01-09-2017, 01:35 PM
Hi Mike and welcome,
For starters the radio chassis needs to be in tip top shape. This means all new paper and electrolytic caps, all resistor within 20% tolerance and a good set of tubes. Align the rf and IF stages. With a chassis w/poor sensitivity it's a waste of time and is very frustrating to try to get the sm to work properly. A good indication is if you receive a strong signal (from a generator or on air) you should be able to develop about -10v on the avc line.
Use the adjustment screw to set the vane straight. Should be able move the vane by gently blowing on it. If not it's probably centered in it's pivots. Align lamp filament for best shadow.
Generally I find that the sm isn't very sensitive. Doesn't react to weak signals very well. I live in an area where there is a lot of strong signals and a lot of noise.
For starters the radio chassis needs to be in tip top shape. This means all new paper and electrolytic caps, all resistor within 20% tolerance and a good set of tubes. Align the rf and IF stages. With a chassis w/poor sensitivity it's a waste of time and is very frustrating to try to get the sm to work properly. A good indication is if you receive a strong signal (from a generator or on air) you should be able to develop about -10v on the avc line.
Use the adjustment screw to set the vane straight. Should be able move the vane by gently blowing on it. If not it's probably centered in it's pivots. Align lamp filament for best shadow.
Generally I find that the sm isn't very sensitive. Doesn't react to weak signals very well. I live in an area where there is a lot of strong signals and a lot of noise.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry