Why is my '5' key not working?!

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kieranhj
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Why is my '5' key not working?!

Post by kieranhj » Sat Oct 10, 2015 9:11 pm

Now my Master is up & running it's developed an annoying fault - the '5' key has stopped working. Of course I can type '5' using the numeric keypad but getting a '%' out is a complete PITA! Any ideas what's going on here? Doesn't seem to be just sticking as I can't anything out of it, unlike my occasionally intermittent 'N'..

Thanks all. :)
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danielj
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Re: Why is my '5' key not working?!

Post by danielj » Sat Oct 10, 2015 9:16 pm

It's going to be the keyswitch being grubby. Before getting medieval on it and replacing it (or stripping it down), get some Servisol Super 10, squirt it in, and hammer the heck out of it.

Second step is to desolder the switch, undo it and give it a good clean:
http://deskthority.net/wiki/Futaba_low-profile_linear

If that completely kills it or doesn't work, the third step is to order a new one from retroclinic :)

d.

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hoglet
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Re: Why is my '5' key not working?!

Post by hoglet » Sat Oct 10, 2015 9:32 pm

Have you tried just giving it a good hammering for a few minutes? This fixed all of my "not working" Master keys.

Dave

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1024MAK
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Re: Why is my '5' key not working?!

Post by 1024MAK » Sat Oct 10, 2015 9:35 pm

Some Master keys (and similar on other computers, not just Acorn's) suffer from contamination of the key switch contacts.

Sometimes repeatedly pressing and releasing it (hammering it, but gently...) will break down the contamination. But you normally need to do this up to 50 times (yes, 50). If this makes no difference, do as Daniel suggests.

Similarly, if you don't use the keyboard for a while, you will have to do this again :(
So use it everyday (he said, failing to find time to do this himself :mrgreen: ).

Mark

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Re: Why is my '5' key not working?!

Post by DutchAcorn » Sat Oct 10, 2015 9:52 pm

If you do need to disassemble, there is no need to take the switch apart completely. You can follow this guide up unil
"To dis-assemble, using some pliers grip each pin on the base in turn and "unscrew" them"

You will find that one or both of these pins is blackened. Clean it so that it shines again and screw it back in. Then refit the keyswitch to the keyboard.
Paul

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tricky
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Re: Why is my '5' key not working?!

Post by tricky » Sat Oct 10, 2015 10:42 pm

Sorry, can't check those guides now, but if you do clean the pins, only take one out at a time. The thread is quite steep, one turn is nearly a quarter of an inch, or it was on the one key I had that practising track and field on it didn't fix it!

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Re: Why is my '5' key not working?!

Post by kieranhj » Sun Oct 11, 2015 9:13 am

Thanks for the advice everyone. I will start with a good hammering and take it from there..!
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Re: Why is my '5' key not working?!

Post by flaxcottage » Sun Oct 11, 2015 1:58 pm

DutchAcorn wrote:If you do need to disassemble, there is no need to take the switch apart completely. You can follow this guide up unil
"To dis-assemble, using some pliers grip each pin on the base in turn and "unscrew" them"

You will find that one or both of these pins is blackened. Clean it so that it shines again and screw it back in. Then refit the keyswitch to the keyboard.
Definitely the way to go. I had a keyboard with 13 keys that weren't working! In the end I took all the key caps off and gave it a thorough clean as well. Looks and works like new. And just think of all the Electrons that will feel safer, now. :twisted:
- John

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Re: Why is my '5' key not working?!

Post by BeebMaster » Sun Oct 11, 2015 5:30 pm

Whilst waiting for your hammering to take effect, you can use *FX254,0 to make SHIFT work with the numeric keypad. Once you've got a % on the screen (or use VDU37 if that doesn't work) you can programme a function key to do it for you with *KEY0 and then copy the printed character into the definition.
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