Re: Will pay good money for NON working PET 2001 motherboard.

From: Philip Lord <random6000_at_mac.com>
Date: Sun, 08 Nov 2009 21:54:28 +0900
Message-id: <C0A71222-91C5-4967-A582-D8BC793314B6@mac.com>
Hi William,
Thanks for he reply.
For my own education, I was wondering why you feel the the transistors  
are the issue?
I'm also wondering how exactly would you test for a short in a  
transistor??? Is that something that can be done in circuit  with a  
multimeter?

I'll take your advice on dismantling the keyboard and cleaning with  
alcohol. I'll need to be especially careful as this keyboard is  
actually a Japanese variant with Japanese characters also printed on  
the keys.

Thanks again
Phil


On Nov 8, 2009, at 2:10 PM, William Levak wrote:

> On Sun, 8 Nov 2009, Philip Lord wrote:
>
>>>> First thing I noticed was that there were many keys not working or
>>>> working sporadically, however I was still able to quickly write a
>>>> 'hello world' program to confirm that the basic was function
>>>> correctly. All seemed good until I tried to load a tape. After  
>>>> typing
>>>> 'LOAD' and pressing return the computer would freeze. I would not  
>>>> get
>>>> the 'press play now' message, and the tape drive would no longer
>>>> function. Turning the machine off and on again brought the machine
>>>> back to life, and the tape drive was able to move again through FF,
>>>> REW and PLAY buttons. Typing LOAD or SAVE would lock everything up
>>>> again.
>
> Sounds like a short in the cassette moter switching transistors, Q1  
> - Q6.
>
> Problems with the keys is normal for these computers.  First thing  
> to try is to take apart the keyboard and clean the contacts with  
> alcohol.
>
>
>      Message was sent through the cbm-hackers mailing list


       Message was sent through the cbm-hackers mailing list
Received on 2009-11-08 13:00:04

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