[Nisbeth]

I'm trying to lay out PCB's for a few small tube circuits using 6922/6DJ8 tubes, but how in the #&€%! do I connect the heaters to the (proper) tubes? I sorta figured out that I have to connect each heater separately but I can't get it to link the heater and the tube. Does anybody know how to do this?


/U.

 

[tangent]

I'm not sure what you mean, since I'm vague on tube concepts. But, here's some wild guesses:

- Does this "heater" have a representation on the schematic? I.e., is there a pin on the tube symbol for it, and is there a net running from that to whatever you want it to connect to?

- Perhaps you need to look into net names and net classes. These let you force things to connect together that aren't part of the schematic, such as ground connections to the ground plane.

 

[Nisbeth]

Quote:

Originally Posted by tangent I'm not sure what you mean, since I'm vague on tube concepts. But, here's some wild guesses: - Does this "heater" have a representation on the schematic? I.e., is there a pin on the tube symbol for it, and is there a net running from that to whatever you want it to connect to?

Yes and no. A 6922-tube consists of triode1, triode2 and a heater. If I choose the 6922-part from the library Eagle will place triode 1 and triode2 in the schematic (just like the two parts of a stereo pot) but not the heater. There's a separate heater symbol in the library but if I place that in the schematic it isn't connected to the corrresponding pins on the tube when I switch to the board editor. This means that even if I connect a power source to the heater on the schematic, it isn't actually connected to the tube pins on the board

Quote:

Originally Posted by tangent - Perhaps you need to look into net names and net classes. These let you force things to connect together that aren't part of the schematic, such as ground connections to the ground plane.

I'll check the help files and manual again

Anyone else?


/U.

 

[tangent]

Ah. Sounds like the library part isn't built very well, then.

Faced with this, I think I'd edit the library and attach the heater pin to triode1, in the same way that a dual op-amp part would have the V+ and V- pins attached to the channel 1 symbol.

 

[Nisbeth]

Thanks for the help

. I opened the part in the library editor and disovered that the heater wasn't placed automatically. Once I'd fixed that it worked

/U.