Xpantastic!

----- Original Message ----- 
From: "James R. Coplin" <james@...>
To: <xpantastic@yahoogroups.com>
Sent: Thursday, January 27, 2011 4:37 AM
Subject: [xpantastic] Replacement Encoders Found!


> Rejoice! Rejoice! Rejoice!
>
> I have found an extremely suitable encoder for replacing cranky/dead ones 
> on
> the Xpander.  They are relatively new from Bourns.  The part number you 
> want
> is PEC09-2325K-N0015.  Digikey and Mouser have them. They are 30 detent, 
> 30
> pulses per rotation.  Rather than D shafts they have the old style knurled
> round shaft.  The locking collets fit perfectly.  Unlike most encoders,
> these have a nice strong detent - not as heavy as the Xpander but solid 
> and
> obvious.  They work a peach.  The best part is they are around $2.30 in
> quantity 1.  Buy enough for 3 spare sets and you are set for life.  There
> are a couple of drawbacks, none of them major or deal breakers.
>
> First, the encoder shaft is long.  The part comes with shorter shafts but 
> I
> can't find anyone stocking them.  I used a couple of washers on the bottom
> side of the encoder to shim it away from the PCB to the correct height.
>
> Secondly, they are small in diameter so you will need to hold them while 
> you
> tighten them in place to keep them centered.  You could make some kind of 
> a
> spacer but I didn't bother.
>
> Thirdly, the encoders are only available with the through hole connection
> and not solder lugs so you have a little delicate soldering to do.
>
> Forth, the housing has a positioning tab you will need to cut off with a
> pair of snips so it sits flat on the PCB.
>
> Lastly, the housing is much smaller than the original encoders so will
> either need to solder on extensions to the existing connections or just
> replace them with new longer wire.  Which is the correct way to go about 
> it.
>
>
> James R. Coplin
>
>