The board calls for 200vac single winding along with the seperate secondary for the heater circuit. There is a zeener diode stack that would appear to limit the voltage to ~250v. The 6j1 tube filaments are in parallel on this circuit. The power supply circuit for the filaments calls for 6-12vac. Regulated back down to 6vdc.
6vac = ~8.4v peak, then subtract the diode drop. That probably hovers around the minimum voltage threshold to properly regulate 6vdc. I wouldn't be surprised if the heatsink is not even needed in that case.
Still waiting on the output caps to ship in. I wanted to try this circuit as a branch from the lower voltage 6j1 project here on the forum. Starting with stock as the baseline. I do have an "ALPS" pot from ali I could try if the stock one is trash. Though, if I'm going to put it in a case, It'd be interesting to replicate it as point to point. Using this circuit as a reference with whatever mods might be found useful. Maybe use a chinese 6z4 to rectify the high voltage. That could render the delay mosfet unneeded and get more glass in the circuit
@Kornbread said:
Would it be cheaper as far as s&h go to order a few of the trans? I'd be in for a few.
I could order some more. Any interest in the board kits too?
I used to DIY a lot of electronics when parts were easy to get and the things I wanted to have were expensive. This crossover has been sitting on the shelf forever gathering dust. I designed it, did the board layouts and put in a repurposed case I found surplus. The front panel was a cut down rack panel the I sanded the finish off for the brushed aluminum look.
@Ron_E said:
I used to DIY a lot of electronics when parts were easy to get and the things I wanted to have were expensive.
Ron
A big +1 to that. Nice clean pcb layout and metal film and good poly caps. Interesting choice to use stereo pots but only use one gang and have separate pots for each channel... very non-symmetrical listening space?
Comments
@DrewsBrews Would it be cheaper as far as s&h go to order a few of the trans? I'd be in for a few.
https://aliexpress.us/item/3256806251614199.html?spm=a2g0o.order_list.order_list_main.262.21ef1802mfVWlp&gatewayAdapt=glo2usa
The board calls for 200vac single winding along with the seperate secondary for the heater circuit. There is a zeener diode stack that would appear to limit the voltage to ~250v. The 6j1 tube filaments are in parallel on this circuit. The power supply circuit for the filaments calls for 6-12vac. Regulated back down to 6vdc.
6vac = ~8.4v peak, then subtract the diode drop. That probably hovers around the minimum voltage threshold to properly regulate 6vdc. I wouldn't be surprised if the heatsink is not even needed in that case.
Still waiting on the output caps to ship in. I wanted to try this circuit as a branch from the lower voltage 6j1 project here on the forum. Starting with stock as the baseline. I do have an "ALPS" pot from ali I could try if the stock one is trash. Though, if I'm going to put it in a case, It'd be interesting to replicate it as point to point. Using this circuit as a reference with whatever mods might be found useful. Maybe use a chinese 6z4 to rectify the high voltage. That could render the delay mosfet unneeded and get more glass in the circuit
I could order some more. Any interest in the board kits too?
I used to DIY a lot of electronics when parts were easy to get and the things I wanted to have were expensive. This crossover has been sitting on the shelf forever gathering dust. I designed it, did the board layouts and put in a repurposed case I found surplus. The front panel was a cut down rack panel the I sanded the finish off for the brushed aluminum look.
Ron
That looks great, Ron! It reminds me of older Conrad Johnson gear.
Sweet!
A big +1 to that. Nice clean pcb layout and metal film and good poly caps. Interesting choice to use stereo pots but only use one gang and have separate pots for each channel... very non-symmetrical listening space?
Ganged budget audio taper pots don't track very well.