08-13-2016, 11:49 AM
Well there are two ways. One is to whip out your handy dandy 1940 tube manual and look it up. Nowdays I look it it up online. Some schematics have the pin numbers indicated on them some not.
I think you maybe be asking how do I count pins on the bottom of a tube?
Older standard base tubes: 4, 6, and 7 pin tube are simple. Find the two fat pins looking from the bottom. Face them towards you. The pin on the left is pin#1 count clockwise to determine the others. For instants a 4 pin tube pin 1 is the fat pin to the left. Pin 2 is the thin one above it. Pin 3 is the thin pin to the right of pin 2. And pin 4 is the other fat one.
On the 5 pin tube two of the pins are closer together. Pin 1 is the one on the left of two that are closer together, pin 5 is the one to the right of pin1.
Schematics that don't pin numbers doesn't mean that the connections are layed out in the order in which they appear on the schematic.
I see I'm late to the party! Slow typer.
I think you maybe be asking how do I count pins on the bottom of a tube?
Older standard base tubes: 4, 6, and 7 pin tube are simple. Find the two fat pins looking from the bottom. Face them towards you. The pin on the left is pin#1 count clockwise to determine the others. For instants a 4 pin tube pin 1 is the fat pin to the left. Pin 2 is the thin one above it. Pin 3 is the thin pin to the right of pin 2. And pin 4 is the other fat one.
On the 5 pin tube two of the pins are closer together. Pin 1 is the one on the left of two that are closer together, pin 5 is the one to the right of pin1.
Schematics that don't pin numbers doesn't mean that the connections are layed out in the order in which they appear on the schematic.
I see I'm late to the party! Slow typer.
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
