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geekhack Community => Keyboards => Topic started by: csharper19 on Sun, 26 June 2011, 07:32:48

Title: cheap capacitive keyboard
Post by: csharper19 on Sun, 26 June 2011, 07:32:48
Well..
Any ideas for CHEAP capacitive (&Mechanical) keyboard ?

Thanks.

BTW,
I got IBM Model M (don't know the model , I'll take pictures TOMORROW) in Hebrew/English Keys,
and Cherry PoS [Brown / Clear] from eBay.

Pictures Tomorrow.
Title: cheap capacitive keyboard
Post by: bhtooefr on Sun, 26 June 2011, 07:43:36
You could get a BTC foil and foam keyboard... *runs*

What's your definition of cheap, though? The Model F meets that definition, if you can find one cheap.
Title: cheap capacitive keyboard
Post by: keyboardlover on Sun, 26 June 2011, 08:08:42
Compaq MX11800 and Dell AT101W are always good cheapy mechanicals on ebay.
Title: cheap capacitive keyboard
Post by: bhtooefr on Sun, 26 June 2011, 08:14:51
They're not capacitive, though.
Title: cheap capacitive keyboard
Post by: keyboardlover on Sun, 26 June 2011, 08:16:24
Ohh missed that part :D
Title: cheap capacitive keyboard
Post by: bhtooefr on Sun, 26 June 2011, 08:18:50
I simply have to ask how you missed that part.

The thread title is "cheap capacitive keyboard" - my emphasis. ;)
Title: cheap capacitive keyboard
Post by: keyboardlover on Sun, 26 June 2011, 08:22:25
I can't read?
Title: cheap capacitive keyboard
Post by: The Solutor on Sun, 26 June 2011, 08:43:15
Quote from: csharper19;368355

Any ideas for CHEAP capacitive (&Mechanical) keyboard ?

 
Unless you think to the virtual keyboard of the iphone or similar, any capacitive keyboard is mechanical.
Title: cheap capacitive keyboard
Post by: Findecanor on Sun, 26 June 2011, 09:16:11
Why does it have to be capacitative? New capacitative keyboards are rare these days.

"Foam and foil"-keyboards have either springs (linear) or rubber sleeves (tactile) to provide the resistance, but they have a mushy landing because of the foam.
Title: cheap capacitive keyboard
Post by: theferenc on Sun, 26 June 2011, 09:35:15
Does it have to be usable with a modern computer? You can often find XT Model F keyboards for cheap.
Title: cheap capacitive keyboard
Post by: bhtooefr on Sun, 26 June 2011, 09:45:13
For that matter, Soarer's Teensy-based adapter will make an XT F usable with a modern computer.
Title: cheap capacitive keyboard
Post by: theferenc on Sun, 26 June 2011, 09:46:12
That's true. Now I need to find a socket I can solder on to my teensy...
Title: cheap capacitive keyboard
Post by: IvanIvanovich on Sun, 26 June 2011, 09:48:47
Vintage ones are your best bet, but can be hard to get ones for cheap that are in good condition, or that work on modern hardware without extreme modding. Sometimes the foam ones turn all brittle and feels like typing on rice crispies, or just goes to dust and renders it non working. The only capacitive switch I would even consider bothering with is Topre, and those certainly are far from cheap. If you're just curious about other switches you'd have better luck finding some decent Alps boards, and you'd likely find them more enjoyable.
Title: cheap capacitive keyboard
Post by: bhtooefr on Sun, 26 June 2011, 10:02:38
Hey, capacitive BS is quite good, too. Very, very different from Topre, but quite good.

(Basically, Topre is a really, really good rubber dome. If you like that sort of thing, it's great. Capacitive BS is a really, really good buckling spring switch.)
Title: cheap capacitive keyboard
Post by: The Solutor on Sun, 26 June 2011, 10:14:13
Quote from: bhtooefr;368403
Hey, capacitive BS is quite good, too. Very, very different from Topre, but quite good.

(Basically, Topre is a really, really good rubber dome. If you like that sort of thing, it's great. Capacitive BS is a really, really good buckling spring switch.)

 
Completely agreed.

BTW I still cant understand why all you are calling switches, the capacitive sensors.

To be called "switch" the sensor and the switch logic should be a single block with the capacitive sensor and the electronics inside it, this kind of switch exist and is used mainly industrial equipments.

On the other hand a capacitive keyboard is a matrix of capacitive sensors connected to a logic which convert the sensors input in digital signals, the switch part is completely skipped.
Title: cheap capacitive keyboard
Post by: IvanIvanovich on Sun, 26 June 2011, 10:24:04
I don't like Bucking Spring personally, but I really have nothing against them either. OP already has one, so I didn't see any reason to bring them up. Though it could be a membrane version model. If its capacitive then i guess the search is over, as they would already have what they are looking for.
Title: cheap capacitive keyboard
Post by: alaricljs on Sun, 26 June 2011, 10:37:27
Because it's easier than being pedantic.
Title: cheap capacitive keyboard
Post by: The Solutor on Sun, 26 June 2011, 10:39:49
Quote from: alaricljs;368420
Because it's easier than being pedantic.

