Has Anyone Here Thought Of The Possible Fire Potential Of Tube Amplifiers?

[sKiZo]

Indicator that someone somewhere didn't read the part about not rocking the tubes in the sockets, right?

PS ... even tubes with a good key can be inserted incorrectly with enough force. Don't ask me how I know. <G>

Always good to closely check alignment visually.

 

[Pio1980]

Only Loktals were recommended to be rocked to be removed, and was still rather risky for cracking the glass around the pins. I still have a Loktal puller in my tool box, somewhere.

 

[s-petersen]

When I was in my early twenties, I repaired an Atwater Kent floor standing radio, I had the chassis out on my workbench(in my bedroom)
playing, and fell asleep. I woke up to a room full of smoke, it scared the heck out of me. The chassis had no fuse, if I remember.The power transformer overheated,it was still playing,and sounded fine,but the transformer had some shorted turns,and had to be replaced

 

[Tubologic]

Indicator that someone somewhere didn't read the part about not rocking the tubes in the sockets, right?

PS ... even tubes with a good key can be inserted incorrectly with enough force. Don't ask me how I know. <G>

Always good to closely check alignment visually.

This can happen, and you don't even need a broken key: I once ruined a brand new 300B by inserting it the wrong way, the crappy chinese UX4 socket has too big pin holes allowing the tube to be inserted any way. The tube heater really didn't liked receiving full B+, glowed brightly but shortly then died. Allways check good tube positioning before inserting it and powering up the amp.

 

[gadget73]

non-keyed tubes are definitely a bit scary to plug in. I've got a number of them in old radios, and sometimes when you're dealing with a tube socket that has seen multiple tube replacements since the 1920s, they're not exactly precision fit anymore.

 

[Freo-1]

non-keyed tubes are definitely a bit scary to plug in. I've got a number of them in old radios, and sometimes when you're dealing with a tube socket that has seen multiple tube replacements since the 1920s, they're not exactly precision fit anymore.

The 1625 tubes are not keyed either. Luckily, the two filament pins are larger, but easily finding the larger pins on the tube sockets is not always easy. Some of the JAN 1625's have a little bump on the side of the Bakelite where the filament pins are.

 

[gadget73]

yeah, the fat pins locate it. Not so bad in molded bakelite, but on some of my really old tube sets, the sockets are basically just holes drilled in what I presume to be bakelite sheet with spring brass contacts below it. Those holes wear after a while, and if they get too bad the fat pins will go in anywhere. Generally you don't hurt any of the 4 pin radio tubes if you get them backwards, but the rectifiers don't like it. If you get it rotated so it connects B+ to the heater string, it also doesn't like that very much.