4-4-0 [2 NEW BUILDS WITH PICS; THE 2 WATT WRECK]

[tristanc]

This is my bias circuit. The two key resistors are circled in red. R49 drops the high voltage down and sets the 'upper' level of your bias range. R54 sets the 'lower' level of the range.

You can ignore the other parts (diodes and 100k resistors here and there) as these are improvements suggested by Merlin and stick to the stock 4-4-0 schematic. But the values of the dropping and tail resistor are key to getting a usable bias range.

Full schematic here: https://www.tristancollins.me/ax84/Muti ... dio_v1.pdf

[pompeiisneaks]

This is my bias circuit. The two key resistors are circled in red. R49 drops the high voltage down and sets the 'upper' level of your bias range. R54 sets the 'lower' level of the range.

You can ignore the other parts (diodes and 100k resistors here and there) as these are improvements suggested by Merlin and stick to the stock 4-4-0 schematic. But the values of the dropping and tail resistor are key to getting a usable bias range.

Full schematic here: https://www.tristancollins.me/ax84/Muti ... dio_v1.pdf

Thanks Tristanc! I was trying to remember how that worked and you just explained it precisely, hopefully I'll remember this from now on too

~Phil