Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: vetmed on February 04, 2012, 04:58:35 PM

Title: Current limit for 6.3 V winding?
Post by: vetmed on February 04, 2012, 04:58:35 PM

I see from some of the recommended tube subs that the current can exceed 3 amps e.g. 12bh7 and 6080. What is the maximum current available from this winding?

Robert Lees

Title: Re: Current limit for 6.3 V winding?
Post by: Paul Joppa on February 05, 2012, 07:29:12 AM

It was designed for 3.5 amps total. That's pushing it, the filament winding is the hottest of the windings. I do not recommend exceeding 3.5 amps by any amount at all.

Title: Re: Current limit for 6.3 V winding?
Post by: grufti on February 05, 2012, 07:58:58 AM

I decided to add another transformer for the filaments when I switched to the E80CC / 5998 tube combination. It is a tight squeeze under the hood, but it fit and it works great for me.

It will hopefully pay off too, when I modify the Crack for the higher current operating point that is being talked about.