>
>> The fly in the ointment is that the AL-1500 tank L gets mucho hot with
>> one 8877. With two tubes and 2x the I-anode, figure c. 4-times as much
>> tank loss.
>
>You will need a minimum of 1/4 inch tubing for 20 through 10 meters, and at
>LEAST
>#12 wire for 160-80-40 meters. The coil form should not be any kind of
>plastic, as
>it will melt. Even the old robust B&W 800 series tank coil assemblies
>experience plastic
>coil spacer failure at powers above 3 kw or so. Duplicating the Alpha
>77SX/DX tank is
>not a good idea either, as it was designed for a plate load of 2100 ohms or
>so. Your
>plate load with 2 X 8877's will be half that with 4 kv on the anodes. If
>chassis space
>allows, I use a Multronics or Henry roller coil along with a 1/4 inch
>copper tubing coil
>for 10 meters.
>
Amen, Phil. For 24A (2A x Q=12) of circulating current at 10m, 3/8" Cu
tubing is not too large.
>
>
>
Rich, AG6K, 805-386-3734, www.somis.org / new e-mail adr r@somis.org
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