1971 Bronco - Grounded Power Cord Conversion

[brentm]

Gents,

I have a question on a 2 to 3 prong power cord conversion.

On the said bronco below... is the correct wiring for a grounded power cable conversion the following?

Disconnect Black and Green/Black from tab of fuse - Connect to neutral of power cord.

Then

Hot (primary) from cable to tip of fuse -> Tab of fuse to power switch --> Leave Power Transformer wire connected to other side of power switch

Green from power cord to chassis.

Just want to double check. I know most of you can do these types of conversions in your sleep.

Thanks!!!!
-Brent

[M Fowler]

The attached diagram shows how it should be wired.

Mark

[Gibsonman63]

Since you have one wire coming from your power cord and one from the transformer, you can solder them both to the same lug on the ground switch as a clean way to connect them together.

[brentm]

But there is no ground switch on this bad boy.

[brentm]

The attached diagram shows how it should be wired.

Mark

Thanks Mark!!!!!

[M Fowler]

Your welcome,

Structo posted three versions of wiring a while back and I keep those in my amp mod file on my CPU for fast reference.

Mark

[brentm]

So thinking it out a little more, I'm still a bit confused. Which of these wires are neutral from the power transformer?

With the current 2 wire configuration. Is it safe to say the Black and Green/Black wires are hot and the yellow/red with black tracer are neutral?

[M Fowler]

Disonnect the incoming black power wire from the switch and move it to the fuse holder. Disconnect the white wire and other wires from the fuse holder then connect those wires and solder, cover with heat shrink tubing.

Run another black wire from fuse holder to switch.

[brentm]

Disonnect the incoming black power wire from the switch and move it to the fuse holder. Disconnect the white wire and other wires from the fuse holder then connect those wires and solder, cover with heat shrink tubing.

Run another black wire from fuse holder to switch.

Thanks again Mike! Did the conversion today, and it wasn't too bad! I did exactly what you said. Only challenge was getting the strain relief to fit as the new cord was slightly larger in diameter. Only deviation was I moved the black/black-green over to the switch and the pair of black striped yellow and red wires over to the neutral (which were originally hanging off the power switch)... just to keep things matchy matchy.

Instead of using heat shrink, I mounted a two post solder terminal strip to the corner of the transformer to connect the neutral from the tranny to the white wire and connect the ground to the chassis. worked out nicely.

I'm a little surprised these amps aren't louder! They're pretty much bedroom amps.

Thanks again for your help!

[M Fowler]

Yeah and the Bronco is a Bass amp go figure with all that reserve power