PDA

View Full Version : Amiga 500 Keyboard Membranes



rwap
18th June 2013, 12:34
How much interest would there be in replacement Matsumi A500 keyboard membranes at 20 each? - I would need to order 250 to get that sort of price (!) so this is only tentative at the moment.

Would these also fit the A500+ ?

rkauer
18th June 2013, 19:25
Will fit in A500+, it have the very same keyboard.

jimbob
18th June 2013, 22:34
Unfortunately I'd have to say that 20 is a bit steep, though I understand why it would be hard to get the price down. Otherwise I think replacement membranes are a great idea, for other models too.

Note that not all 500 membranes are the same as 500+. Some have the extra large return and shift keys instead of the blank/international keys.

lostrego
19th June 2013, 00:29
This would help also: Those membranes will fit in later C= A4000 and Escom A4000T keyboards too, the Mitsumi ones with spring coil for key recoil, not to be confused with the rubber dome ones (mostly found on A2000, A3000 (T) and early C= A4000D that use a circuit board instead of a membrane).

There spring coil ones are basically the same keyboard than the one of the A500 but with few minor differences.

---------- Post added at 00:29 ---------- Previous post was at 00:24 ----------

Note: the above mentioned spring coil A4K/T Mitsumi keyboards all have the extra blank/international keys.

rwap
19th June 2013, 11:10
This is always the problem with the Amiga - which keyboard membrane to produce - I am not sure which A500 one I have - I presume it is the A500 keyboard without the extra blank key (the left hand shift button abuts the Z key) - is that what you mean?

Is that the wrong model, would it be better to produce them for the A500 with the extra shift key - in which case, I need another A500 keyboard and membrane !!

rwap
19th June 2013, 15:43
This is the keyboard I have already - which model is it though?

http://www.rwapsoftware.co.uk/images/Amiga A500 Keyboard.jpg

rkauer
20th June 2013, 21:03
ALL Mitsumi A500 keyboards have the same membrane, disregarding the number of keys over it.

On larger Enter/Shift keys the unused contacts are simply covered by the larger keycaps and the actuators are not installed.

The "rubber coil" keyboards might use membranes or PCB circuits, but the membrane units have the very same connection to the interpreter circuit of the A500 with minor differences in the hardware. The membrane will be always the same.

As far as I knowthe most needed membrane is the green A600 (Mitsumi, again), which is poor in reliability.

jimbob
20th June 2013, 22:25
I don't think that's correct. There are at least two types of A500 membrane, mitsumi part numbers 56 A619A and 56 A619B.

The A part does not have contacts for the extra keys and I'm not sure everything else lines up perfectly either. I can't actually check this at the moment because the ones I replaced have been returned to their owners and I sent the faulty ones to TheRogue who thought he might be able to clone them.

There is also a third type which has a different two part connection to the controller board, not sure about its key contact layout.

@Rwap the one in your pic has the big keys, I guess you better open it up to check whether or not it has unused contacts on the membrane.

rkauer
21st June 2013, 02:18
What I know for sure is the one with extra contacts will fit in the ones with less contacts without any problem.

The ones with two connectors are not Mitsumi, they are made by Samsung.

rwap
21st June 2013, 09:53
ALL Mitsumi A500 keyboards have the same membrane, disregarding the number of keys over it.

On larger Enter/Shift keys the unused contacts are simply covered by the larger keycaps and the actuators are not installed.

The "rubber coil" keyboards might use membranes or PCB circuits, but the membrane units have the very same connection to the interpreter circuit of the A500 with minor differences in the hardware. The membrane will be always the same.

As far as I knowthe most needed membrane is the green A600 (Mitsumi, again), which is poor in reliability.

OK thanks - I will have a look to see if it has the extra contacts - presumably under the Enter key and the bottom left shift key ??

