There is a problem with one of the components in the Meade 12 - 18 volt
convertor, where the off load voltage is 18 but when plugged into the LX200,
under load conditions, drops to 12 volts.
The flyback inductor controlling the voltage change developes a shorted turn
over time (heat) and prevents the circuit performing as it should.
Normally there is nothing wrong with the chip.
My internet site has details of rewinding the inductor to clear the problem.
This has always been the cure.
I've copied the relevant section below:-

'Must handle at least 3 amps (Meade = 94 turns of 24SWG Enamel wire on
original bobbin for 330uH, saturated in Polyurethane - original fault showed
low conversion once the chip had been changed - due to inductor turn short
circuit)'

Best regards, BrianB.

Brian Bond
www.brianbond.eu.com

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----- Original Message -----
Sent: Monday, November 03, 2003 6:13 AM
Subject: [M]: RE: RE: Re: LX200 10" on Battery Power


> For what it's worth...when on battery (I use one of Jim Kendrick's
> battery packs with his 12-18 VDC Converter), I don't notice any
> different current indication or speed than when using the 110V-18VDC
> supply from Meade.
>
> Perhaps your 12-18 volt converter is not supplying anything close to 18
> volts? I think I'd measure the output when connected and driving the
> scope, and compare it with the readings when you use the AC line
> adapter. The higher indicated currents is consistent with lower input
> voltage, and is harder on the motors...
>
> Regards,
>
> Bill Beeman
>
> > -----Original Message-----
> > Christian Molnar
> > Sent: Sunday, November 02, 2003 9:48 PM
> > Subject: [M]: RE: Re: LX200 10" on Battery Power
> >
> >
> > Hey John!
> >
> > Thanks! That at least confirms that what I'm seeing may be
> > ok for battery power conditions. The only thing I don't like
> > is that it really sounds like it's not moving nice and
> > smooth. GOTOs are not affected though, so I guess it must be
> > ok. I was worried that tracking may be affected.
> >
> > I guess the next test is to run it until the battery gets low
> > and see how many nights that is.
> >
> > Thanks!
> >
> > Christian.
> >
> > -----Original Message-----
> > Sent: Sunday, November 02, 2003 4:18 PM
> > Subject: [M]: Re: LX200 10" on Batter Power
> >
> >
> > Christian,
> >
> > I'm not sure how this answers your question but...
> >
> > We have not run either of our LX's in AC power in years but I
> > do note that
> > running it on a 33 amp/hour battery with a full charge, it
> > usually bounces
> > between 4~5 LED's. Not sure if this adds to the factors but we run in
> > Alt/Az which probably spends more time with two motors
> > running, use a Meade
> > hard dew shield , 2" diagonal and ep's.
> >
> > John & Bobbie Hilliard
> > Chicago
> >
> > "For my part, I know nothing with any certainty,
> > but the sight of stars makes me dream."
> > ~Vincent van Gogh
> > ----- Original Message -----
> > Sent: Sunday, November 02, 2003 6:07 PM
> > Subject: [M]: LX200 10" on Batter Power
> >
> >
> > Hey Guys,
> >
> > I just finished a power box, marine deep cycle battery inside a metal
> > toolbox with 5 cigarette lighter outlets on top and leads for
> > my inverter.
> >
> > I don't know whether this is just my paranoia but, since I
> > just did this, I
> > noticed it. When I run my LX200 on outlet power (from the
> > house) it is very
> > fast and there are only 3 leds turned on on the indicator
> > most of the time.
> > When I use this power box, you can tell it's moving slower
> > and it is just
> > very different. There's more between 4 and 5 led turned on
> > constantly and
> > it peaks every time it slews. The slews are more sluggish
> > and the motors
> > don't sound like they do when the scope is plugged in.
> >
> > Is this normal? I can't see how this battery wouldn't be
> > powerful enough.
> > It's like a 75 amp hour boat battery.
> >
> > Thanks!
> >
> > Christian.
> >
> >
> >
> >
> >
> >
>
>
>
>

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