 
Instead I find that being informed in not more difficult than living in the ignorance.

But it's just me, I'm strange I know.
Title: cheap capacitive keyboard
Post by: theferenc on Sun, 26 June 2011, 10:56:16
Well, to be pedantic, a switch is actually just something that actuates a circuit, or directs an electric flow. So, to be pedantic, buckling springs are, in fact, switches: when pressed, they actuate a circuit, and direct the flow of electricity within the logic board to produce a specific key stroke. Topre domes are also switches, as they change the capacitance of a circuit, thereby changing the flow of electricity within the circuit board, thereby producing the key pressed.

Don't be pedantic unless you are actually going to be pedantic. If an action occurs in an electrical system due to the pressing of a button, it is, according to the definition of the word, a switch. Technically speaking, each and every logic gate in your CPU is a switch.

If you were actually informed, you would know that.
Title: cheap capacitive keyboard
Post by: keyboardlover on Sun, 26 June 2011, 10:58:14
Where can I find a keyboard with pedantic switches?
Title: cheap capacitive keyboard
Post by: theferenc on Sun, 26 June 2011, 10:59:18
Best Buy sells them.
Title: cheap capacitive keyboard
Post by: alaricljs on Sun, 26 June 2011, 11:00:33
Told you it was easier than being pedantic.
Title: cheap capacitive keyboard
Post by: theferenc on Sun, 26 June 2011, 11:05:26
Totally. But I hate it when people act all pedantic, but then are wrong.
Title: cheap capacitive keyboard
Post by: The Solutor on Sun, 26 June 2011, 11:11:23
Quote
Well, to be pedantic, a switch is actually just something that actuates a circuit,


Yes and a capacitive sensor  doesn't.

This is the wikipedia definition of electrical switch.

Quote
In electronics, a switch is an electrical component that can break an electrical circuit, interrupting the current or diverting it from one conductor to another.


Quote
So, to be pedantic, buckling springs are


Bucking spring is not a switch technology it refers just to the mechanical part of the switch.

So a membrane BS is a switch while a capacitive one doesn't

Quote
when pressed, they actuate a circuit, and direct the flow of electricity within the logic board to produce a specific key stroke. Topre domes are also switches, as they change the capacitance of a circuit, thereby changing the flow of electricity within the circuit board, thereby producing the key pressed.


Given that definition anything should be considered a switch, and while this can be considered more or less correct, in technology definitions are meant to narrow a range of devices, not to be vague and philosophically debatable.

So a switch is a couple metal contacts meant to be easily connected by contact, or anything else that mimic this behavior being electrically equivalent to the former.

And capacitive sensor (a variable capacitor) is not, definitely.


So to be concise and not pedantic you are just wrong.
Title: cheap capacitive keyboard
Post by: The Solutor on Sun, 26 June 2011, 11:16:01
Quote from: theferenc;368439
Totally. But I hate it when people act all pedantic, but then are wrong.

 
So you gave us an example.
Title: cheap capacitive keyboard
Post by: theferenc on Sun, 26 June 2011, 11:24:55
Wow. Just wow.
Title: cheap capacitive keyboard
Post by: PlayerZero on Sun, 26 June 2011, 12:59:23
I... I don't understand...  Maybe I should get myself a degree in EE
Title: cheap capacitive keyboard
Post by: daerid on Sun, 26 June 2011, 13:00:54
I'm so glad I ignored that guy

Quote from: PlayerZero;368501
I... I don't understand...  Maybe I should get myself a degree in EE

 
I grew up with a master electrician and EE for a dad, and theferenc is 100% correct. Solutor seems to be just picking an argument, like usual.
Title: cheap capacitive keyboard
Post by: PlayerZero on Sun, 26 June 2011, 13:14:21
Quote from: daerid;368504
I grew up with a master electrician and EE for a dad, and theferenc is 100% correct. Solutor seems to be just picking an argument, like usual.

Whatever you say...
Title: cheap capacitive keyboard
Post by: bhtooefr on Sun, 26 June 2011, 13:26:02
A capacitive sensor is part of a capacitive switching system.

The buckling spring mechanism (or, in the case of Topre, the rubber dome and spring) and the capacitive sensor make up one capacitive switch. The sensors are all on a common PCB, and controlled by a common controller, yes, but that doesn't mean that they're not a part of multiple separate switches.

Anyway, the OP has a Model M, which is membrane by definition.
Title: cheap capacitive keyboard
Post by: DaemonRaccoon on Sun, 26 June 2011, 13:48:52
I have a capacitive keyboard, a Gateway2000 manufactured by Maxi Switch in Mexico back in '98. Each key has it's own dome, on a single capacitive sheet, mostly MX compatible keys (stabilizers are quite different), Orange PS/2 plug.

EDIT: It may not be capacitive...
Title: cheap capacitive keyboard
Post by: alaricljs on Sun, 26 June 2011, 13:50:44
.
Title: cheap capacitive keyboard
Post by: ch_123 on Sun, 26 June 2011, 15:07:35
I think it would help if the OP said why exactly he wants a capacitive keyboard in particular.
Title: cheap capacitive keyboard
Post by: The Solutor on Sun, 26 June 2011, 15:51:41
Quote from: bhtooefr;368517
A capacitive sensor is part of a capacitive switching system.

