kahlfin1k
Well-Known Member
According to the manual I have the instructions for setting the bias are essentially the same as the MKIII which uses KT88s instead of EL34 (only the II uses a 12 instead of 11.2 ohm cathode resistor).
This would mean that with the nominal plate voltage (per manual) of 460 and 1.56V across the cathode resistor the EL34s would be dissipating almost 30 watts! That can't be right! Obviously that's about perfect for KT88 in class AB (as in the MKIII) but that's definitely red plating territory for EL34s.
Here's the manual, http://www.thehistoryofrecording.com/Manuals/DynaCo/Dynakit_Mark_II_Manual.pdf note where it says on page 10 seccond paragraph, in the same sentence EL34 and cathode current of 130 (65 per tube) which would give 29.9 watt dissipation at 460V plate voltage.
Am I missing something here? Is this just a totally incorrect manual or were people actually running these that hot?
This would mean that with the nominal plate voltage (per manual) of 460 and 1.56V across the cathode resistor the EL34s would be dissipating almost 30 watts! That can't be right! Obviously that's about perfect for KT88 in class AB (as in the MKIII) but that's definitely red plating territory for EL34s.
Here's the manual, http://www.thehistoryofrecording.com/Manuals/DynaCo/Dynakit_Mark_II_Manual.pdf note where it says on page 10 seccond paragraph, in the same sentence EL34 and cathode current of 130 (65 per tube) which would give 29.9 watt dissipation at 460V plate voltage.
Am I missing something here? Is this just a totally incorrect manual or were people actually running these that hot?
