Howard-Radio-Co-S250 电路原理图.pdf

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1、MANUAL OF 1939 MOST POPULAR SERVICE DIAGRAMS Howard Radio Company, 1731 Belmont Avenue, Chicago, Illinois Models; 225, S-225, 250, S-250, 260, S-260, 275, 275-C, 280. 15,000 - -oa. C5 til 7Sj 1 25.1 vvwyfy/vwviywwvvv diOCV l*l .OOi “Two Q) - ro / 700ACC. AXefAixr. - 2 7* 6.S TC. ji- i To /7 /C- J- S

2、 l/A7y7 the only differ- ence belnp- the cabinets In which they are mounted. These models have two band circuits covering the Broadcast Band 550 to 1700 KC and the so-called Police Band from 2 to 6.5 megacycles, having separate Antenna and Oscillator colls for each 3225 and S250 cover the Broadcast

3、Band 550 to 1700 KC and the short wave band 5.5 to 18 MC. , The models 0 and S260 have the same circuit or the 225, 3225 respective ly with the addition of the tuning eye tube to Indicate resonance. , , The models 275C and 280 are the same electrically, covering 3 bands, 550 to 1700 KC,-1.7 to 5.5 M

4、C, and 5.5 to 18 MC. 1 The I F.s are aligned by the usual system of feeding the intermediate o S uflaSshould be very oarelully peaKed to renaSe leS crltlcal-d eatly affect the performance of the set. These are trimmers number T8, T9, TiO, Til. , The Sensitivity of the I. F. stages will be 25 to 50 microvolts or better for Iwanoutput as possible from the test osclllat m the various adjustments. COMPILED BY M. N. BEITMAN SUPREME PUBLICATIONS IMP 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库 RadioFans.CN