> Does any know the E235L tube. Look like a mini EL34?
No, and it doesn't really seem to be a cut-down EL34.
It is scaled for lower Mu, and generally low-voltage low-impedance operation.
The Betriebswerte on the bottom of page 2 shows a perfectly good 30 watt condition. It is very Class B: for hi-fi use you might want to reduce the G1 bias to get the idle current up around 50mA-60mA per tube. Or maybe a 250 ohm common cathode resistor. The 250V Vp and 170Vg2 is a little awkward considering the wide range of G2 current: a regulator may be wise. Or let the G2 live at 250V and increase G1 bias to keep the current down: this gives lower gain but more tolerance for odd-impedance loads like speakers.
If you can't find a 3K transformer, use a 6K and re-label the speaker taps.
No, and it doesn't really seem to be a cut-down EL34.
It is scaled for lower Mu, and generally low-voltage low-impedance operation.
The Betriebswerte on the bottom of page 2 shows a perfectly good 30 watt condition. It is very Class B: for hi-fi use you might want to reduce the G1 bias to get the idle current up around 50mA-60mA per tube. Or maybe a 250 ohm common cathode resistor. The 250V Vp and 170Vg2 is a little awkward considering the wide range of G2 current: a regulator may be wise. Or let the G2 live at 250V and increase G1 bias to keep the current down: this gives lower gain but more tolerance for odd-impedance loads like speakers.
If you can't find a 3K transformer, use a 6K and re-label the speaker taps.
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