OK, now we know something about the radio. The first thing to do is interchange the two 6SK7s and see if the test on V3 changes. Also it would be good to check a few voltages. If you look at the schematic, you will see what looks like an inverted T at the top of each tube. This is called the plate and that is where the highest voltage in the tube usually appears. So it would be a measurment between chassis and these points as follows:
V1 pin8, V2 pin3, V3 pin 8, V4 pin 6 and V5 pin 3. Your meter would be set to DC volts with a range of 300 volts or greater.
I should emphasize that you don't want to come in contact with these voltages!