KIT 1:
Amplifier for cap and pilotage of final stages to transistors, the outline is practically the stage pilot of a Williamson, famous for its musicalità, employs alone triodi, with dedicated transformer of escape, can directly pilot in current one to transistor to the B and thanks, final stage windings with gain in the highest current (* 1).
List component (council resistances from 1w and condensers of quality)
| R1 | R2 | R3 | R4 | R5 | R6 | R7 | R8 | R9 | R10 | R11 | R12 | R13 |
| 1M | 10K | 2.2K | 100K | 47K | 47K | 22K | 47K | 470K | 470K | 1.2K | 1.2K | 2.2K |
| C1 | C2 | C3 and C4 | C5, C6 and C7 |
| 0.2mf 250v polyester | 4700pf polyester | 0.2mf 400v poliest. | 33mf 350v elettr / / 0.1 mf 400v polyester |
Construction:
V1 and V2 are double triodi ECC82, the transformer of escape are realized with nucleus to C see figure,
the windings are following: head physician 3000+3000 coils of enameled wire d = 0.125 milimeter -
Secondary: C.R. 900 0.125 coils d = milimeter - cap 230 0.2 coils d = milimeter - To 8 0.8 coils d = milimeter - B 8 0.8 coils d = milimeter.
Some observations on this transformer that is the heart of all the plan: for the realization of an amplifier for cap the indicated windings as To and B they are superfluous, they serve in fact for the direct pilotage of a final stage transistor (optional) that it concurs to realize to low cost power amplifiers of high power maintaining vacuum tubes characteristics.
The feeding transformer has three secondary ones: 180 V 50 mA for the anodic one, 6.3 V 1A for i filaments, 2.5 V 1 To for the polarization of the eventual successive stage, the anodic one go straightened with a bridge realized with 4 diode valves 1N4007, the 6.3 volt of filaments do not go straightened, but ohm between filament must remember to connect a resistance from 100 and mass, the other secondary one goes second used the indications of the specific plan of the final stage that is wanted to be realized.
(* a 1) relationship of transformation therefore is elevated that it is found for experimental way, embezzling gradually coils to the transformer realized in base to the calculation, after tests of I listen not of all the satisfactory ones, to the end the result has been thrilling, in truth a relationship of transformation 375 to 1 for theoretical way would very not have come outside easy, this is the small secret that is to the base of the hybrid amplifiers (excluded a version of ELLA) that I have realized and that soon I will introduce on these pages.
(* 2) I am working to the realization of a printed circuit, in version mono, completely independent, with all the members, comprised the transformers, hardly ready I will introduce the photos.