Testing JRK to Determine Damage

I have a JRK 12x12 and I am trying to determine if it is useable.

History: I had soldered pins in the -, + and FB positions. While trying to set up my lever position, I released the "magic smoke" from my pot and after looking things over, the pins on the JRK were not soldered well enough and the wirer fell against each other.

My first action was to wire a new pot and check the JRK with my multimeter. Unfortunately, although the pot/multimeter showed voltage changes, the JRK would not "learn"/see the changes.

Tonight, I soldered new pins in the other -, + and AUX positions. After wiring a pot, the JRK is behaving the same way - not seeing/"learning" the change in voltage. I checked the solder points on the JRK and the points are indeed registering different voltages.

The JRK utility still recognizes the JRK when I plug it in and the "learn" function does register a voltage, the problem is it showing the same value for the maximum and minimum (and it is different than the default).

So, after that long winded story. Should I schedule a JRK funeral or is there a different way I can check the JRK? I hate to throw $100 in the garbage.

Thanks,
Steve

Not sounding good, I guess it was working OK before the smoke was released?

@SeatTime - I am assuming it was working, but I hadn't actually ran a game. But, I think it was responding fine and the issue happened while I was adjusting the PID values. I agree, it does not sound good. In the back of my mind, I was hoping that a fried JRK wouldn't even be recognized by the computer so perhaps this 1 could be brought back to life. Even visually, it looks good.

I have a new one ordered. Now I wait. Luckily, the only thing I have to wait for is traction loss.

Steve

@eaorobbie may be able to help. I think he has smoked a few JRKS in his time

remember to tell the original supplier and they may replace is at 50% off if you ask nicely.

Send the email to Pololu with description what happened and some photos if necessary. They could give you an accurate answer what to do and if it is recoverable.

I've had a problem with one of the JRK's when I've accidentally scratched one of the small resistors on the board with a screwdriver. I didn't want to turn it on just to prevent any other damages or smoke so I've sent an email to them with photos of resistor's position, they told me that it was not big problem and everything will work just fine because it was connected to AUX pin anyway and for simulator we didn't use that pin at all.

Ok there may be one or two tests you can do.

The Aux pin can be used to run our simulators , mine is actually connected that way from habit.

What this allows you to do is to set a error catch with in the Jrk if the pot fails for any reason, as in a feedback disconnect. And if triggered shuts down the Jrk.

Ok to invoke the use of this pin you must set the checkbox in the Feed Back tab of the Jrk Software.
Then I would unplug(reset) the Jrk and then re open it, then reset the feedback range to Max , and apply the settings then move the pot to see if the line moves in the graph. If not you might have killed the Feedback pin on PIC (the Jrks microcontroller).

Thinking out loud and please be careful doing in this , use a meter and check if 5v is present on the Aux or 5V pin. If it is then use a jumper wire and touch one of them to the FB pin the scalefeedback value should jump to 4095 and if you touch GND to the FB pin it should drop to 0.
But please be careful doing this.

Lastly log onto the Pololu forum and ask them a question , I did this and now it doesn't work, any chance of help or help in replacing the item. Even an email can help too, they're support guys are really good to deal with, Us Simmers do have a good reputation there.

@eaorobbie - I took your advice about the Pololu forum, but I am wondering/hoping the issue is somehow on my end. I had ordered a replacement JRK and received it today. I was triple careful while soldering the pins and wrapped all connections with tape. The new JRK is doing the exact same thing. I can measure voltage changes with my meter at the pot posts and the JRK pins, but the "learned" max and min readings are the exact same! UGH! If I hadn't already setup 2 JRK's successfully, I would think I was missing something obvious.

I will be sure to report back here what I find out from Pololu tech support.

Steve

Try a different USB port ?

Before setting min and max.
Click Reset to Full Range , and then Apply settings to device.
Now physically move the pot and the red line in the graph should follow the pot.

@eaorobbie - I am not sure if you are just a JRK ninja, but the Pololu support email said GRD, +5V and AUX is not a valid configuration.

After the fact, I will try to summarize what I think happened on my end and hopefully it helps others down the road.

As described above, my first attempt was with the GRD, +5V and FB positions. After my wires touched and I smoked my pot, I tried a new pot on the same 3 pins - problem with "learning" started.

I then soldered 3 new pins in the other GRD, +5V and AUX positions. Same "learning" problem.

Ordered a new JRK and soldered pins at GRD, +5V and AUX positions. You guessed it, "learning" problem.

After receiving an email from Pololu support politely telling me I must be on crack, I soldered a new pin on the FB on the new JRK. DING DING DING! Winner winner chicken dinner.

That got me thinking about the JRK that started this mess. I left the 2 pins in the GRD and +5V positions on the AUX side (these were NOT used when I smoked the pot) and I soldered a pin back into the FB position. DING DING DING! It looks like the problem was with the GRD and/or +5V positions even though my meter was indeed reading good numbers. Either way, it looks like I have an extra JRK in stock!

So, I am not sure what kind of ninja power @eaorobbie is using that allows him to use the AUX pin instead of the FB pin, but it did not work for me.

This turned out to be easy, you were using the wrong pins (that is why I asked if it was originally working). Aux or 5V pin for power and always FB for centre of pot and of course Ground to close out the circuit. Re read @eaorobbie's post - he never said to use Aux instead of FB?. Good although to see it sorted.

@SeatTime - I must have misread a previous thread. I was thinking the 2 sets of pins could be interchanged. Believe me, I am very happy it was a screw up on my part. I now have an extra JRK in case I need it.

agreed, what ever @eaorobbie is smoking, I want some. I just wired up according to this and never had a problem

Thanks he doesn't read the documents provided by pololu , the Aux pin can be used instead of the 5v pin so that you can set the feedback disconnect error that can be set in the Jrk. Sorry if I confused you @CoachKalk was not my intensions. Thanks @bsft for suppling my wiring pic too.