/diy/ - Do It Yourself

This post brought to you by the Rayovac "High Energy" 9V carbon-zinc pile.

>>1539282
>the inductor must've been saturated
You didn't even calculate your charge rate? You didn't optimize your mosfet on time for the inductance? I get this is not an engineering thread but reeeeee

>>1539399
>none of the caps have breakable lids
well shit. You'd have to check under them for downsplosions, but first, I'd check the caps closest to the CRT. If you're lucky, there could be CRT tuning resistors. Usually it's just colors and intensity, but there might be ones for the vertical and horizontal deflection. You could go as far as checking the voltages on an oscilloscope, the vertical signal would only be at 60Hz, though the horizontal would be around 15-16 KHz superimposed, if it's all one coil. Easily within the range of an oscilloscope.

If you left the CRT running for a while, a failing/failed cap would get hot.

>>1539403
Absolutely disgusting. It might just be the board got goop on it, and the capacitance of some circuit is bent, or charge is leaking. Grab a toothbrush and alcohol, scrub a dub dub.

>>1539426
For a plain fuse? Tin foil was a classic and should easily be calculable with sheet thickness and width. Cheese likely wouldn't work because after burning, the carbon is still conductive.

An interesting fuse, a thermal fuse attached to mosfets, biased with a rectifier at the max amps you want. Above the rating they would rapidly heat. Could even just use a crowbar circuit, so if the voltage above the mosfets rises above say 5V (because above 15A. For a mosfet switch, you'd want schottky diodes to prevent the body diodes from shorting out (and they'd get hot, .3-.5V @ 15A = 7.5W max dissipation).

A current-detector and triac would also work, you'd need a sample-and-hold so say if it's above the threshold, it cuts out power until the sample-and-hold is reset.