Awesome tube tester/curve tracer

[stokes]

I just finished this project and I highly recommend it for anybody that wants a good tester at a fair price.The uTracer, a miniature Tube Tester / Curve Tracer. It cost around $300 USD,the seller is a fantastic guy and bends over backwards to make sure you are satisfied.What he sells you is a kit to build the main board,you have to devise your own switching and tube socket set up.I was able to keep it simple,no switches.I used a small project box with just 3 sockets hardwired to the board.I only test audio tubes for guitar amps so my need is limited,I have an octal socket for 6L6 types,a 9 pin for EL84's and a nine pin for 12AX7 types.I plan to use another box with a couple more sockets for a couple more audio tubes that will plug into my existing unit,no switches needed.If you need a wider selection of tubes to be tested you will want to make a more complicated switching matrix,but it wouldnt be too hard to do.It is kind of complicated to use at first,but once you get used to the set up procedure its fairly straight forward.

[km6xz]

That is an interesting and reasonably priced kit. It does have some limitations for testing power tubes that a traditional curve tracer does not but it also has some great features. I have two old test instrument tracers, a Tektronix 570 and the Fairchild that will generate at lot higher anode potentials but having an easy to use unit like the uTracer that stores set ups and allows screen and data capture means just about anyone serious about designing with tubes ought to get one of these. I am considering buying one because it solves a problem I had of recording family curves for each tube that I was offering on tubes I was buying from China, testing and printing their curves with individualized serial numbers.
Thanks for the heads up.

[stokes]

The limitations on the anode potentials I find to be insignificant,300v's are plenty for getting a good idea as to a tubes performance.Most common testers dont go near that.The customer support the designer/seller of this kit is probably the best I've ever experienced,I had a small problem with my build,we tried troubleshooting via email,at some point he had me send the whole build back to him to try to dignose.Turned out to be a mistake in the way I was using it.He spent a lot of time working with it before we realized my mistake.No charge at all.You will not be sorry if you purchase this unit,it is the most useful tester I've ever seen.

[km6xz]

Running curves with parameters unlike the intended circuit will indeed give misleading information. Sure, better than an emission tester but it still leaves you with a big hole in the data at the conditions of most concern of an amp designer. When sweeping anode potentials up at the peak of expected operation in the amp, it is common to see deviations from the trendlines seen at low levels. A chassis dyno that tells you a lot a 200 peak HP does not tell you much about what it performs like up at twice the rpm when expecting 800 hp in real world use. Matching sections of preamp tubes(not really an advantage one way or another) would certainly be a good use of the pulse type tests at the voltages available. Testing power tubes to be used in amps with 500-600v B+ would introduce some doubt how well the tube was characterized when tested at 300volts max. All the purpose built tube curve tracers would sweep up to 1kv or more.

[stokes]

Well,if you need a tester that goes to 600v's,then obviously this isnt for you.For my needs it is more than adequate.All my work involves tube guitar amps,mostly vintage but even the more modern circuits use well under 500v's on the plates,usually.I really dont see a need to know how a tube performs at 500v's,and if I did there is plenty of data already in print to tell me how it will,there really is nothing new or groundbreaking in tube technology,its all been done over the last 5 decades.For my use a tester must tell me a tubes "strength" via gm readings,current draw and amplification factor,or mu at specific parameters set by the engineers that designed the tube and can be found in many manuals,if a tube meets these parameters it is a well functioning tube,either at 300v's or 400v's.

[Old Tele man]

FWIW, our slogan amongst defense engineers is "...test it like you fly/use it..."

[Ted]

We say "Test what you fly. Fly what you test"

[mhuss]

I've had a uTracer for a while now, and it is a great little device. I've gotten it up near 400v with some careful tweaking. Higher anode voltage is a frequent request from users. ;-)

[nickb]

I've had a uTracer for a while now, and it is a great little device. I've gotten it up near 400v with some careful tweaking. Higher anode voltage is a frequent request from users. ;-)

I built one too when Ronald first did the kit. I used thumbwheel switches to configure - it was very easy to do.

I didn't especially like the GUI so I wrote a new one that added direct SPICE model generation. I have to say I really should update it to take advantage of the fine work that Derk Reefman did on better SPICE models. Mine were based on Koren's with the addition of a new screen current model but I was never happy with my model for beam-tetrodes. Derk's models would fix that.

Here's mine. I just waned the test the most common tubes so I didn't go crazy with types of sockets. I left room for more though...