running the con-tactor all the way down to the end. Operationon 15 meters through 80 meters is accomplishedwith Lba working in series with Lgb, with Leebeing adjusted for more and more inductanceas we progress from 15 to 80 meters. Lee consistsof 13^ inches of B & W No. 3907, which, inconjunction with Lga and Lgs, vvill resonate on160 meters. It was removed for the photographsbecause it hid too many of the other
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectradio, bookyear1915
