"Gareth Magennis" <
sound....@btconnect.com> wrote in message
news:xvudncudyIi58_HJ...@bt.com...
There is both. Centre pin goes straight to this tiny device. It is
designated R4. Off the back side of it, there is a small ceramic decoupler
to deck, and a series choke, L2, the back side of which trundles off to the
single pole on / off switch at the front edge of the board, as well as
having another little ceramic decoupler to deck. The return from the switch
comes all the way back to the rear of the board again, where it fetches up
at the arse end of a series protection diode, D3, marked 348A. The cathode
of this diode is then the main power distribution point into the 3v3
regulator etc. So the device that has failed is definitely some very low
value series element, and I'm still thinking resistor, as it is called "R4".
I too tried Googling without finding anything. The unit is needed for
Friday, so not finding anything definitive on what the device is, or its
value / type, I think I am going to stick with a low value fusible R. The
volts drop is very small across the 1 ohm that I hung in there. I might go
down to 0.47 ohms, just in case it draws enough to increase that drop under
some circumstances. Can't see anything that looks particularly
current-thirsty on the board, though.
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> As for the key shennanigans, the key contacts are probably operated by the
> hammers that the key moves, rather than the key itself. Up-ending the
> keyboard causes all these hammers to hang loose, probably close or even
> touching the contact strips, so you will get very unreliable results.
> The hammers give a realsitic impression of how a real piano feels to play,
> something a lot of pianists like.
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> Trouble is it makes the keyboard the weight of a small car.
Yes, I think you are probably right. The keys do have that mechanically
'weighted' feel of inertia, and it *is* the weight of a small car ... :-)
Arfa
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> Gareth.
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