XV-3080 Encoder Replacement ?

Forum for JD, JV, XP and XV synthesizers from 1990's
ColinD
Posts: 17
Joined: 20:31, 17 March 2017

XV-3080 Encoder Replacement ?

Post by ColinD »

Hi guys,

Not sure if this is covered by the other post regarding the 5080 encoder ?

My encoder is a little ratty.... it's encoding correctly but the push / pull mechanism doesn't seem to 'feel' right to give small increments or large ones.... also the push buttom is very twitchy !!

The encoder board has 4 wires, so not sure how this works handling the two ranges and the push button !!!

An encoder has an A and B Signal... so that's two wires !! Plus a switch - another wire and a common 5v or ground.... so that's your 4 wires !!! SO how does the push pull action work then ???

edit.... There might be a resistor network in the switch involved ?? - so maybe the switch would give say 2.5 v out when in the other range or 0v for a press ???? I should maybe have a poke around and see !!
encoder1.JPG
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encoder2.JPG
encoder2.JPG (89.39 KiB) Viewed 3828 times
I can probably replace this with another type to just give single counts and the push button (no large counts via push pull) but you can use shift and inc to skip anyway for that !!

So.... Any suggestions on a part that might fit ?? - I don't need the two ranges and happy with single counts and a button.

I can easily knock up a new carrier PCB cheaply to suit if I know the ins and out of the old part , so could have a drop in low cost replacement made available if any demand ??

With further thoughts ,a little reverse engineering and a low cost micro controller I may be able to do something like a short press to change the range of the dial (or just increment by 10 ?), and a Longer press (maybe a second) to act as the origonal button ??? So a sneaky work around for the obsolete encoder !! ;-) - However you might need to add an extra wire (or possibly 2) to supply power to it !!

Cheers, Col

I'm guessing something like this would do the job ??
http://uk.rs-online.com/web/p/mechanica ... s/7295592/

But looking again... looks like the encoder needs to be mounted with a locking nut, so back to the start again !!
rcraven
Posts: 629
Joined: 14:36, 9 September 2007
Location: Melbourne Australia

Re: XV-3080 Encoder Replacement ?

Post by rcraven »

Hi Colin
you can often fix lots of erratic encoder problems by spraying/dripping some electrical contact cleaner down the shaft and in through the threaded housing. Then work the contacts a bit by pushing and spinning the shaft.

The solvent will quickly evaporate leaving clean switch contacts.

Doesn't always solve all the problems, but it would be the first place I would start.

All the best
Royce
ColinD
Posts: 17
Joined: 20:31, 17 March 2017

Re: XV-3080 Encoder Replacement ?

Post by ColinD »

HI Royce,

The encoder works fine as an encoder but the 'low / high' gear change doesn't feel right ( I was expecting it to feel more more solid / positive) and the push button is too sensitive, so I think its more of a mechanical issue and its worn internally.

I'm going to investigate how it works and come up with some kind of viable replacement that feels right to me, so will post back how I get on.

Have got a couple of encoders on order (they are only a couple of dollars each) to try out and see if I can make them fit. This might require a new carrier pcb, but these are low cost to have manufactured now days and are typically a couple of dollars each when you have 10 made up.

The only issue I can foresee is either throwing the 'high gear' option away (which is a nice to have) or come up with a nice work around if I can work out how this extra signal operates. EDIT... IF YOU HOLD SHIFT, it goes up in 10's anyway - so probably not an issue !!

The encoder itself and the push button should be straight forward.

Regards, Col
ColinD
Posts: 17
Joined: 20:31, 17 March 2017

Re: XV-3080 Encoder Replacement ?

Post by ColinD »

Looking at this... the pcb looks identical to the one shown on the 5080 encoder genesis92 thread.... although its got a different part number !!
both.JPG
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My hunch is that there is a resistor or a diode inside the high/low switch and button switch to combine both functions.... lets see.....

Anyway.... watch this space , I'll see what I can come up with and will go quiet now for a couple of weeks at the very least !! ;-)

Regards, Col
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genesis92
Posts: 22
Joined: 11:01, 9 January 2017
Location: Near Paris
Contact:

Re: XV-3080 Encoder Replacement ?

Post by genesis92 »

The encoder seems to be the same as the one used on the XV5080.
ColinD
Posts: 17
Joined: 20:31, 17 March 2017

Re: XV-3080 Encoder Replacement ?

Post by ColinD »

Yes, It appears that I was wrong with the high / low push pull position 2 position encoder!! - The encoder should go up in 10's when its button is pushed in and that's it, nothing fancy its just a pretty standard component !!

That shows you mine is pretty worn then and the knob must also be a loose fit too !!

Cheers, Col
ColinD
Posts: 17
Joined: 20:31, 17 March 2017

Re: XV-3080 Encoder Replacement ?

Post by ColinD »

Little update.....

Have ordered some nice long life Encoders which should fit perfectly and also have the key pin/tag to stop it rotating in the panel (although its only 24 Pulses Per Rev)

I have tonight designed a nice new drop in PCB which I'll have made up in China.
ENCODER_PCB.JPG
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I'll let you know how I get on , hopefully I've got the design right and the new encoder should fit exactly in place , you just have to solder the 4 way connector in place.

