Dan,
My 102 arrived from eBay with several dead keys. I traced it down to two cracks
on the circuit board. It took some time but I finally fixed it with some bypass
wires. One of the things I did to diagnose the dead keys was to look at the
schematic and find the two leads that the key should join together when it is
pressed. Then I took my multi-meter and tested the two leads while pressing the
key. The beep or lack of beep from the multi-meter allowed me to trace the
circuit to find the bad spot.If you are just checking for problematic keys,
flip the keyboard over and check the solder points of the key while pressing it
down. That will tell you if you have a dead key or something more.Keep in mind
this is one of those times when you will wish you had three hands.
Kurt
On Tuesday, August 4, 2015 8:45 AM, dano <[email protected]> wrote:
<!--#yiv6378610308 .yiv6378610308hmmessage
P{margin:0px;padding:0px;}#yiv6378610308
body.yiv6378610308hmmessage{font-size:12pt;font-family:Calibri;}--> Hi, my name
is Dan. I’ve owned a M100 since the mid 80’swhere I lugged it around to user
group meetings and college. I even had areally cool setup with a DVI and a
composite green screen monitor to type up reports on.Unfortunately I sold the
DVI to pay for a good chunk of parts to build an IBMXT clone. Now I'd much
rather have the DVI. I saw on the Club 100 page the Rick Hanson hadpassed.
I’ll miss him, he was alwaysvery kind. Over the years I purchased a number of
EPROM’s from him and he refurbisheda couple of M100’s for me. Recently I saw
theNADSBox. I’ve ordered one. In preparation for its arrival I pulled my old
M102out of storage. When it went in tostorage, it was working. Storage is not
climatecontrolled (it’s my garage). The problem I’m having is that the + and
Enter key do notwork. According to the service manual,Figure 4-7 the keyboard
looks to be a matrix style. Asking those more experienced, should I lookat a
key switch problem, bad IC or the ribbon cable connecting the keyboard to the
PCB? Thanks,Dan
