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Kaypro II restoration almost done!

vanderk

Experienced Member
Joined
Jun 11, 2009
Messages
69
Location
Sebring, Florida
I picked up a dusty and dirty Kaypro II sometime ago on eBay for around $30.00 less shipping. It was in excellent cosmetic shape but had several electrical issues and some defective ICs. I installed all new electrolytic capacitors in the video and power supply boards (several were leaky), replaced a few resistors, and replaced two problematic 47uf electrolytic caps on the motherboard (C69 and C20). The Kaypro has been upgraded to accept a 2732 ROM (Micro-C), has the "speed up" mod to include a Z80B, and will now work with double-sided drives. I'm getting ready to install a composite video output board. U33, U34, U39, U48, U60, U71, and U73 were upgraded/replaced (e.g., 74LS157 to 74S157). Did I also mention that it had bad soldering at the pads on J5? This is apparently a common problem. I also performed the infamous U87 fix per the Kaypro field service bulletin.

The only cosmetic damage to the exterior was a ping/gouge on the back--almost like someone hit it with a nail. I decided to install the 2.5MHz/5.0MHz SPDT switch at the same location of the gouge.

I'm going to burn the Micro-C ROM tonight and get this unit up and running again!

Here are some pictures of topside of board (I also had to work on the underside and make a few jumpers).

http://kaypro.freeshell.org/KayproII_1.jpg
http://kaypro.freeshell.org/KayproII_2.jpg
http://kaypro.freeshell.org/KayproII_3.jpg
http://kaypro.freeshell.org/KayproII_4.jpg
http://kaypro.freeshell.org/KayproII_5.jpg
http://kaypro.freeshell.org/KayproII_6.jpg
 
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