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| GlassWare Audio Design | 9 | |
Typical Part Values () Parentheses denote recommended values |
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| 6CG7 & 6DJ8 | 6CG7 & 6CG7 | 12AU7 & 6H30 |
B+ Voltage = | 170V - 250V (250V) | 200V - 300V (300V) | 200V - 300V (150V) | |
Heater Voltage = | 6.3V or 12.6V | 6.3V or 12.6V | 12.6V | |
R1,5,6,7,12,13 | = | 1M | 1M | 1M |
R2,4 | = | 270 - 1k (640 5mA)* | 470 - 2k (640 5mA)* | 470 - 2k (741 3mA)* |
R3,9,10 | = | 100 - 1k (300)* | 100 - 1k (300)* | 100 - 1k (300)* |
R8,11 | = | 200 - 330 (291 10mA)* | 200 - 470 (240 10mA)* | 200 - 470 (74 30mA)* |
R15 | = | 87.3k | 83.2k | 76.5k |
R16 | = | 100k | 100k | 1 00k |
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| All resistors 1/2W or higher |
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C1 | = | 47µF* Film for | Same | Same |
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| 470µF* for | Not recommended | 470µF* for |
C2 | = | 0.47µF* Film or oil | Same | Same |
C3 | = | 10 - 1kµF, 10V Electrolytic "10 - 1kµF, 16V Electrolytic |
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C5 | = | 1 - 10µF* | " | " |
C6 | = | 0.047µF - 1µF* Film or oil | " | " |
C7,8,9,10 | = | " | Same | |
C11,12 | = | 0.1µF 160V(optional) | " | None |
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| *voltage rating must equal or exceed B+ voltage |
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(input) V2, V3 = | 6CG7, 6FQ7 | 6CG7, 6FQ7 | 12AU7, 5814, 5963, | |
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| 6189, ECC82 |
(output) V1, V4 = | 6DJ8, 6922, | 6CG7, 6FQ7 | 6H30 | |
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| 7308, ECC88 |
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Assembly
Before soldering, be sure to clean both sides of the PCB with 90% isopropyl alcohol, wiping away all fingerprints. First, solder the shortest parts (usually the resistors) in place, then the next tallest parts, and then the next tallest... Make sure that both the solder and the part leads are shiny and not dull gray. Steel wool can restore luster and sheen by rubbing off oxidation. If some of the parts have
Normally, such as when the PCB sits on the floor of its chassis, all the parts sit on the top side of the PCB (the top side is marked). If you wish to have the tubes protrude from holes on the top of the chassis (and to place the PCB within 1" of the top panel with the aid of standoffs), then all the other parts— ex cept the tube sockets— can be placed on the PCB’s backside; it is a
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