[Solved] Problem connecting wires to heater of ECL86 tube

Schematic
1

Hello,

I (absolute beginner) am trying to draw a schematic for a tube amplifier using the ECL86 from the built-in components library. Unfortunately, I cannot connect the wires of the heater pins. Connecting wires to other pins (and components) works without problems. I tried an ECC83 as an alternative and could connect the heater wires, too. (The ECL82, which has the same footprint as the ECL86 will not connect the heater, either.)

I would post an example to reproduce the problem, but as a new user I cannot upload attachments. Nevertheless, I would appreciate any suggestions.

I use Version 6.0.6 on Debian installed from the bullseye backports.

Best regards,

Bernbacher

2

You can now attach. Welcome aboard.

3

Great, thanks a lot!!!

4

Have a look at the symbol to see if the heater pins are in a different unit, similar to how ICs have a power unit.

5

Thanks a lot, I will give it a look. I will also upload the example project.

Bernbacher.

6

A, B and C. good call.

7

Here is the example with the ECC83 and the ECL86. The wiring in the example does not make any sense, of course. But it should help to reproduce the problem. (Connecting wires to the heater of the ECC83 is straightforward, but they do not snap to the heater pins of the ECL86.)

test_ecc83_ecl86.zip (12.7 KB)

8

I am too lazy to open the .zip, but I wonder if there is a problem with the vacuum tube pins being off grid? Makes sure that you use a grid of 50 mils when placing and wiring all symbols. A 100 mil grid might not work when wiring, and finer grids are only for moving text etc.

9

I’m so ancient I even remember the id scheme:

E 6.3V heater
C triode
L power pentode
8 noval glass base
6 unique digit

:man_facepalming::scream_cat:

10

I have just had a look at the heater of the ECL86 in the “Edit symbol”, Symbol checker, and it says:

Off grid pin 4 ‘F1’ at location (-2.54 mm, 9.53 mm) in unit C.
Off grid pin 5 ‘F2’ at location (2.54 mm, 9.53 mm) in unit C.

Currently, I do not know how to interpret this. But I will try to find out.

I also reduced the grid resolution down to 0.01 mil, but it did not help.

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(Replying to retiredfeline) Yes, the ECL86 is difficult to get these days. I am refubishing an amplifier I built about 30 years ago, and the PCB I made for this stage is not good. So I am trying to make a new one from scratch…

12

I could move the pins in the symbol editor, save the ECL86 in a new library and import it into my schematic. Now it seems to work. I will try again tomorrow. If moving the pins solves the problem, I should file a bug report, shouldn’t I?

Good night and thanks all of you for your quick help.

Bernbacher

13

I gave in to the temptation and downloaded and opened the file. I could wire to all pins of the ECL86 with no problem. Maybe the glass envelope of your sample is warped. :slight_smile:

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If you’re using a standard grid and the symbol is misaligned then yes it’s a bug. Probably nobody’s used it in ages.

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Its a bug in the symbol. No symbol pins should be off the 50 mil grid and there is no “shortage of space” excuse on this one. @Bernbacher is likely the first person to ever use this one since it got added to the library

16

That should be interesting. Do post screenshots in Projects when you have finished, if only because it’ll be a refreshing change from microcontroller of the month projects. :smiley_cat:

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Thanks a lot for all your help. I moved the heater pins, so I can go on with my schematic, and created a bug report https://gitlab.com/kicad/libraries/kicad-symbols/-/issues/3187.

The design is not mine, but when I am done I will check with the developer if I can publish it or if there are any copyright issues.

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