Rigol DS1052E rotary encoder repair

[R-1125F]

I picked up a Rigol DS1052E that has a problem with all of the rotary encoders.  I know there has been a lot of discussion about this problem on EEVBLOG.  It seems unlikely to me that all of the rotary encoders would have gone bad.  Is this really happening, or is there some other problem? 

Also, I tried to downgrade the firmware from the latest, but this does not work.   Has anyone been able to do this?

[I4E]

downloading the firmware might be the USB stick you are using if you are trying to put it on the unit. You might want to try a cruzer brand stick.

Regarding the Rotary encoders. Have you tried contacting Rigol USA direct? They might still offer you some assistance or answer the questions you have.

Hope that helps. Have a fantastic day!

Sincerely
Instruments 4 Engineers Ltd
Authorized Rigol Distributor-UK

[R-1125F]

Thanks for the reply.   The firmware install went fine but it did not change the issue.   The other question I had was if there was a way to rollback the firmware from the latest version. 

I did some more research on the rotary encoder problem.   I think I need to replace them all.  Fortunately, they are all dirt cheap.   There were a number of different types and brands suggested, but I settled on the Bourns PEC12R series.   I think these will work. 

[I4E]

HI there.

In theory I suppose if you were able to get an old copy of the firmware you could do this but I have never tried this.. so can't say for sure about the outcome.

[R-1125F]

I tried that.  It won't take an earlier version.  There must be some way around this.   Anybody been able to go back to an earlier version?

[wasedadoc]

I tried that.  It won't take an earlier version.  There must be some way around this.   Anybody been able to go back to an earlier version?

I don't know if it will work for the DS1052E but the post at https://www.eevblog.com/forum/testgear/new-rigol-ds1054z-oscilloscope/msg3613778/#msg3613778 has information on downgrading the firmware of DS1000Z series 'scopes. 

[maybepanic]

Mine probably only had one or two encoders that acted up but that made it utterly unusable. Random button presses, all encoders not reacting to input at all or in an erratic way. Then suddenly it would only display white flashing lines after the boot up screen. No idea how that can happen. The constant none sense from the encoders maybe caused it to write foobar to the ram during boot? Idk. Replaced all encoders for a couple of bucks and it works well again.

[R-1125F]

I got mine working today.   All of the encoders are multiplexed.  One of them, the horizontal as it turned out, was putting out some garbage and messed them all up.  They are so cheap that I replaced all six.   I used Bourns PEC12R-4120F-S0012 for the horizontal and vertical controls and PEC12R-4020F-S0024 for the other four. These are a perfect fit.

A post on a Swedish forum was a big help in understanding the problem.  https://elektronikforumet-com.translate.goog/forum/viewtopic.php?t=99189&_x_tr_sl=sv&_x_tr_tl=en&_x_tr_hl=en&_x_tr_pto=sc

[R-1125F]

The noise from the bad encoder could have interrupted the boot process.

[cf4044]

The encoders on my DS1102E are all a bit dodgy but still work well enough for it to be just a major annoyance but not enough to make it unusable.

However having said that a few years ago they had suddenly become worse to the point of almost not working at all and even the buttons were very erratic, like pressing one key and resulting in the action another key should cause. After tolerating this for some weeks the display failed - it became some pattern of lines like broken TVs sometimes show.

I opened it up to attempt a repair and it became immediately obvious what was wrong - a ribbon cable was partially removed from its socket.  I don't quite remember which one it was as it was some years ago but probably the one that links the main PCB to the front panel. In any case I put the ribbon cable back in its place and secured it with tape or glue or something because it seemed very loose and would have come off again.

Since then it has worked fine apart from the slightly erratic encoders just like it was before the major failure.

 The worst are the two I need most, the horizontal position and the general purpose knob. For them to work properly I have to turn them very slowly otherwise they go randomly backwards and forwards.

I don't think the ribbon cable has anything to do with the current issue with the encoders but it almost certainly was the cause when they had failed almost completely before finally the whole thing had stopped working.

[R-1125F]

In my case I ordered all six encoders.  They were very cheap, about $1.50 US each.  Keep in mind that the encoders are multiplexed, so one bad one may affect all.  I wanted to find out which one was causing the problem.  To do that, I replaced one with a new one and there was still a problem.  I removed the next one tried the controls without installed and the problem still existed.  I replace that one and used the same process and eventually found that the bad one was the channel 1 vertical controlled.  All of the encoders cost me about $9 US plus shipping of about $8 US.  It was a cheap fix. 

For your ribbon cable; what is the condition of the connectors?  I have not seen one just come loose unless it was broken or not latched properly.

[cf4044]

In my case I ordered all .....
For your ribbon cable; what is the condition of the connectors?  I have not seen one just come loose unless it was broken or not latched properly.

Unfortunately my memory is not too good. It's been some years ago but I do remember concluding that the connector was broken or faulty in some way. I think it was one of those where the 'plug' is just the end of a flat ribbon cable, the sort that's like a printed circuit on a thin transparent plastic and the socket has a locking clamp that is pushed down to lock in the 'plug' but the clamp was not doing anything when I pushed it down - the ribbon cable remained loose.  I must admit though it's quite a while ago and I could be confusing it with something else I repaired since then.

[R-1125F]

It is easy to get the flexible cable installed incorrectly.  Both sides of the latch must be lifted and the cable inserted completely, then push the latch down.  If this is the LCD cable you are talking about, check to see if the connecting end is damaged.  If the connector or cable is damaged it should be replaced.   

I just checked the prices for encoders on Mouser in Europe and they are about the same price as in the US.  It is very cheap to replace them all.

[Atlan]

It was enough to disassemble the original encoder, remove the grease and put it back together.

[R-1125F]

The cost of the encoder is so cheap that it makes sense to replace, not repair.  Unless you can't wait, that is.