With the 4th of July behind us, I should share as a kid that I also found the 4th to be a somewhat sad milestone. Summer vacation from the rigors of attending school was headed on the downward side. In no time it would be time to shop for flannel shirts, heavy socks and winter coats. Gone would be fresh corn on the cob and watermelon. It also meant soon no enjoying sitting on the back porch and watching the fireflies. We are headed on the path to winter. The longest day of the year (for sunlight) has passed too! Project X Home Power Supply I managed to acquire the schematic for the Project X home power supply and some information in that design is noteworthy. A Tribal Knowledge Trick is to use a center tapped secondary winding on the power transformer where the that winding feeds a bridge rectifier and the center tap provides about 1/2 the voltage. In our case if the secondary was 500 volts (250 Volts either side of CT) then the bridge output would be 700 VDC +. Here two VR tubes ...
The project cluttering my workbench (Project X) has many challenges ranging from actually getting it to work to how do you power the beast. Tempo One FP-200 Weird and Strange are two really good words. As advertised Project X can be powered from a home (AC) supply or mobile from the DC Supply. In either case the HV is 750VDC, the LV is 210VDC, the Bias is -60VDC, the Filaments are 3.2 Volts at 3.2 Amps and 12VDC at 1.5 Amps. So, at the N6QW Radio Ranch, I have a Heathkit HP-23, Drake AC-4, Drake DC 3, Collins 516F2, Collins PM2, National NCXA and a Tempo One FP-200. While all of these supplies cover some of the requirements of Project X, none is a drop in. In looking at the herd, one supply is left over from a project called Resurrection Radio where I took a Tempo One (worse shape than Project X) and brought it back to life. I bought a FP-200 to power that radio and when I sold The Tempo One, I kept the FP-200 JIC that someday it is needed. Well, some day is here. Resurrecti...