On Wed, 15 May 2019 18:02:53 -0700, Michael Terrell wrote:

These simple generators were intentionally distorted. They were over
driven for three reasons.

The first was to make sure that the output didn't drop out and kill the
oscillation at the high end of each band.

The second was to produce harmonics on the higher bands.

The third was to allow the unit to continue to operate as the tube aged.
As far as the coils failing, some adsorbed moisture, which lowered their
'Q'.

Often, the 400 or 1,000 Hz tone was distorted, as well due to the lack
of AGC. It gave a distinct sound in the receiver being aligned. Look at
what HP did in their 606 and 608 series generators to produce a clean
signal. They certainly didn't attempt to do it with two tubes!

Very interesting, thanks!



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