I can look into A600 membranes too - but need a keyboard unit and membrane to do this!

roy_bates
21st June 2013, 11:27
rkauer is saying the membrane for the two mitsumi 500/+ keyboards are interchangable,hes not saying that there is a contact under the bigger keys.


i dont know if you can interchange them though as the key contact/plunger is in the centre of the key,and would put the contact in the wrong place on the membrane.
i do have both as ive just repair two just to find out but it is a bit of a pain to take apart two keyboards find this out.

rwap
21st June 2013, 14:00
rkauer is saying the membrane for the two mitsumi 500/+ keyboards are interchangable,hes not saying that there is a contact under the bigger keys.


i dont know if you can interchange them though as the key contact/plunger is in the centre of the key,and would put the contact in the wrong place on the membrane.
i do have both as ive just repair two just to find out but it is a bit of a pain to take apart two keyboards find this out.

I have just taken a couple of photos (attached) - I agree - it does look as though the two membranes are not interchangeable, as you can see underneath the larger shift key, there is only one contact on the membrane and it is pretty much in the middle of the key - therefore there would not be enough room to add a second contact for the blank / international key...

That is a real shame - I can't see that there will be enough of a market to justify getting two different keyboard membranes made for the two types of keyboard (or maybe I am wrong?)

Which membrane is more likely to be required ? If its the one with the extra keys, then I will need to borrow another keyboard and membrane for that to get the tooling correct

http://www.rwapsoftware.co.uk/images/Amiga A500 Membrane.jpg

http://www.rwapsoftware.co.uk/images/Amiga A500 Membrane2.jpg

jimbob
21st June 2013, 16:43
That there is the A part, as luck would have it I still have one knackered B part. I can send this to you if you want.

Looking at the area from your close up, my one has one key contact to the left and one to the right, I guess the return key is similar. Assuming the rest of the keys are lined up I think the the B membrane would work on A keyboards except for return and left shift keys. Maybe you could make an adjustment like a second contact in parallel for those keys so it would work?

Let me know if you want this membrane.

rwap
24th June 2013, 10:50
Many thanks - PM sent as it would be interesting to see if there could be some way of making the A and B type membranes as one...

I am informed that the A type is the most common anyway (and the version which works with the A500+) (luckily)

If someone has an A600 keyboard and membrane, I could also look at getting membranes for that - how many versions of the keyboard exist?? :p

rwap
27th June 2013, 16:59
Having met with the guys from the membrane manufacturer this morning, and thanks to the B type membrane received from jimbob, this is looking positive.

They think that it should be quite feasible to merge the two membranes so that one membrane will fit both keyboards - although it is of course subject to checking everything!

rwap
3rd July 2013, 21:32
The membrane manufacturers have completed their investigation - they say that the two membranes can be combined - they just need to add 2 switches to the B type membrane - those switches will handle the larger Enter key and the larger shift key

Can someone please confim - is there two larger shift keys on the A membrane or just one?

Ideally I could do with a photo of the two keyboards!

roy_bates
3rd July 2013, 23:05
amiga 500 keyboard:

http://www.amibay.com/picture.php?albumid=191&pictureid=2678

amiga 500+ keyboard:

http://www.amibay.com/picture.php?albumid=191&pictureid=2679

i didnt bother trying to get the numpad in shot there both the same.

i think the pictures speak a thousand words,you could litrally overlay the two to see it around the left shift and enter plus the blanks.

rwap
4th July 2013, 06:55
Many thanks - that has confirmed that the membrane company have identified the correct differences. :)

rwap
7th August 2013, 13:09
Membranes are due to be sent to me next Friday - so I expect to have them by Tuesday 20th !! :D

rwap
24th August 2013, 16:13
Great news - the membrane has now been tested and works great on both the A500 and the A500+ (thanks Roy_Bates for testing) - I shall have them available for sale on Wednesday / Thursday!:D

pkersey
25th August 2013, 01:12
Great news - the membrane has now been tested and works great on both the A500 and the A500+ (thanks Roy_Bates for testing) - I shall have them available for sale on Wednesday / Thursday!:D

That's great. Any news on the Amiga A600 membranes? I need some.

rwap
25th August 2013, 08:37
I have sent one of each A600 keyboard and keyboard membrane to the manufacturer to see if these can be merged also - so we shall see.

