Head-Fi.org › Forums › Misc.-Category Forums › DIY (Do-It-Yourself) Discussions › Idenitifying tubes, testing tubes
New Posts  All Forums:Forum Nav:

Idenitifying tubes, testing tubes - Page 2

post #16 of 24
12/11/09 at 5:23pm
I've noticed that there's a decided air of exclusive superiority that goes with some tube tester owners - mine's better than yours, that sort of thing - just seems to go with the territory. I've found it's mostly unfounded, though.

Talk to Radio Electric Supply, Tube Depot, etc. - any of those guys. They test and match at reduced voltages all the time. Heck, I spoke to the retired EE professor that Roy and Dale employ for almost an hour one day. Their $10,000 (can't remember, but it was somewhere in that range) fully-computerized tube tester tests at a greatly reduced voltage - only 4 or 5 volts on Millett tubes, for instance.

Being in the business it would seem that if that were to cause them trouble, they'd change (me, too). Regardless, I bet theirs is more expensive than yours, Les.
Reply
post #17 of 24
12/11/09 at 7:27pm
Quote:
Originally Posted by n_maher View Post
Just about any tester you can buy (provided you are intelligent enough to buy one that tests the tubes that you want to test) can test for shorts. You call that useless?
As a "Tube Tester", yeah useless. I can do that with a DMM and a set of Alligator clips I'm thinkin'. A "Tube Tester" does a lot more than short testing.
Reply
post #18 of 24
12/11/09 at 7:35pm
Quote:
Originally Posted by tomb View Post
I've noticed that there's a decided air of exclusive superiority that goes with some tube tester owners - mine's better than yours, that sort of thing - just seems to go with the territory. I've found it's mostly unfounded, though.

Talk to Radio Electric Supply, Tube Depot, etc. - any of those guys. They test and match at reduced voltages all the time. Heck, I spoke to the retired EE professor that Roy and Dale employ for almost an hour one day. Their $10,000 (can't remember, but it was somewhere in that range) fully-computerized tube tester tests at a greatly reduced voltage - only 4 or 5 volts on Millett tubes, for instance.

Being in the business it would seem that if that were to cause them trouble, they'd change (me, too). Regardless, I bet theirs is more expensive than yours, Les.
They usually test with what they have or can afford to have. If they have a "Good" tester they will specify what they tested with, and the reason they specify it is because they want to lend credibility to the test. Saying a Tube is "Good" means not much. It was said earlier in the thread that the "only" real way to "test" a tube is to put it in the amp. That's true. Because it is being tested at real world Voltages and workload. I have by no stretch what I would like to have as a tube tester, so you're right, theirs is most likely nicer than mine. Mine is just enough to get me along.
Reply
post #19 of 24
12/11/09 at 7:46pm
BTW, Nate's (I have one, too) Jackson 648S is one of the better tube testers on the market. They used a method of testing dynamic conductance that's supposedly a lot better than a simple emissions tester. The 648S is so popular that Jim Cross (Chairman of the Tube Collector's Association) re-wrote the manual and sells it at vacccumtubesinc.com.

Although I switched to the 658, either one comes in very handy in a production environment. I typically test/match ~50 at a time and would be lost with the involved setup on a Hickok.

As you referenced, a lot of this info can be found at the Tone Lizard, too -
Tales From The Tone Lounge; Jackson Tube Testers
Reply
post #20 of 24
12/11/09 at 10:24pm
Quote:
Originally Posted by tomb View Post
BTW, Nate's (I have one, too) Jackson 648S is one of the better tube testers on the market. They used a method of testing dynamic conductance that's supposedly a lot better than a simple emissions tester. The 648S is so popular that Jim Cross (Chairman of the Tube Collector's Association) re-wrote the manual and sells it at vacccumtubesinc.com.

Although I switched to the 658, either one comes in very handy in a production environment. I typically test/match ~50 at a time and would be lost with the involved setup on a Hickok.

As you referenced, a lot of this info can be found at the Tone Lizard, too -
Tales From The Tone Lounge; Jackson Tube Testers
Very familiar with it...
Reply
post #21 of 24
12/12/09 at 3:24am
For a causal tube user a good set up is an adjustable CCS fed grounded cathode circuit. Using brand new tubes as standards you can compare tubes by measuring the voltage at the plate. It works better than 90% of the tube testers out there.
Reply
post #22 of 24
12/18/09 at 3:16am
Thread Starter 
Quote:
Originally Posted by keyid View Post
1. my plates are narrow ribs like this picture, not flat wide
http://cgi.ebay.com/ws/eBayISAPI.dll...m=110465709367

2. The four holder tips on top and bottom are half a Octagon like a house.

3. The opening on the each flats which is punched are closer to the center

Im sure GE or their plants they made more than one type of 6680, maybe yours is older as the box looks vintage.
I was never really able to open that image (a week ago to now), it just sits there loading, do you have another one?

also, I am new to tubes and the terminology and am not sure what the holder tips, flats opening, etc.

I have yet to install them as I need to figure out what I need to re-do on this SOHA II I bought.
Reply
post #23 of 24
12/21/09 at 8:55pm
Thread Starter 
Any other comments on confirming/denying that this is a 6680?
Reply
post #24 of 24
12/29/09 at 4:40am
Thread Starter 
So I finally got around to trying these out in my SOHA II - I get a 19V drop on one, but only 15V on the other. Should I be cautious or just try them out? What are the implications on sound?
Reply
New Posts  All Forums:Forum Nav:
  Return Home
Head-Fi.org › Forums › Misc.-Category Forums › DIY (Do-It-Yourself) Discussions › Idenitifying tubes, testing tubes