Voodoochile
Supafly & The Funky Pimps
- Joined
- Sep 13, 2002
- Posts
- 4,883
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- 14
<< pics added of finished potted trafos down in post #17>>
Finally am making some headway on my custom Ear+HD. More details on the overall project to follow later, but this is the PSU portion of this trip. I disconnected the B+ in my existing amp and lashed this PSU to it; and borrowed the filament power from the amp for the PSU's rectifier heat.
I've been running a bunch of sims for a while, and finally breadboarded (plywood-ed?) it this weekend with a solid state bridge. It worked very well, so I continued on tonight by replacing half the bridge with a tube rectifier as per my end plan, and fired it up (no pun intended).
Make sure the kiddies are asleep before you try this at home...
Detail shot of rare multi-ply fir circuitboard:
The original Ear+HD uses four FREDs and a C-R-C-R-C filter in the PSU. This dicey looking rig is a hybrid bridge made from two FREDs, the tube rectifier (+ out) and is now C-R-C-L-C-R-C. The LC filter was a later thought, after scrounging up a nice NOS Thordarson choke that was suitable. The voltage needs to be adjusted about 14 volts higher... I don't have the right value resistor on hand yet, but otherwise it's running like a champ! The B+ comes up nice and smooth, and the output looks smooth, like buddah!
More details to come, but I'm off to bed now. Been up for 21 hours now, and I have to get up again at 4:15 to go back to work.
Damn work interfering with my projects.
Finally am making some headway on my custom Ear+HD. More details on the overall project to follow later, but this is the PSU portion of this trip. I disconnected the B+ in my existing amp and lashed this PSU to it; and borrowed the filament power from the amp for the PSU's rectifier heat.
I've been running a bunch of sims for a while, and finally breadboarded (plywood-ed?) it this weekend with a solid state bridge. It worked very well, so I continued on tonight by replacing half the bridge with a tube rectifier as per my end plan, and fired it up (no pun intended).
Make sure the kiddies are asleep before you try this at home...
Detail shot of rare multi-ply fir circuitboard:
The original Ear+HD uses four FREDs and a C-R-C-R-C filter in the PSU. This dicey looking rig is a hybrid bridge made from two FREDs, the tube rectifier (+ out) and is now C-R-C-L-C-R-C. The LC filter was a later thought, after scrounging up a nice NOS Thordarson choke that was suitable. The voltage needs to be adjusted about 14 volts higher... I don't have the right value resistor on hand yet, but otherwise it's running like a champ! The B+ comes up nice and smooth, and the output looks smooth, like buddah!
More details to come, but I'm off to bed now. Been up for 21 hours now, and I have to get up again at 4:15 to go back to work.