I have never seen this caution printed anywhere. If you are going to
change the
plug in coils in the HBR, be sure that the B plus is turned to standby.
The L2
coil has 250 VDC on the primary winding going to the first stage RF
amplifier.
It is probably pretty obvious but sometimes obvious things slip by us.
Kurt, W6PH (HBR-13C)