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  From: Alan Kennington <Alan.Kennington@dsto.defence.gov.au>
  To  : LLEVY@baea.com.au
  Date: Mon, 9 Nov 1998 12:51:14 +1030 (CST)

RE: modems and fluoros

Lea,

In view of the almost-irrelevance of the fluoro/modem problem to
this e-mail list, I'll do a quick summary of the numerous helpful
responses I received.
And I'll avoid posting any more on this.

The theories advanced to me all seem to address the physics of the matter.
Probably in fact I do have a faulty starter capacitor on the light.
But what's still intriguing to me is the fact that
many other people must have similar problems, although I've never
heard anything about this.
Also intriguing to me is the fact that running a reliable MNP
(or whatever) protocol makes no difference. It's just a simple
relation: light goes on, and in less than a second, the modem goes off.
Nothing else seems to be affected.
The surge protection outlets that I use for all my computer
gear do not seem to help.
The noise must go through the mains -- because of the
distance involved.

I'm disappointed that no-one else has had this problem.
The modem is a 9600 bps dataplex 296, which runs nicely 24 hours a day,
a big, industrial-strength-looking modem with its own
built-in power supply.

My hunch is that the fluoro generates a lot of signal in
the frequencies that upset the modem communication -- except that
if the other end of connection is dropped, the modem tries for
about 5 seconds to re-establish the connection.
then why doesn't it try for 5 seconds when the power "surge" happens?

It's just possible that the modem is so "sophisticated" that it
has a built-in cut-out when it thinks a surge is on the way.
The problem occurs identically on two identical modems.

Since modems are quite cheap now, I'll soon get a new modem.
But still, being a scientist by background, I do like to understand
"why it is so".

I was hoping that other people would know of similar experiences.
But obviously not. Then again, it took me 2 years to finally work out
the causes of the "random" drop-out of the modem just after I arrived
home every day.
Maybe you only notice this kind of problem if you keep your modem
running all day. And most people don't do that.

I'll get back to work now.
Cheers,
Alan Kennington.

PS.  Does anyone know the cheapest way to get connected 24 hours a
day, 365 days a year to the net in Adelaide?

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