Compu bias displays PV / Ma & Wattage output in pairs real time. Great gadget cept the guy stopped selling them right after i got it.
Ive not had a problem. I'll run it into the ground and when it dies be "happy to pay my tech to take the Zap for me".
You have to poke around the underside of Hot tube sockets with live 480vdc.
My eyesight be going thru changes.
I have to wear a headlamp & glasses just to solder pots and shit now.