Electrical news and engineering . rame. The inside portion of the send-receive switch, in thelower part of Fig. 3, is idle in the receive position Y, hut thesend position X at 21, it completes the 1,500 volt sup-ply current to the plates P and P of the pliotrons. At52 it connects the primary of the microphone transformerP, to the microphone terminals 28 and to the buzzer I).These connections are opened in the receive position. There are three positions for the signal switch. Thehist. X, is for continuous wave telegraphy. In this positionthe connections made in the second and third positio
Electrical news and engineering . rame. The inside portion of the send-receive switch, in thelower part of Fig. 3, is idle in the receive position Y, hut thesend position X at 21, it completes the 1,500 volt sup-ply current to the plates P and P of the pliotrons. At52 it connects the primary of the microphone transformerP, to the microphone terminals 28 and to the buzzer I).These connections are opened in the receive position. There are three positions for the signal switch. Thehist. X, is for continuous wave telegraphy. In this positionthe connections made in the second and third positions areopened. The second position Y is for telephony; the insideportion of the switch I the upper part in hit;. 3) connectsthe microphone to the microphone battery, and at 51 theoiitsnle portion (in the lower part of Fig. :; i completes thefilament circuit for modulating valve and short circuits thekey at 47. In the third position, the switch connects at30 A the buzzer to the microphone battery, and at 51 keeps Hey K-i Battery Fig. 3—Wiring diagram showing the function of the cha tap in the 1 dun meter position to (he grid condensei Iwith its leak resistance K,. The actual wiring of the set diJfers slightly from this, for it was found that the same taproil was correct for both wave lengths. For thisreason, there are but two taps on (he lower portion oi the ! I he lirsi of these is pled rectly to the grid con i and does not go through the wave length marked 12 shorl circuits one end of the in (he 600 meter position and removes the short circuit;n the 1,600 metei position The switch marked XV m Kig. • serves I nnecl itenna V to tin l mittei in the send position , \ | anc] ,,, ,|M. ,. . ? - position I Y i. In the filament of the modulating valve lighted, removing theshorl circuit from the key. The position of the switches in Fig. :: does nol pond with their location on the set. All three swi are buill to stand •> maximum of 10,000 \o
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Keywords: ., bo, bookcentury1800, bookdecade1890, bookidelectricalnewsen28donm
