Ciao perdonate il mio inglese sto costruendo un clone del dynakit st 35 riscontro un problema, non riesco a capire sul pin n 6 del triodo di ingresso 7247 ci sono 52 vdc mentre la tabella schematica riporta 112vcc, grazie per eventuali consigli
Translation:
Hi, forgive my English, I'm building a clone of the Dynakit ST 35, I'm having a problem, I can't understand on pin 6 of the 7247 input triode there are 52 VDC while the schematic table shows 112 VDC, thanks for any advice
English please.
Hugo
Moderation team
Hi, forgive my English, I'm building a clone of the Dynakit ST 35, I'm having a problem, I can't understand on pin 6 of the 7247 input triode there are 52 VDC while the schematic table shows 112 VDC, thanks for any advice
English please.
Hugo
Moderation team
Last edited:
Doublecheck your resistor values. Also check that the 7247 tube is a real 7247 or possibly JJ ECC832
Translation:
300K Resistor Definitely ECC832 JJ Valve
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Hugo
300K Resistor Definitely ECC832 JJ Valve
Google translate can help to post in English. Please do so.
https://translate.google.com
Hugo
This indicates that the first triode draws too much current ( Vcat= 1.8V )
Two reasons : the grid is not grounded but free floating. Check this( you could ground pin 7 to ground )
Or the tube is the 823 model, check by temporarily replacing with a ECC83
If you install a ECC83/12AU7 in the same socket i suspect that the voltages on
plate and catode is according to the dynaco manual ( 112V and 0.8V )
To be gente of the ECC83 you could temporarily disconnect the R7 and R6 resistors.
Two reasons : the grid is not grounded but free floating. Check this( you could ground pin 7 to ground )
Or the tube is the 823 model, check by temporarily replacing with a ECC83
If you install a ECC83/12AU7 in the same socket i suspect that the voltages on
plate and catode is according to the dynaco manual ( 112V and 0.8V )
To be gente of the ECC83 you could temporarily disconnect the R7 and R6 resistors.
hello Petertub thank you for the suggestions,you turned on the light bulb.incredible I inverted the 2 triodes contained in the ecc832,After so many years of self-construction I still make these mistakes, unfortunately the years are no longer green Thanks again
When you get it up and running, we want to hear how the very build of a clone sounds.
And, please list the speakers, and the signal sources.
Decades ago, my brother built a real Dyna ST35 kit. It sounded great.
And, please list the speakers, and the signal sources.
Decades ago, my brother built a real Dyna ST35 kit. It sounded great.