I'll have a limited few spares available assembled at a reasonable low cost price if anyone would like one sending out :-)

Cheers, Col
ColinD
Posts: 17
Joined: 20:31, 17 March 2017

Re: XV-3080 Encoder Replacement ?

Post by ColinD »

PCB Panel put together and will be sending this off tonight to have manufactured.. and also have a backup plan if I have got the A + B channels mixed up (the ones with the # in the corner) .... So in total I'll have 60 pcb's made up for the price of 10 (which is the minimum order !!) if I've done my math right !!

I only need one , but like to do a decent job and hope these will come in useful fingers crossed if I've got it right !!!

Looks sweet anyway :-)
roland_encoder.JPG
roland_encoder.JPG (382.28 KiB) Viewed 3773 times
Cheers, Col
synthman
Posts: 111
Joined: 12:46, 10 August 2012
Location: London UK.

Re: XV-3080 Encoder Replacement ?

Post by synthman »

I'm interested in this. I have a xv 3080 and although it's encoder is fine it might be good to have a spare ready to fit if needed later on. Keep me updated please.
ColinD
Posts: 17
Joined: 20:31, 17 March 2017

Re: XV-3080 Encoder Replacement ?

Post by ColinD »

I've had some pcb's made up.... These use a 24 way encoder and work well :-) - The detent is a little softer than the original and the push button is nice and clicky. The thread is the same size and also has the mounting nipple so the thing sits solidly and won't move about or work loose.

They fit nicely, however.... there are two small issues.

First is that the connector has a slightly different pitch so you have to bend the pins slightly so it doesn't sit quite flush. If you are skilled enough to disassemble the unit in the first place and de-solder the connector, this won't pose any major issues to you !!

Second is that the knob seems to sit a little deeper in the panel due to the cutout on the encoder being slighly different (you can insert a small 'spacer' inside the knob to taste if you wish but most people won't even notice).

I have 9 of these 'warts and all' as above available for sale to help cover my costs for the custom pcb's , encoders and import duty. These are priced at £20 each assembled plus postage (£5 UK and £10 USA) - I hope you all find this is reasonable :-)

Please email me with your address if you wish to buy one of these.... colin.w.davies (who lives 'at') btopenworld (d-o-t) com

Thanks, Regards, Colin
encoder_fit.JPG
encoder_fit.JPG (65.26 KiB) Viewed 3722 times
Pins above on connector had to be bent out slightly to fit.
encoder_fit2.JPG
encoder_fit2.JPG (126.49 KiB) Viewed 3722 times
Fits nice and slightly smaller than original.
encoder_fit3.JPG
encoder_fit3.JPG (59.74 KiB) Viewed 3722 times
Wiring fits and not 'too' tight.
encoder_fit4.JPG
encoder_fit4.JPG (61.94 KiB) Viewed 3722 times
Plenty of space / clearance to metalwork behind.
encoder_fit5.JPG
encoder_fit5.JPG (88.42 KiB) Viewed 3722 times
Shows the slight pitch difference for the connector.
ColinD
Posts: 17
Joined: 20:31, 17 March 2017

Re: XV-3080 Encoder Replacement ?

Post by ColinD »

encoder_fit6.JPG
encoder_fit6.JPG (80.89 KiB) Viewed 3722 times
Shows different 'shaft' cut out, which makes the knob sit a little lower.
encoder_fit7.JPG
encoder_fit7.JPG (76.7 KiB) Viewed 3722 times
Full Module.
synthman
Posts: 111
Joined: 12:46, 10 August 2012
Location: London UK.

Re: XV-3080 Encoder Replacement ?

Post by synthman »

Just to recap. These are supplied "ready assembled ?
ColinD
Posts: 17
Joined: 20:31, 17 March 2017

Re: XV-3080 Encoder Replacement ?

Post by ColinD »

synthman wrote:Just to recap. These are supplied "ready assembled ?
Yes, the PCB will be supplied with the encoder fitted / soldered in place, so ready assembled... Its just a case of de-soldering the connector off the original pcb and soldering it to the new module (and bending the pins slightly to fit).

The encoders are also rated for 100K Turns (and not 30K like many others), so you should never need to replace this again unless you are a really heavy user !!

You could also just snip the wires off if you wished to avoid de-soldering , but make sure you mark them first 1 to 4 !!! - It really is just a straight swap over job.

There are a few screws to remove, and the nut on the encoder but should not take more than an half an hour or so if you have the tools to hand.

The PCB's are 'good quality' (not home made ones) , have plated through holes with nice solder resist and are very robust. Most probably better than the originals !!

Hope this makes sense, Cheers , Col
synthman
Posts: 111
Joined: 12:46, 10 August 2012
Location: London UK.

Re: XV-3080 Encoder Replacement ?

Post by synthman »

Yes that makes complete sense just checking. Can you put one aside for me. Don't get paid now untill next month. Bit skint this month. :-(
ColinD
Posts: 17
Joined: 20:31, 17 March 2017

Re: XV-3080 Encoder Replacement ?

Post by ColinD »

synthman wrote:Yes that makes complete sense just checking. Can you put one aside for me. Don't get paid now untill next month. Bit skint this month. :-(
Send me your address and I'll get it sorted for you ;-)
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