Happy jukebox day

 

re-placement high voltage transformer......need re-order high voltage transformer

new order high voltage transformer

re-placement

take off choke inductor
the space for dual rectifier cap.

 

P-P circuit implement......this case just could tie circuit to push pull amp.

CH-R 6JM6 PP playback sound 1

CH-R PP 6JM6 G1 shunt Imp.resistor tie to GND

CH-L PL519 PSE playback

CH-R 6JM6 PP playback sound 2

CH-L PL519 PSE playback

CH-R 6JM6 PP playback  sound 3

CH-L PL519 PSE playback

CH-R PP 6JM6 G1 shunt Imp.resistor tie to -32V playback sound 1

CH-R PP 6JM6 G1 shunt Imp.resistor tie to -32V playback sound 2

CH-R PP 6JM6 G1 shunt Imp.resistor tie to -32V playback sound 3

CH-R PP 6JM6 G1 shunt Imp.resistor tie to -32V playback

CH-L PL519 PSE playback

CH-R 6JM6 PP playback w RIAA (switch in DAC)

CH-R 6JM6 PP playback no RIAA (switch in DAC)

 

211 VT4C mono amp. L-ch SPK w noise..the check record

https://kao211.blogspot.com/2011/01/toy11-vt4c-211amp-5-verify-211-ac.html

recall ...211 VT4C plate voltage setup in 1265V w tube 211

recall ...high voltage capacitor explode

                                

                                                                

https://kao211.blogspot.com/2019/03/mono-mono-vt-4c-211-tube-amplifier.html

the record

                                      after repair ... L-ch playback check only

need re-order high voltage transformer...this case just could tie circuit to push pull amp.

                    Ref. Cyclotron Amplifier...because Cathode output the OT Imp.

                                setup up on high voltage transformer

this case just could tie circuit to push pull amp.

                                        to estimate amp.tube g１ voltage

last time

                                            

fix 2nd stage p-p voltage

shunt Ref. voltage to estimate amp.tube g１ voltage

PL519 Amplifier ...modify to Cathode output typology for nice matching w SPK

ref. typology

select signal tube 6922 vs 12Ax7

6922 Left channel

                                                12Ax7 Right channel 

take off PL519 40V heater transformer

for 6DJ8 6.3V heater 

make sure the -Voltage for gride bias

add 1st 6922 tube sockect

DAC feed in 1K wave then transfer to analog 1Khz waveform

1st stage 6922 gain tuning to balance p-pV

2nd stage 6922 gain p-pV w offset

Low noise tube for pre-amplifier

the resistor of low noise preamplifier 

benchmark we437a vs EH 6c45-pi

benchmark Japan 1970 low noise tube

modify PL519 amplifier...switch to VT-4C amplifier