Talk about something useful

http://www.trioda.com/tools/triode.html

!!!!!

I tried it with the ECC83 to try to get the operating point I use in the EZTube mixer. It won't let be set the HT voltage lower than about 267 volts.  Am I doing something wrong?

Cheers

Ian

I've got the same problem with ECC88 and ECC99, didn't really try others. HT voltage is unusually high for typical mic amps, something seems strange here or it was meant mostly for power tubes.

My3gger said:

I've got the same problem with ECC88 and ECC99, didn't really try others. HT voltage is unusually high for typical mic amps, something seems strange here or it was meant mostly for power tubes.

Click to expand...

Yes, it seems to be a 'feature'. Pity really because it would make a very handy tool for setting operating points.

Cheers

Ian

You have the operation point at the top, were you set the particular point of the load line, and a range for it to estimate THD and output power, signal level, etc.

If some of those lines takes you curve out of the graphic it stops, you have to move the arrows on the top, I couldn't get anything under 30V since it's so squashed down that it can't be read, but it get's there with no problem.

JS

ruffrecords said:

I tried it with the ECC83 to try to get the operating point I use in the EZTube mixer. It won't let be set the HT voltage lower than about 267 volts.  Am I doing something wrong?

Cheers

Ian

Click to expand...

I don't notice that. I can go as low as 37V. You have to decrease Iamax to makethe graph readable.

My3gger said:

I've got the same problem with ECC88 and ECC99, didn't really try others.

Click to expand...

I can go down to 37V and 44V respectively. 

HT voltage is unusually high for typical mic amps, something seems strange here or it was meant mostly for power tubes. 

Click to expand...

Not really, since it takes only triode mode into account.

abbey road d enfer said:

ruffrecords said:

I tried it with the ECC83 to try to get the operating point I use in the EZTube mixer. It won't let be set the HT voltage lower than about 267 volts.  Am I doing something wrong?

Cheers

Ian

Click to expand...

I don't notice that. I can go as low as 37V. You have to decrease Iamax to makethe graph readable.

Click to expand...

Now that's useful, I used to go on the tube data sheets and draw lines with the PDF editor over the graph to make the first approach, this is useful now! Thanks rafa and thanks abbey.

JS

ruffrecords said:

I tried it with the ECC83 to try to get the operating point I use in the EZTube mixer. It won't let be set the HT voltage lower than about 267 volts.  Am I doing something wrong?

Cheers

Ian

Click to expand...

Move the white and yellow arrows first!

There is no limit. I just got 12aX7 plate to 2.9 (!!!) volts.