[Boatanchors] Heathkit HW101 Rx problem

[Drew P.]

Jim wrote:

> I am repairing a Heathkit HW-101, it is transmitting and
> receiving OK after
> electrolytics replacement and rig alignment. Now I have
> delay for the
> receiver to recover after transmitting. The manual says to
> check D101, it is
> OK. I wonder if anybody has experienced this problem
> before?

This problem is often due to screen grid emission in the 6146 final amplifier tubes during receive.  In the SB/HW 100 series, the final screens, the driver screen, and the isolation amplifier screens are all supposed to be at a negative potential during receive, but final screen emission drives the whole lot positive.  The cure is addition of a diode in series with the lead feeding the final screens.

Drew