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Hello,
Removing the shield on the pentagrid converter was definitely a good idea to
enhance oscillator radiation. You now have to see why it's not oscillating.
Check the continuity of the IF transformer primary (1st IF transformer) that
feeds the plate of the 6BE6. Then, under power, measure the plate and
gride voltages on the tube and compare with schematic. Testing with the new
tube might also be a good idea. There is also the possibiliy that the coil was
not installed correctly after you rewound it. Oscillation depends on feedback
from grid (pin 1) to cathode through the circuit formed by C4, coil and C2+C2A.
Also, as I told you before, the oscillator is more likely to work at a lower frequency
if something is marginal in the circuit, so just leave the tuning at the low end
of the band while searching for oscillations with the test receiver. You may also
want to disconnect the coil from the variable capacitor and make sure the
capacitor itself is not shorted (bent plate). You have to disconnect the coil
to do this, otherwise you would be just checking the continuity of the coil.
The article on 'pentagrid converter' in wikipedia might make good reading if
you haven't already looked up. Bye for now.
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