[Swan] tube tester

[Kenneth G. Gordon]

On 19 May 2007 at 21:32, w7lrd at comcast.net wrote:

> Greetings
> I have about 30+ 6LQ6 and similar tubes.  They are all used (by me
> over the years).  I want to test them in one of my 350C or 500c.  Can
> I run each one "one at a time" and see what it loads up to and record
> the results and perhaps match these tubes up.  Has anyone tried this? 
> For if I run two tubes at once the total Ip is just that the total,
> and one tube may be working like heck and the other hardly working. 
> Any advice/sugestions.

What you suggest above sounds OK to me, although with only one tube 
in place the neutralization will not be correct.

However, more than likely, that won't be a problem on 80 meters. I 
would hesitate to do the testing at 10 meters, though, without correctly 
adjusting the neutralization with only one tube in place.

If I were going to do as you plan, I would first do a complete and 
accurate neutralization procedure with only one tube in place, then run 
my tests up through 10 meters.

Also, I would use the same socket for everything. Minimize the other 
variables. I prefer dealing with one variable at a time.

I think it might be a good idea to measure the screen current of each 
individual tube also, since that would give you a good indication of 
possible gassiness or screen emission.

Ken Gordon W7EKB