. QST . power amplifier. The stage ismounted on a small subchassis underneath the receiver. 3) .4dd 4) -Add shunt noise limiter (1N34). 5) Add and gain controls. C) Replace all 12-volt tubes with their 6-volt equiva-lents. The 12A6 was replaced by a 6V6. 7) Rewire all heaters in parallel. 8) Replace the antenna trimmer capacitor with a unitthat is screwdriver-adjusted from the side. The capacitorthus released was used as a pitch control. 9) Add speaker and matcliing transformer. Details Lets take each feature and study how it canbe accomplished. The frequency stability
. QST . power amplifier. The stage ismounted on a small subchassis underneath the receiver. 3) .4dd 4) -Add shunt noise limiter (1N34). 5) Add and gain controls. C) Replace all 12-volt tubes with their 6-volt equiva-lents. The 12A6 was replaced by a 6V6. 7) Rewire all heaters in parallel. 8) Replace the antenna trimmer capacitor with a unitthat is screwdriver-adjusted from the side. The capacitorthus released was used as a pitch control. 9) Add speaker and matcliing transformer. Details Lets take each feature and study how it canbe accomplished. The frequency stability is exceptional in thisunit. The crystal-controlled high-frequency os-cillator, together with the excellent stabilityfound in these receivers, makes receptioneasily possible even while driving over roughroads. The BC-453--\ has an intermediate freciuencyof 85 kc. and has six tuned circuits. This givesgood selectivity. The selectivity with minimumcoupling in each transformer is sharp. A BC-453-A with a few revisions makes a good tun-able amplifier for a mobile receiver. One is shownhere tucked under the dash. March 1955 33 enough for reception. (The coupling can bevaried by unscrewing the knurled cover and ad-justing the fiber rod.) Up position is minimumcoupling. More coupling is desiral)le for ( for exalted-carrier reception). The noise CONVERTER6BE6 an gain control. This was retained in the finaldesign for , and an audio control was addedfor normal reception. In the writers in-stallation, this receiver is independent of thebroadcast set except for the speaker. TO OBC-453
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectradio, bookyear1915
