From ?SteffanDiedrichsen:
You can search the HamTech archives, I've posted some mails on this topic.
Briefly:
#1 - #12 : 50 - 60 mVpp #13 - #24: 15 mVpp #25 - #91: 10 mVpp for old school sound.
My A-100 TGstart at 10 mVpp and rises up to 40mVpp at the top octave. I saw a chart of an RT3, which rised up to approx. 20 mVpp in the treble region. There seems to be some changes in the flavour over the time. Depending on your taste you can create a chart and graph a slightly hanging curve starting at 10 mVpp for #25 and ending at your desired value for #91 (20 mVpp / 40 mVpp).
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