Heathkit SB-401 Assembly Manual page 122

IF the CW crystal is missing this will fail
4v P-P on scope ,tune
CW mode
V9 is main driver
Keep in mind all oscillators must work
here or this signal will be wrong, there
are 3 Oscillators mixed, here.
STEP3
STEP4
STEP5
On 3.5mhz, pin2 V9 I got 10v p-p
on the scope, tuned., DRIVER
steps.
The Dummy load connected !
This is final Grid Drive.
CW KEYED !
As much as 120v p-p at antenna too.
STEP6