[R-390] atf4 ballast tube

[Roy Morgan]

At 06:44 AM 12/19/2004, you wrote:
>hello to everyone happy xmas. have just fitted atf4 ballast tube in 390a
>and it seems to be working fine.it glows a little more than a atf7. can
>anyone tell me will this give me any problems. many thanks brian

Brian,

The current delivered to the regulated tubes is likely to be wrong. Do test 
the voltage at the output of the ballast tube to find out.

The ballast tube is likely to not last very long. It is being operated way 
above it's current design range. That's why it "glows a little more".

You would be better off with a fixed resistor.

Roy


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