> Something that I've paid notice to only as of late in the
> 3-500Z tube
> is a gradually increasing orange or light red colored glow
> in the
> metallic cooler wings(?) as one sends CW of SSB during an
> "over". Is
> it normal for the tube to begin glowing like that, or is
The tube must show red on the anode or it will not degass.
The gettering material in a 3-500Z is coated on the anode.
Also the anode gets rid of heat primarily by infrared
The lingering red you notice is probably thermal lag in the
anode. It takes a while to cool after heating. If the idle
current goes to zero on standby or to around 70-100mA
between dots and dashes all is normal.
> The SWRs on my antennas are below 2:1,
SWR has nothing to do with anything except arcing in the
tank loading capacitor or not being able to tune.
tube plate current around
> 450-500 mA (which I guess is stretching it a bit), and
> grid current
> around 200 mA. Output according to a Daiwa meter is
> between 700 to
> 1000 watts depending on the band.
The grid current sounds a bit high, like you could advance
the loading control slightly more.
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