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Hoffman Amps Forum image Author Topic: National Dobro 400  (Read 2481 times)

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Offline isaac_teller

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National Dobro 400
« on: September 18, 2023, 11:06:05 am »
Hello. Just noticed something on this schematic. There should be a grid leak resistor on the grid of V4a. What would its value be?
https://el34world.com/charts/Schematics/files/Valco/National_Dobro_400.jpg


Offline sluckey

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Re: National Dobro 400
« Reply #1 on: September 18, 2023, 01:19:03 pm »
100K.
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline isaac_teller

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Re: National Dobro 400
« Reply #2 on: September 18, 2023, 03:13:37 pm »
Thanx.

Offline kagliostro

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Re: National Dobro 400
« Reply #3 on: September 18, 2023, 03:38:47 pm »
Better ?



Franco
« Last Edit: September 18, 2023, 03:41:45 pm by kagliostro »
The world is a nice place if there is health and there are friends

Offline isaac_teller

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Re: National Dobro 400
« Reply #4 on: September 19, 2023, 10:47:42 am »
Perfect!

 


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