Just picked up an Allen PT (TP40D) for my custom build, and noticed that it has a hum shield brought out to a nice, orange wire. Where is the best location to ground this? With the heater/B+ CT? At the chassis ground point? Elsewhere? I've not used a PT with a hum shield before, so I don't want to make it a humming shield.
It's just that --a hum shield, so wherever it works best- probably where the ground of the power cord meets the chassis, or in that vicinity. Or not at all, if that works best, or in series thru a capacitor to the chassis if there is just more buzz than hum . Might be best to decide when the amp is done to evaluate.
butwhatif wrote:It's just that --a hum shield, so wherever it works best- probably where the ground of the power cord meets the chassis, or in that vicinity. Or not at all, if that works best, or in series thru a capacitor to the chassis if there is just more buzz than hum . Might be best to decide when the amp is done to evaluate.
You know, that's a good point. Hadn't thought of waiting until the end and then trying out various options. Good idea...