 
A capacitive sensor is part of a capacitive sensing system, the output can vary depending the appliance, could be a digital signal, could be an analog one, could be just a contact.

Quote
The buckling spring mechanism (or, in the case of Topre, the rubber dome and spring) and the capacitive sensor make up one capacitive switch.


No, build up a capacitive key, which is the end function, not a switch which is a definite electrical component.

Quote
The sensors are all on a common PCB, and controlled by a common controller, yes, but that doesn't mean that they're not a part of multiple separate switches.


Does mean they are part of a multiple separate keys. Switchless keys.

Quote
Anyway, the OP has a Model M, which is membrane by definition.


And which is a matrix of switches.
Title: cheap capacitive keyboard
Post by: bhtooefr on Sun, 26 June 2011, 16:55:22
A switch is something that switches something between off and on.

Therefore, even a flat membrane keyboard has switches, because you switch the key off or on.

But, seriously, you need to get the stick out of your ass and become far less of a pendant.
Title: cheap capacitive keyboard
Post by: The Solutor on Sun, 26 June 2011, 17:17:38
Quote from: bhtooefr;368590
A switch is something that switches something between off and on.

 

An electrical switch is something that doesn't switches "something", it switches an electrical circuit from open to closed and viceversa.


Quote
Therefore, even a flat membrane keyboard has switches, because you switch the key off or on.


A keyboard's membrane, indeed is a switch, and I wrote it twice.

Quote
But, seriously, you need to get the stick out of your ass and become far less of a pendant.


IMNSHO, is better being pedantic and right than rude and wrong.
Title: cheap capacitive keyboard
Post by: ch_123 on Sun, 26 June 2011, 17:41:39
There are multiple types of switching. Ohmic (i.e. involving the flow of electric current) is but one of them. If you look at any of the patents or technical documents on the varying types of keyswitches, they will talk about things such as "capacitive switching" or "hall effect" switching even though they are not ohmic in nature. As bhtooefr has said, it makes sense when viewed in context of what the mechanism as a whole is doing, not just focusing on its constituent parts.

Don't believe me? Go and read the patent for the Beam Spring, the other Beam Spring patent, the original IBM buckling spring patent, the Model F patent, the Topre patent, and probably a few others that I haven't got around to reading myself :P

I'm not going to argue with the people who actually designed this stuff, I think they probably know more than me or just about anyone else around here.
Title: cheap capacitive keyboard
Post by: The Solutor on Sun, 26 June 2011, 18:41:06
Quote
f you look at any of the patents or technical documents on the varying types of keyswitches, they will talk about things such as "capacitive switching" or "hall effect" switching even though they are not ohmic in nature.


http://www.wikipatents.com/US-Patent-4472758/capacitive-switching-device

Is not a case that some related patents, mention a "capacitive switching device" and not a switch and they refers to the final result (e.g. mechanical part, sensing device, related electronics).

Quote
As bhtooefr has said, it makes sense when viewed in context of what the mechanism as a whole is doing, not just focusing on its constituent parts.


Indeed is correct to call the whole keyboard "capacitive keyboard", or the key "capacitive key", is less correct call switch something that is a sensor and not a switch.

Quote
I'm not going to argue with the people who actually designed this stuff


I'm used to argue when I think I'm right, not depending who I'm facing. I argued with one of the boss of MS when XP was presented, who was sure that the new (at the time) activation method was unbreakable, we all know how unbreakable is (and was)
Title: cheap capacitive keyboard
Post by: Pylon on Sun, 26 June 2011, 19:05:03
Quote from: DaemonRaccoon;368525
I have a capacitive keyboard, a Gateway2000 manufactured by Maxi Switch in Mexico back in '98. Each key has it's own dome, on a single capacitive sheet, mostly MX compatible keys (stabilizers are quite different), Orange PS/2 plug.

EDIT: It may not be capacitive...

Probably not. It's probably just a single layer membrane with carbon contacts embedded in the rubber domes. I have a Maxi-Switch made Gateway Anykey which does that.
Title: cheap capacitive keyboard
Post by: bhtooefr on Sun, 26 June 2011, 19:06:39
Quote from: The Solutor;368596
IMNSHO, is better being pedantic and right than rude and wrong.

 
Even better to be rude, but right, rather than pedantic, rude, and wrong.
Title: cheap capacitive keyboard
Post by: The Solutor on Sun, 26 June 2011, 19:11:40
Quote from: bhtooefr;368645
Even better to be rude, but right, rather than pedantic, rude, and wrong.

 
Do whatever you want with your life, if you want to learn something I'm here, if you don't I couldn't care less.

I'm used to open my mouth when I have something to tell, and to keep my ears open when I have something to learn, looks like you are used in the opposite way.

No problem for me.
Title: cheap capacitive keyboard
Post by: theferenc on Sun, 26 June 2011, 19:24:49
I'm still curious as to what this is for. csharper, I apologize for the argument that occurred in your thread, hopefully you're still paying attention to it.

And chance you could share your plans for the keyboard?