10-01-2017, 02:39 PM
That's probably good way to judge the 37-630 middle of the road. It does have a few of the features of the bigger sets like a rf amplifier and shadow meter but falls short on several areas. Single ended audio output nicer sets will have a push/pull output stage. These will develop higher output levels with low distortion. A single 6F6/42 will make about 3.5w in p/p about 10w sez RCA.
Pentigrid mixer, nicer sets will use two separate tubes a mixer tube and an oscillator tube. Using two tubes allows the mixer circuit depending on the tubes that are used more gain and operate more quietly. Can also operate without oscillator pulling at higher frequencies. See the diagrams for the 116X, 37- 675, 116, and 690.
Single IF amplifier. Better sensitivity and selectivity can be had use two IF stages.
With saying all that is it a horrible set?? No not at all. It is a fairly simple set to service from an electronic standpoint but the rf subchassis does add a bit of difficulty.
Pentigrid mixer, nicer sets will use two separate tubes a mixer tube and an oscillator tube. Using two tubes allows the mixer circuit depending on the tubes that are used more gain and operate more quietly. Can also operate without oscillator pulling at higher frequencies. See the diagrams for the 116X, 37- 675, 116, and 690.
Single IF amplifier. Better sensitivity and selectivity can be had use two IF stages.
With saying all that is it a horrible set?? No not at all. It is a fairly simple set to service from an electronic standpoint but the rf subchassis does add a bit of difficulty.
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
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