Bell & Howell Filmosound 179

[jujudubluz]

Ha !
Will work on my own !
Thanks !

[jujudubluz]

hi and happy new year ...

here we are - came up with this mock up :

single channel 5E3 à la 5E5 with a switch to parallel 15ay7

i really want to keep up with the chassis as it is : single input / single volume / single tone ...

do you see any mistake ?

cheers

ju

https://drive.google.com/file/d/1pLYKMU ... sp=sharing

[B Ingram]

... came up with this mock up :

... a switch to parallel 15ay7 ...
do you see any mistake ?

You don't want to leave the grid floating when you disconnect drive to one side of the input tube.

Use a Single-Pole Double-Throw (SPDT) switch:

• Grid goes to the Center lug

• One Outer lug goes to Pin 2 as you have drawn

• The other Outer lug goes to a resistor (any value from 47kΩ to 1MΩ) that runs to Ground

Resistance value doesn't matter a lot, but lower-resistance offers less risk of inducing noise.

[jujudubluz]

Hey !
Thank you a lot - I will update my schematic and keep you posted !
Thank you again

[jujudubluz]

here is the updated schematic :

https://drive.google.com/file/d/1hUJZMl ... drive_link

thank you

[B Ingram]

here is the updated schematic :

https://drive.google.com/file/d/1hUJZMl ... drive_link

Try it like the image below. This version implies Pin 7 of the Input Tube is connected to the switch's center lug.

[jujudubluz]

Thank you !

My mistake - get it ! Pin 7 is either connected to pin 2 or to ground.

Will update my schematic.

Thank you again

[jujudubluz]

Here is the modified schematic.
Thank you

https://drive.google.com/file/d/1G3kUir ... sp=sharing