67 Deluxe Reverb Bias ports, Moment of Clarity

[dwp]

     Hey check this out and why didn't I think of this before? Especially since I just determined that my MA type in line bias checker doesn't read well anymore, was 10MA off, said 25 was really 35.
     I drilled the centers of the blade slots on the factory mounted 120V receptacle, just large enough to accept my multi-tester leads, then wired the 1 ohm resistors to them. Doug your 1W-1 Ohm-1% resistors are scarey small, not going to explode in there, right? would be a very small explosion....(lol)

Everyone else already do this? doesn't look defaced at all. Use at will.

Thanks, dwp

[HotBluePlates]

Doug your 1W-1 Ohm-1% resistors are scarey small, not going to explode in there, right?

Ohm's Law.

Let's say your tubes started passing 100mA (0.1A) each.
100mA * 1 ohm = 0.1v
0.1v * 0.1A = 0.01w

So a 1w resistor has a 99x safety margin. 1w is probably used because a smaller wattage would be physically smaller as well.

[dwp]

yes I get that but have you seen the size of these resistors? smaller than the picture. you'll fear bending the leads in that the resistor body may break in half.....
(more feeble humor)
thanks hpb. watcha think on the receptacle usage? cool? stupid? old hat? Was all proud of myself, no need for chassis holes in my vintage road warrior.

[LooseChange]

Yeah those 1 ohm 1% resistors are small... The size of a 1/4 watt carbon film from radio shack.
It's a good idea.

[HotBluePlates]

I hear ya. I think the small size is all about the implied voltage rating. But I hear what you're saying; I've used them before and they're tiny.

If a larger resistor would make you feel more confident, use it. It probably won't perform as well as the tiny precision resistor, though.

Actually, I think this is a really great idea. I wish I'd thought of it!