Hello,
This is a companion thread to one I started earlier this year about an outboard power supply project for my WTA. I finally got around to get some pictures of the unit, inside and out.
Front Panel, the meter is my power indicator. "This little chromium switch here" directs power to the DC out or binding posts. Middle position is no connection.
Meter detail. I was lucky and found NOS Simpson meter for about $15. They go for about $90 new from the usual distributors.
Voltage running a little high. Easy to adjust and may as well since I am opening it up for these pix.
Side and back view. The holes are the original factory ones. i needed a little extra room inside so I drilled a couple more for a flush back panel. AC switch, fuse and strain relief/ AC captive power cord in.
Internal layout. I used a SOLA regulated linear power supply with 12VDC out. There are versions supporting several voltages as well, like 5 VDC.
Meter and switch connection detail. Cutting the 2 1/4 inch hole for the meter was the biggest challenge without a die punch. I drilled lots of little holes around the circumference and then used side cutters to remove the blank. One needs to be careful to not make too large an opening and remove material needed for the mounting screws. The small circuit board to the right with the silver drum potentiometer is the over voltage protection module. That is not its factory suggested position, but putting it here makes its adjustment much easier - I don't have to remove the back panel to get to it. If you look closely at the circuit board below you will see blue plastic pots. The back one allows fine tuning of the 12VDC out. Range is roughly 11 - 14 VDC.
This revision of the Sola power supply has screw connections for AC in and DC out
And the final voltage after adjustment.
So, was it worth it? Absolutely! The nasty hash from the original wall wort is gone, and it is also quieter that the PC monitor PS I used while this one was in progress. I was able to get rid of the auxillary ground wire as well (the one connecting power supply negative to the ground on the turntable that also grounds to one's phono preamp. I haven't tallied up the receipts but my guess is around $120 or so. I got lucky on some prices for key parts, my SOLA unit was $25 landed cost, most are going 2-3 times that much. And the Simpson meter was a nice find.
If you like this kind of exercise, sourcing parts in not too big a hurry and enjoy figuring out the casework and like the smell of rosin flux in the morning, check it out. Otherwise, the DSP $425 price tag is "in line".
ge
