CA3146E Chip - Disk II

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CA3146E Chip - Disk II

Well i seem to of  found the issue with writing to disks with my DISK II drive.  The Transistor in the CA3146E chip that drives the Q2 right/Write  Transistor is shot.  all the others on the chip test ok, but pin 8 is dead..

Seems like this is now a discontinued part.  I have 3 Ebay  ones coming from China, with an ETA of Oct/Nov.  Anyone have a better source?  Digikey/newark/etc all fail to find it..  I am not interested in paying as much shipping as the cost of a DISK II drive to get it here (Canada)..

 

Thanks

 

 

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CA3146E chip source

Try Jameco:  https://www.jameco.com/z/CA3146E-Major-Brands-High-Voltage-5-Transistor-Array-14-Pin_2289055.html

 

They show 39 in stock.

 

 

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gottj wrote:Try Jameco: 
gottj wrote:

Try Jameco:  https://www.jameco.com/z/CA3146E-Major-Brands-High-Voltage-5-Transistor-Array-14-Pin_2289055.html

 

They show 39 in stock.

 

CHIPS came in today .. drive works!  Loaded karateka to a disk   haven't heard those awesome sounds in 35 years ..

But no color everything is blue on black ... using an Amazon composite to hdmi adapter... have issues getting a stable image even as is   time for more digging.   

 

 

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My Europlus used to do that...

My Europlus used to show blue instead of black.

It took me ages to discover there are trimmer pots for colour.

On the board itself there is one between F and H on the right hand side.

If you have a PAL card, there are an addiional two on the card itself at the top. (I mistook mine for polycaps :-D )

 

Remember to mart their position before you fiddle, and only change one thing at a time :-D

 

Hope this helps.

 

Chesh

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Well I thought i had a

Well I thought i had a working drive last night.  Tried some more Disks today, and gettings lots of track errors while trying to format them with copy II Plus.  Drive speed test shows good.  Track error is not consistent even on the same disk.  One disk i retried 3x and it then formated completely.  

 

Bad Disks or still something wrong with the drive or controller? 

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DISK II

Still working this though.. very strange.  Commerical disk show no errors when verifing a disk in Copy II.  Disks that format with Copy II will show Errors something, but not always and not consistent.  However, ADTPro seems to be able to format and write disks with no issue so far (only done 3 of them).  Disks rarely format with Copy II, or original Prodos Disk, Even a disk that formatted previously has issues.  

 

Still trying to figure out the source of the issue, most of the stuff i have been finding online really only dead with consistent issues not these intermitent ones.  

 

 

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