Bear with me, as I have several different projects on the go at the moment, and only limited resources - remember that each new membrane run involves a substantial investment of money!

rwap
26th August 2013, 17:17
The A500 Keyboard Membranes will be with me on Wednesday. :D

You can order them (and pre-order the A500 membranes) via: http://www.sellmyretro.com/category/Retro+Computers/Commodore/Amiga/Hardware/General+~~+Add-Ons

pkersey
27th August 2013, 16:42
Thank you very much, Rich!


I have sent one of each A600 keyboard and keyboard membrane to the manufacturer to see if these can be merged also - so we shall see.

Bear with me, as I have several different projects on the go at the moment, and only limited resources - remember that each new membrane run involves a substantial investment of money!

rwap
28th August 2013, 10:02
The A500 membranes are now here :)

roy_bates
28th August 2013, 10:14
what are the differences between the blue and green membranes for the 600 i only have the green.
are these the two peaple are talking about?

Turranius
28th August 2013, 10:52
I really wish to buy 2 or 3 to support you and I might need them, but 20... I don't know. Convince me =)

Also, do you have to register to order from that webpage? Seems like it.

roy_bates
28th August 2013, 11:05
there new,and there better than the mitsumi ones shipped by commodore in my opinion and worth the money.

rwap
28th August 2013, 11:08
Yes, you do have to register to order - the site is my own version of ebay :)

As for costs - they are based on the costs of manufacturing, which have escalated over the past few years (mainly due to the silver price) - there is not a lot of markup, so no room for manoeuvre unfortunately.

On the plus side, the membranes should keep the Amiga going for the next 10-15 years without any problems - maybe even longer.

Roy_Bates has tried out the membrane and can comment on the quality etc as an independent observer - his comment to me was:


"the membrane works in both the 500 and 500+ perfectly.

i would even go so far as to say it was better than the mitsumi membrane."

---------- Post added at 10:08 ---------- Previous post was at 10:06 ----------


what are the differences between the blue and green membranes for the 600 i only have the green.
are these the two peaple are talking about?

I can't comment - as the requirement for blue and green membranes appears to be evenly spread. I didn't see the membranes and keyboards myself (as a third party sent them straight to the manufacturer for me), but the differences are substantial - mainly to do with the locating holes on the keyboard!

roy_bates
28th August 2013, 11:15
oh i see,so its a mechanical fit problem? not an electrical problem.

so the two keyboards are mechanicly different in assembly.but look the same on the outside and fit the same ribbon connector.


also,about the 500/500+ membranes,were talking about something that should be good for 15-20 years.(as long as the controller still works after that) i cant really praise these anough.
personally i think the keyboards for these machines are reletively low maintenace compared to a 600 and 1200 that have there own problems with the ribbon on the membrane being connected directly to the motherboard.

rwap
28th August 2013, 11:16
Yes, I believe so - although as I say, I have not seen them!

Turranius
28th August 2013, 12:36
Ok, I'm sold. Ordered two =)

Thanks!

pkersey
6th September 2013, 16:21
but the differences are substantial - mainly to do with the locating holes on the keyboard!

Hi, Rich! Never seen the blue membrane but wouldn't it be possible to manufacture a membrane that would fit both keyboard types, comprehending every possible cut from both models?

rwap
6th September 2013, 16:27
I did ask a similar question, but only if you want part of the membrane sticking out of one of the keyboards - the keyboards are actually a different size!
:roll:

I have not compared them myself either - but my guess it's the metal backing plate which would not fit in place

ElectroBlaster
18th September 2013, 14:42
Flips I have not been following this!

Get here wallet, you aint running away I want membranes lol

EDIT: Just bought 1 x A500 membrane. Im so glad these are available!
EDIT2: Also gone for a blue-type A600 membrane. Slowly but surely these old miggy's are getting full health :)