Ink's fancy new old stock Vacuum tube amplifier.
Based on the classic Dynaco ST70 Class B super-linear audio amplifier, the design features a pentode preamp, push-push Class B transformer coupled, double linearized output stage.
Built with modularity and expansion but also tradition in mind, the amp is entirely analog and free of disgusting semiconductors but has space in mind for adding a nixie tube-bargraph based digital VU meter and
Power Transformer Specs:
PA521 Specs:
Primary:
Blue to Blue 240V 50Hz @1A
Secondary:
Green to Green 6V3 @2A w/ CT Green-Yl
Brown to Brown 6V3 @2A w/ CT Brown-Yl
White to White 5V @ 4A
Red to Red 720V @300mA w/; CT Red-Yl and 55V Bias Red-Bl
Windings
Winding Diagram Cutout for the power Transformer:
(Values need to be verified )
Modified Transformer Specs:
Primary:
Blue to brown: 230V 50Hz @1A
Secondary:
Green to Green 6V3 @2A w/ CT Green-Yl
Brown to Brown 6V3 @2A w/ CT Brown-Yl
White to White 5V @ 4A
Red to Red 720V @300mA w/; CT Red-Yl and 55V Bias Red-Bl
Windings
Primary
| from | to | turns |
|---|---|---|
| blue | brown | 530 |
Secondaries
| from | to | turns | old | Target Voltage @ 230V in |
|---|---|---|---|---|
| Filament | ||||
| grey1 | grey-yl | 7 | 7 | 3,15V |
| grey-yl | grey2 | 7 | 7 | 3,15V |
| Power | ||||
| red1 | red-bl | 703 | 674 | 305V |
| red-bl | red-yl | 127 | 121 | 55V |
| red-yl | red2 | 830 | 795 | 360V |
| 5V | ||||
| white1 | white2 | 12 | 11 | 5V |
| Filament | ||||
| brown1 | brn-yl | 7 | 7 | 3,15V |
| brn-yl | brown2 | 7 | 7 | 3,15V |
| Total | 1700 (~306m) |