Testing 6111 tubes

[madbean]

A couple of people have asked if there's any way to test their 6111 tubes before building the UberTuber. The answer is yes, and it is very simple. Just put the following circuit on a breadboard to test one of the triodes. If one triode biases and works properly both should. But, you can test both sides if you want to be certain - just use jumpers to move the connection points on the resistors and caps between the two sets of plates, grids and cathodes.

- I'd also advise against buying unlabeled 6111. If a seller doesn't list or show the manufacturer don't bother. There are still lots of Raytheon 6111 out there.

- This is a barebones circuit which will give you some output. It will sound a little bassy as is but remember this is just a test. The whole thing should take 10 minutes at most.

- BTW - these tubes are EXTREMELY durable. I've soldered and desoldered the same tube many times. The leads don't break with normal care and you'd have to really try to burn one of these tubes up just through soldering.

- If any of you have run into trouble and think you need to replace the tube on your build I have some spare daughter boards for the UberTuber. Just PM me.

[madbean]

BTW: another way you can try testing the 6111 tube before soldering:

Solder in the 8 pin right angle header to the main board. Install the tube into the daughter board but don't solder it or cut the leads (but you can fold the leads over the pads a bit)! Then slide the daughter board over the header. Again, don't solder! The weight of the tube should push the leads, pads and header into contact just enough for a quick check. It should be enough to test voltages and for output.

Just thought of this!