3rd of July 2021 Shin-ichi from Japan turned his uTracer6 into a beautiful instrument with a redesigned heater supply!
It takes almost four months, and now I have finished assembling my version of uTracer6 based tube tracer.
Attached tracing.jpg is its figure !
I made build-in dc filament supply ( heater is also available, of course ) to trace direct heating tubes easy. This circuit refers to the PWM1 signal of uTracer6 to generate dc voltage that tracks the value of the Vh field of the GUI. Soft start ( This is a nice feature ! ) and on/off operation are controlled in the GUI's manner. Missing PWM1 pulse during measure period doesn't affect on filament voltage. A collage from my notebook (block.jpg) shows the simplified block diagram of this supply. A tiny flowchart of square root calculation gave me an inspiration about this circuit. This simple algorithm revives from 70's, the Cambrian period of eight bit microprocessors.
Inside the cabinet with uTracer6 is shown in interior.jpg. The floating supply board is positioned under the uTracer6 board.
The mainframe of this tracer does not have tube socket. A socket of required type is set on the fixture box as fixture.jpg shows. Pin selection is done in the box. Two types of fixture unit I made. One for MT sockets and another one is for larger sockets of GT, ST, compactron etc.
I thank you and uTracer6 !
Happy tracing !!
29th of May 2021 Jonas traced the “heaviest” tube so far on the uTracer6 a huge GU-78B!
Hi Ronald and Marie-José,
I am very grateful to you for your adventure with uTracer6. 2021 May 29 The most powerful tube tested by uTracer6 is the GU-78B. The GU-78B is a Russian tetrode with a maximum anode dissipation of 2500W. The tube GU-78B requires forced air cooling, a fan is applied. Oscillations are suppressed and the tube shows a curve trace. In the attachment there are several pictures in the form of a report, for free use.
The uTracer6 kit went together nicely, and as usual the manual was superb.
I can't wait to give it an appropriate case and put it to use!
1st of May 2021 Winfried sent me a few pictures of the monster GU-81 he traced with the uTracer6!
The GU-81 is a Russian military pentode with a maximum anode dissipation of 450W. The heater alone dissipates 120W (12V @ 10A). A look at the datasheet shows that the uTracer6 can only trace a small part of the curves! Winfried traced the GU-81 both in pentode as well as triode mode.
Winfried sent me a beautiful present in the form of a 3D printed case for the uTracer6 complete with all the accessories and in our national color: orange!
7th of April 2021 Francisco finished his uTracer6 and made a YouTube movie of it!
I have enjoyed so much building the new uTracer6 this weekend, and I gladly completed it without a problem. I have compared the results with my uTracer3 and they are exactly the same.
I attach some pictures and a short video.
Happy Easter Ronald,
I finished my uTracer 6 and be back with the pictures. I already finished two tube adapters also (next will be one for GU-81 tubes probably :-).
You can see the indirect LED signals at the neck of the tube adapter socket (starboard and port accordingly with red signalling high voltage and green for power on).
I found another thing in the manual that could be corrected. At page 57 you recommend the use of a 330µH inductor wich is already included with the pcb/kit.
Dear Ronald and Marie Josè,
This morning I finished the uTracer 6, following the construction manual to the letter.
I did perform the calibration correctly, extending the calibration points to 600V, and all worked flawless.
Now I'm playing with some tubes, to familiarize myself with the instrument before closing in a proper case (external PSU yes/no... I think it will be necessary).
In any case, I want to thank you for designing and sharing this useful tool, essential to playing consciously with our beloved tubes.
All the best (from Italy)
Dear Ronald & Marie-José
Thank you for your mail.
I attach two photos with this mail, the uTracer6 PCB I constructed and tracing scene. Please use them freely.
Add to my last mail, three modifications are applied to PCB.
LA1 through LA4 RFI suppression beads are covered by insulating sleeve and they are mounted on paper phenol resin sheet.
To avoid careless touching is the reason. They are tall.
Values of parts in the grid bias trimming circuit are changed.
R45 2M7 to 390k
P40 100ohm to 500ohm
The adjustment range was slightly narrow for my PCB condition.
Probably 200 ohm trimmer and 1M ohm R45 is better. But I don't have 200 ohm trimmer in my parts box.
POWER led is changed to green one. Simply because I usually use GaP green led for power indicator.
At this time, tracing is done on a lunch tray. This style is comfortable for experiment.
Upper left unit is USB to serial converter with command display. This unit includes TX/RX isolator by means of two photo couplers, to eliminate large ground loop.
A 6J11 dual pentode compactron is the DUT.
Measured plot image is collaged on the tray.
I am very satisfied with this result. Thank you Ronald!
When I understand enough about operation of this nice device, I will start designing the enclosure for uTracer6.
Yesterday, I showed uTracer6 PCB to my wife.
She said to me, "Mr.Dekker has his own aesthetics, I can feel it. This board is beautiful".
She is a graphics designer. I wish my modifications do not spoil your board design.
The kit went together very well. The instructions were clear and easy to follow. You and Ronald have done a great job putting this together. I really appreciate your effort.
I've attached some photos of the finished product. In case you're wondering, I built the chassis before I received the circuit kit. Although I've only tested a couple of 12AX7's, I haven't seen any oscillations yet. I'm keeping the snubber handy in case it is needed.
Thanks again for all your hard work.
Hi Utracer v6 arrived today, I have assembled and calibrated, works great. I have tested RF Zero Bias Transmitting Triodes, Eimac 3-500Z Russian G811, American 811A , Cetron 572B , Svetlana 572B, and Chinese 572B up to 1 KV Anode and +120V Grid1 via screen Booster.
All measurements are equal to microtracer v3 biz only up to 400 volts and 600 mA current after modification. The next day I will test some audio tubes el 34 el 84 6l6 6p3s kt66 and some double triodes ecc 83 85 88 and Russian equivalent 6n1p 6n2p and 6p3s.
Thank you and have a nice day