Jeff K1NSS
01-06-2012, 02:17 AM
I got the idea from a picture posted by KB2VXA, of a Christmas tree topped by a lit-up 811A. That was shortly before Christmas. With little time left to do the same with a fallow 813 tucked away for a rainy day, I stepped back and thought Big Picture. How about a desktop 813 night light? Yeah, that's it, with a switched power take-off socket to remotely supply filament voltage to my tree toppper/vintage 813 valve NEXT CHRISTMAS. The pressure was off. But in the heat of the moment I Googled up the first apparently suitable filament transformer in sight and sent away toot sweet, before my Great Notion ebbed back to a Sea of Grave Reservations and I'd spend the rest of my life wondering what if?
The transformer arrived the day before Christmas. And while it was put aside for the duration, my project was never far from my thoughts. I thought I'd construct some kind of a housing for transformer to serve as a base for the pentode. Wood, metal, minimalist, artsy, fartsy, the base seemed a perfect storm of all but anything goes. Then I get a better idea. I could save myself a bunch of work if I could just find an appropriate box at my favorite local surplus store.
Well, I dropped by P&T Surplus in Kingston NY and found the box. Miraculously, it's a lamp power supply -- for a 6000 dollar Nikon microscope system boken up and sold a la carte. The supply was 20 bucks, and they threw in a couple of pin jacks and a genuine but empty Malden National box that I found in a tote of tubes.
So here's what I've got so far.
5122
Check this out. Before I opened it up at home, I figured I'd just gut it and use the nice solid front rocker switches and back outlets and whatnot.
5123
But check out what I found inside.
5124
Huh. Whole buncha voltages. No dedicated 10 tap, but 20 at 7A could be dropped to 10 with a resistor of suitable value and wattage, right? Don't everybody start throwing things. Of course, I could just remove the original transformer, mount mine in it's place, cut a hole in the top of the metal cabinet for the onboard tube socket, or make a wooden top, if I didn't feel like refinishing the metal case top. Everything looks pretty neat and tidy and secure, seems a shame to gut it, but perhaps some Islanders have some thoughts, once we get beyond the pointing and laughing. Have at it.
Jeff K1NSS
The transformer arrived the day before Christmas. And while it was put aside for the duration, my project was never far from my thoughts. I thought I'd construct some kind of a housing for transformer to serve as a base for the pentode. Wood, metal, minimalist, artsy, fartsy, the base seemed a perfect storm of all but anything goes. Then I get a better idea. I could save myself a bunch of work if I could just find an appropriate box at my favorite local surplus store.
Well, I dropped by P&T Surplus in Kingston NY and found the box. Miraculously, it's a lamp power supply -- for a 6000 dollar Nikon microscope system boken up and sold a la carte. The supply was 20 bucks, and they threw in a couple of pin jacks and a genuine but empty Malden National box that I found in a tote of tubes.
So here's what I've got so far.
5122
Check this out. Before I opened it up at home, I figured I'd just gut it and use the nice solid front rocker switches and back outlets and whatnot.
5123
But check out what I found inside.
5124
Huh. Whole buncha voltages. No dedicated 10 tap, but 20 at 7A could be dropped to 10 with a resistor of suitable value and wattage, right? Don't everybody start throwing things. Of course, I could just remove the original transformer, mount mine in it's place, cut a hole in the top of the metal cabinet for the onboard tube socket, or make a wooden top, if I didn't feel like refinishing the metal case top. Everything looks pretty neat and tidy and secure, seems a shame to gut it, but perhaps some Islanders have some thoughts, once we get beyond the pointing and laughing. Have at it.
Jeff K1NSS