I added a 600 ohm resistor in front of the choke as I realized that the DCR of the original field coil was much higher than that of my choke. This brought things much closer to the desired voltages. I was able to get AM working last night and did some DXing. From here in north central Indiana I was getting NYC and Nashville.
This afternoon I was able to get dozens of stations including several from Chicago and one from Cincinnati. Best AM performance in the house already without any attention to alignment.
At 118V in I am getting 308 on the plates of the 6V6s v.s. the desired 270 but the heaters are right at 6.3V
Noting that the original OPT also had several hundred ohms more DCR I plan on adding another 250 ohms to the input to the choke which should get me down around 285V which should be fine.
mike
10-25-2009, 02:40 PM
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