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#1 2015-01-19 12:17:57

Katsura82
Member
Registered: 2015-01-19
Posts: 2

Macintosh LC III problem

Hi,

I have a Macintosh LC III but I don't have a monitor for it.

I just bought an adapter Mac>VGA with 10 dip switches for connecting the LC III to a VGA monitor. Exactly this: ( http://ep.yimg.com/ca/I/cablesonline_2268_235879606 )

I tried with different CRT monitors and different combinations of the dip switches but nothing appears on the screen (black all the time).

Do I need specific monitors (specific size, specific frequency, ...) or the problem is that those adapters don't work with the LC III?

Thank you very much in advance for your help.

Last edited by Katsura82 (2015-01-19 12:19:37)

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#2 2015-01-19 12:27:39

LCGuy
Administrator
From: Sydney, Australia
Registered: 2014-05-13
Posts: 810

Re: Macintosh LC III problem

Has the Mac been powered up in a while? It may have a dead PRAM battery or no PRAM battery. Try doing what is known as the Pizzabox PowerToggle - turn the machine on, then turn it off and back on again. If the logic board is fine it should boot up normally. If not you may have an issue with bad capacitors, or some other issue with the logic board - if in doubt pop the lid and do a visual check. And if the battery is a red Maxell, remove it!

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#3 2015-01-19 13:51:18

Katsura82
Member
Registered: 2015-01-19
Posts: 2

Re: Macintosh LC III problem

I bought it second hand and the previous owner told me the computer was not used for years.

The computer boots normally (it sounds like it's launching the operative system) but there's no picture on my VGA monitors (some monitors show the message "out of sync"). I think it's a problem of not compatibility with the monitor and I only have VGA monitors. I don't have any Macintosh monitor (RGB) and nowadays is very hard to find one.

Which kind of (VGA) monitor do I need?

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#4 2015-01-20 12:32:19

Dnal
Member
Registered: 2015-01-03
Posts: 58

Re: Macintosh LC III problem

Do you have the instructions for the adapter?  Back in the day, I had one with no instructions on the back.  Try setting it top 640x480 resolution tonstart.  Sounds like the adapter is not set correctly or doesn't work.

Be sure to check the battery anyway.  Those Maxells are nasty if they go.

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#5 2015-02-23 19:32:26

360alaska
Member
Registered: 2014-12-04
Posts: 15

Re: Macintosh LC III problem

I know it's been a month, but people are always asking this... This is the instructions for the adapter I have, I'm guessing your adapter is a copy of this one...



https://docs.google.com/file/d/0B_Xp3uN … WxCaUdoYTA

Last edited by 360alaska (2015-02-23 19:33:05)

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#6 2015-02-23 21:46:02

uniserver
Member
From: Sf, Mi
Registered: 2014-05-15
Posts: 955
Website

Re: Macintosh LC III problem

the LC-III is also known for not giving you video when the caps are bad.


#I Re-Cap √Mac √NeTX √Amiga Boards - A/B - PSU# (MacCaps.com)  Modern SCSI HD's - For Old Macs - Pre Cfg'd - 10k RPM! 73gb!! $50 + free shipping  -- Mac 128K Re-Ram kits (16 Chips) $35 + shipping, Floppy Issues?-> Bourns Filter Solution 128k - SE/30, $16 + shipping

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#7 2015-02-23 23:02:09

techknight
Member
Registered: 2014-05-22
Posts: 449

Re: Macintosh LC III problem

Well, these days its not "if". Its when...

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#8 2016-11-20 11:12:01

AlpineRaven
Member
Registered: 2016-10-08
Posts: 4

Re: Macintosh LC III problem

If the battery is good it'll show a video - but it is quite common it does not show video if the battery is dead or flat/missing.
Out of sync - try change dip switch settings, mine one is set for 17" display and works well.
Cheers
AP

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