10-04-2014, 12:07 PM
Connecting a counter to the grid of the oscillator is a definite NO NO!!! What ever you use to make that connection will as capacitance and lower the frequency; as soon as you remove the connection the frequency will go up.
You need to wind perhaps 10 turns of and small insulated wire to make a loop of about one inch; that will be your counter pick-up. Just put the loop around the tube (without shield) or put the loop in the general area of the oscillator coil. Remember that the oscillator should be 455KC above the dial freq.
With your radical freq error between 600 and 800KC, that's not from an error in coil turns- no way. Look very carefully at the tuning capacitor plates; they should be perfectly centered. It sound like you have a near short in the tuning cap, most likely one of the outer plates.
You need to wind perhaps 10 turns of and small insulated wire to make a loop of about one inch; that will be your counter pick-up. Just put the loop around the tube (without shield) or put the loop in the general area of the oscillator coil. Remember that the oscillator should be 455KC above the dial freq.
With your radical freq error between 600 and 800KC, that's not from an error in coil turns- no way. Look very carefully at the tuning capacitor plates; they should be perfectly centered. It sound like you have a near short in the tuning cap, most likely one of the outer plates.
Pete AI2V