I am restoring a Kaypro 2000+. (Anyone have OS software disk?)
Anyway, about 12 of the keys do not work. The are Cherry key switches. They are black. They have a spring, copper contacts and a diode. Only other markings are an "A" on the lower left of the switch housing top; a "80" on the bottom of the housing; and a "3" on the plunger that the cap attaches to.
I thik they are Cherry MX series. MX3500 or MX1A-11DW. Not sure. They have three plastic post on bottom to sit in pcb card. I think they only have three soldering post, but maybe 4, I can't tell if there is a soldering post on the upper left.
First, the switched look fine. Unless the diode is bad, hard to tell what an go wrong with these as they are pretty simple device. Having said that, I know I have had key switches on my Tandy Model 102/100 that looked fine but worked after replacement. I looked at the pcb board and can't see anything that indicates broader issues. Again, not sure how to test.
So, I'm going to try and relace the switches to see if that is the issue. What is the difference between Cherry MX brown, blue, black etc. Does color matter?
Any advice?
Anyway, about 12 of the keys do not work. The are Cherry key switches. They are black. They have a spring, copper contacts and a diode. Only other markings are an "A" on the lower left of the switch housing top; a "80" on the bottom of the housing; and a "3" on the plunger that the cap attaches to.
I thik they are Cherry MX series. MX3500 or MX1A-11DW. Not sure. They have three plastic post on bottom to sit in pcb card. I think they only have three soldering post, but maybe 4, I can't tell if there is a soldering post on the upper left.
First, the switched look fine. Unless the diode is bad, hard to tell what an go wrong with these as they are pretty simple device. Having said that, I know I have had key switches on my Tandy Model 102/100 that looked fine but worked after replacement. I looked at the pcb board and can't see anything that indicates broader issues. Again, not sure how to test.
So, I'm going to try and relace the switches to see if that is the issue. What is the difference between Cherry MX brown, blue, black etc. Does color matter?
Any advice?