Variac amp
 

What amp variac is recommended to power up a tube Television?
Thanks

An all-tube color set might be rated at 350 watts at 117 volts =~ 3 amps

Mine has a 2A breaker IIRC, and I've used it with everything from AA5 radios to high tube count TVs like my CT-100 and 21CT55 color sets and Dumont Manchu without issue. It may be a slow trip type breaker or less sensitive than rated...I have been able to trip it driving shorted or nearly shorted equipment.

If you can find bigger it doesn't hurt to have an oversized variac as long as it's designed for your local line voltage.

One thing that is important in my book is having metering particularly for current or wattage. If you can see power consumption at a specific voltage drop off and stabilize you can monitor cap reforming and if you can watch it climb too fast you can detect and stop powering a shorted lytic before the smoke lets out.
I tend to plug a kill-a-watt meter into the output of mine so I can monitor current, wattage, and actual voltage. Some units have built in meters. You can also add your own meters....Some folks just buy an old variac adjustable transformer out of an old factory panel and make their own setup with meters, an isolation transformer and sometimes a dim bulb current limiter (if you want a dim bulb rig act fast incandescents were banned a month ago and supply is drying up).