Cobra Board

[Bob]

I've been trying to program my 5V programmable lights and running into issues.

Not sure if it's coding yet but i have the Cobra Board completely disconnected and on the bench.

The first thing I notice is the blue lights for the A, B and C Connectors are solid.

Not sure how that is with nothing connected

second thing is even odder. I tested for continuity between the VLED and the Ground on both the J11 and J12 terminals. Surprisingly there was which to me sounds like a problem.

I then checked for continuity  between the VLED and the Ground on the J14 and J10 terminals. No continuity, which is what I would expect.

After a while, I checked again and then I had no continuity on the J11 & J12  connector but continuity on the J14 & and J10 Connectors.

Long story, short but I 've now noticed the continuity between the VLED and GND posts goes back and forth. One minute I have it on the J11 & J12 connectors then i have it on the J10 & J14 connectors. I thought it was my meter but it's not.

 

Is this normal???

 

ganJ1 

  .os hinkg  right out of thge mach 

[cobra18t]

Can you share a picture of your test setup?

[Bob]

there is no test setup. It's just a board on a table with an Ohm meter

[Thomas Fulenwider]

You said the lights were on for banks A, B, C. Maybe just a residual charge from the power filter capacitors? If they are dim, that is normal. If they are bright and it continues that way without being connected to anything, you have discovered a form of cold fusion and we should talk offline.

Checking continuity will also slowly charge those capacitors.

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[Bob]

lol

they are dim now. board has been unplugged for a couple of hours.

I'm still getting continuity (now) between the VLED and the Ground pins on the J14 and J10 terminals. Is this normal?

[Bob]

Now (15 minutes?) it shows c ontinuity between the VLED and the Ground on both the J11 and J12 terminals.

No longer continuity  between the VLED and the Ground on both the J10 and J14 terminals.

Is this normal?

[Bob]

Ok I found out something else.

If I hold my probes on the the 2 pins that have continuity. the continuity shows initially but breaks after about 8 seconds breaks. 

that's when it switches to the other 2 terminals. I can get it to go back and forth 

[Bob]

I discharged the capacitors (the were hold around 2 1/2V each).

Blue Lights are out but the trick with continuity still remains 

[cobra18t]

Uncharged capacitors act like shorts, so they will show up on a continuity test and then the continuity will go away as they start to charge. It sounds like things are normal on your board.