HQ-170a change from HQ-170

[Floyd Sense]

I've been unable to locate an HQ-170A schematic on the Web, so: I believe that one of the improvements made in the HQ-170A in relation to the HQ-170 was to provide filament voltage to the HF oscillator tube even when the receiver is turned off.  Can someone with a 170A diagram verify that?  If true, was this the only tube supplied with this filament voltage?  Were there changes in the AVC circuit in the 170A vs the 170?

K8AC
Floyd Sense in Angier, NC
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://puck.nether.net/pipermail/boatanchors/attachments/19990419/f6968931/attachment.html>