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Re: Plant substrate [?] mystery- IDIOTIC REPLYS

> From: George Booth <booth at hpmtlgb1_lvld.hp.com>
> Subject: Re: Plant substrate [?] mystery- IDIOTIC REPLYS
> [...]  

> Since my dictionary describes a "prig" as "one who is precise to an 
> extreme in attention to principle or duty", I think they are more 
> than welcome on this list.  I would take that as a compliment.

Commas go before the quotes.  Are "grammar prigs" more than welcome?

All kidding aside, I have a lighting question.  I'm building a new
4 4' bulb T8 fixture for my 55, following George booth's smart
split-folding design.  Since electronic ballasts for running 4 bulbs
are hardly more expensive than ones for 2 bulbs, I'd like to run only a
single ballast.  I intend to use an instant-start ballast, which is
wired up differently than rapid-start.  

Is there a safe way to switch off the two bulbs on the front half
of the fixture without causing premature wear on the either the bulbs
or the ballast?  If the ballast is really a constant-current source,
switching the leads to the bulbs may load the source too heavily, at
least until it switches off the current to the open circuit (I'd be
using a parallel ballast).  

Also, do high-ballast-factor ballasts (ones that draw more watts to
burn the bulbs a bit brighter) shorten the life of the bulbs 

In dreary but warm Urbana, Illinois,

 John Pitney         pitney at uiuc_edu