Actually it's not an "HP" arguement, it's a universal
electrical/electronics arguement.

In theory....... a mechanically activated switch can "arc" which could
send a "spike" down the line and damage some of the input buffers.

The newer "intelligent" switches use electronic devices to do the
switching which eliminates both the arc and the spike.

If you use the older style mechanical switch, how much damage will be
done?
Who knows.....  I've seen systems with A/B switches that have been in use
for --years--.
But the *possibility* of damage exists, so printer makers caution against
their use.



Jim Meagher
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-----Original Message-----
From: David Grossman <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
Date: Thursday, January 28, 1999 2:00 AM
Subject: Re: [PCBUILD] HP Office Jet 520 and HP 722C


>I'd like to hear more comments about HP's argument that an A/B switch box
>will damage a computer. I have not found that to be the case with many
>printers that I have set up. What is their reasoning?
>
>Granted, there may be a problem with the printer recognizing the driver
if
>it isn't switched to the printer before loading Windows. And it's also
true
>that it you accidentally send a document with a different printer setup
>you'll get a lot of gibberish. You'll waste paper and ink. However, I
don't
>see how you will damage the printer by doing so.
>
>
>the At 13:48 27/01/99 -0500, you wrote:
>>Posted on behalf of Susan Hays ([log in to unmask]),
>>         by moderator, Elizabeth Boston
>>
>>
>>
>>Be patient this is my first time to do this.  I have an
>>Office Jet 520 and a HP 722C printer.  I was told the only
>>way I could use my
>>722C as my primary printer was to add another parallel port
>>to my computer.
>>Otherwise the Office Jet 520 would take over as the printer,
>>no matter what.  I
>>was also told that an A/B switch would damage the HP722C
>>printer and HP would
>>not hold up their warranty if an A/B switch was used.
>>         Does anyone have any other solutions besides adding
>>another parallel port?  Is there an easier way?  In the
>>meantime, is there any way I can use my Office Jet 520 as a
>>fax machine?  Sure could use some expert help.
>>
>>Thank you,
>>Susan S. Hays
>>
>>            Do you want to signoff PCBUILD or just change to
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>>
>
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