On 05/05/2019 13:47, Dave Plowman (News) wrote:

In article ,
Mike Clarke wrote:

[snip]

Yes, I appreciate that but I was curious why there should be different
limits for the two ends of a (symmetrical) tube.

Because the capacitance is the cable? And the ballast may not be central?

But they seem to imply that the maximum acceptable capacitance of one
lead is less than the other.

In other words, capacitances of 100pF and 200pF and lengths of 1 metre
and 2 metres is fine but equal length leads of 150pF and 1.5 metres long
would not be acceptable.

It's a bit of an academic point anyway, you'd be hard pushed to exceed
those length limits on a 6ft tube.