Utracer V6 Vacuum tube curve tracer

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 A modern era tube tester?





Yes, that´s right.

The old radios in my basement was starting to demand a bit more than just swapping tubes. I wanted to be able to measure them. I did not really want an old tube tester, since they are felt overpriced, and building something from a kit or on your own is always rewarding. 

A quick google search led me to Ronald Dekker´s excellent Utracer. The Utracer is a computer connected curve tracer, that traces the response of the device under test, on your screen.

This gives you possibility to determine plate characteristics on, for example, triode connected pentodes, and there is also a quick test function, to help run through that pile of 6V6´s.

uTracer3/uTracer3_pag0.html


I ordered his V6 kit, and it came to my doorstep a few months after ordering, due to the fact that he was doing some tests before shipping.

Why wait for V6? 

Well, since I play with transmitting tubes (807´s, 6146 etc) I wanted a bit higher voltages than his V3 (true and tested since many years) tester was capable of. The V6 can deliver 1000V on both plate and screen, and down to -100V on the control grid.


The kit came together like a breeze. Kudos to Ronalds fine work in documenting everything. Everything is accounted for. How to solder the switching mosfets, how to test each stage, and how to layout sockets etc.

The quality feel was excellent. The assembly manual was printed on heavy paper, every assembly phase has it´s own little bag with components. Needless to say, the kit came together without any issues. A linear sweep of a resistor confirmed that things worked as they should.


Boxing

You will have to house your tracer by yourself. For me, that was the longest holdup, not because I cant work with metal, but most because I was lazy. One day at Ikea, the box issue was solved. 


I bought the larger Plogfåra box, which had the perfect size for my needs. I designed a "drop in" front panel in Fusion 360, with 12 sockets for tubes that I figured I could use. Octal, 9 pin miniature, 7pin miniature, Magnoval, UX4/5/6/7, Euro 4/5 pin, Euro side contact socket etc.

Switching outputs from the tester to pins of the sockets was occupying a lot of thought. I wanted rotary switches, but without multi deck switches, with a special layout, it would be very easy to short outputs together. A safer option was banana jacks and jumper leads.


Lettering.

The front panel decal was made in inkscape, from the imported Fusion 360 drawing, and sent to a custom decal manufacturer. I got it made from a wear resistant, thick decal of very good quality.


Testing

I have not tested that many tubes yet. Did test all tubes for a friends Tram Titan 2 repair that I´m doing, and it seems to work just fine.


Should you buy one? Yes. don´t hesitate. It´s fun to build, and a good tool to find.






 




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