Rock-OLA_conversion 电路图 维修原理图.pdf

收音机爱好者资料库 Ra d i o Fa n s .CN 收音机爱好者资料库 Ra d i o Fa n s .CN A 0.1uF 200 100K 0.1uF 100K 47K 1K Jensen 12 field coil SPEAKER (8 OHMS) 4 5 8 3 4 8 5 3 4 B 5 6 2 1 3 220K 3.9K 4.7K 47K 50uF 1K 6SN7 6L6 6L6 BB 500pF 75pF 22K HF Horn HI-FI 270K 4.7K C 1M25uF Input C 4 5 6 2 1 3 10K 560 .002 .47 .25 VOL 10K 47K 12K 22K BASS 250K TREB 250K .01 .02 500pF .005 6SN7 120VAC 5 VAC 202020 1540 with CT6800 A 385 VDC B 300 VDC C 240 VDC 375-0-375VAC 6 8 2 4 5U4 120VAC 6.3 VAC filaments V4 V3V2V1 Hum Balance2 7 8 7 8 7 2 7 20 5000 Field Coil on speaker This transformer is located on a separate control chassis. It has multiple secondaries that power various other circuits inside the jukebox. The 6.3VAC winding is used only to power the amplifier tube filaments. Rock-Ola model 1442 jukebox amplifier This simplified schematic is electrically correct, but has purposefully omitted interconnection plugs and jacks to make the schematic easier to understand. The AC primary circuit, fuses, switches, relays, etc. have been omitted for the same reason. 8 4 OT also has a separate 500 secondary 2uF 5 Manufactured in 1954 收音机爱好者资料库 Ra d i o Fa n s .CN A 0.1uF 200 220K 0.1uF 220K 47K 1K Eminence Big Ben 15 (8 OHMS) 4 5 8 3 4 8 5 3 4 B 5 6 2 1 3 220K 3.9K 47K 50uF 1K 6SN7 6L6 6L6 BB 22K 270K 4.7K C 25uF C 2 1 3 4.7K 6SN7 Rock-Ola Model 1442 Jukebox Amplifier Conversion 8 4 OT also has a separate 500 secondary 270K .022 1M 1MA VOL 250KA 250pF .1 .047 110K 250KA 6.8K TREBLE BASS 5 4 6 25uF Fender AB763 Tone Stack 510/1W 510/1W RAW 250KA 1M 33K 102 vdc 0 vdc0 vdc0 vdc 4.6 vdc4.8 vdc 105 vdc 102 vdc 4.4 vdc 270 vdc 110 vdc 0 vdc 0 vdc 394 vdc 382 vdc 392 vdc 382 vdc 360 vdc360 vdc384 vdc384 vdc 402 vdc 384 vdc 27.8 vdc 6SN7 Conversion by Steve Luckey, 08/20/09 6.3 VAC filaments V4 V3V2V1 Hum Balance2 7 8 7 8 7 2 7 120VAC 5 VAC 202020 1540 with CT10K/2W A 402 VDC B 384 VDC C 360 VDC 375-0-375VAC 6 8 2 4 5U4 20 5000 30W Brown *300 VDC*240 VDC *Lower voltages with Brown switch closed LINE GROUND 3 AMP SLO BLO POWER T1 T2 T3 *394 VDC V1AV1B V2AV2B oConverted V1B cathode follower to a gain stage identical to V1A. oReplaced James tonestack with Fender AB763 tonestack plus Raw control. oRemoved Hi cut filter at input to split phase inverter/driver. oRemoved 75pF cap in NFB loop. oReplaced 100K grid resistors for 6L6s with 220K. oInstalled 510 screen grid resistors. oReplaced field coil with 5K 30W resistor and added Brown switch. oReplaced 6.8K dropping resistor for Node C with 10K 2W resistor. oAdded onboard filament transformer T2. Conversion notes