From the data sheet: "The 3-500Z must be operated vertically, base up
or down."
73,
... Joe, W4TV
On 4/3/2014 9:19 AM, Pete Smith N4ZR wrote:
> I need to trouble-shoot my QSK system, which is built into my SB-220.
> Will it do any harm to apply filament and plate voltages, but no drive,
> to the 3-500Zs in the inverted position for a few minutes at a time?
>