Bottlehead Forum

Bottlehead Kits => Stereomour II => Topic started by: Tom-s on February 16, 2021, 06:52:51 PM

Title: SII > 245V input voltage
Post by: Tom-s on February 16, 2021, 06:52:51 PM

Can I wire my SII for more than 245V input voltage? This is sometimes the case and with 235-245 settings my voltages are a bit higher than i'd like (especially with the EML 5% heater tolerance) I know i can separately change the heaters and high voltage; but this may be more convenient.

Title: Re: SII > 245V input voltage
Post by: Paul Joppa on February 16, 2021, 07:38:57 PM

You can't; there only so many taps on the power transformer.

Wired for 235-245 just means it's wired for 240 volts nominal. Ten percent high is a traditional maximum deviation for tube gear, and perfectly safe in Stereomour for 90% of tubes. That would be at 264 volts.  (5% would be 252v. 245v is only 2%.)

If your average mains voltages differs from 240v by more than you are comfortable with, then it's time to adjust the filament dropping resistors. That's what they are there for!