Dead LedTriks

[biffklg]

I started this on a different post but decided it didnt belong there so I started on a seperate post. I have had my LedTriks up and running for about 2 months now. It started acting up a week ago by making several random led's come on which made the sequences almost un-readable. Now it will not run anything at all. It doesnt even blink or flash a single led. I have checked my power supply and that is fine and the power led on the pcb is on. I checked for continuity on the controller cable from my comuter to the pcb and that is fine also. I am not sure if there are some pins that I could hit with my multimeter to see if any of the chips are dead or not? I did notice one thing in the instructions that I might have made a boo boo on. It says that you have to tie the power supply ground into the computer port ground. I didnt do that I am unsure how. I just ran the 5V and ground from an extra disk power plug to the LedTriks pcb plugin. It worked just fine until a week ago... Could this have caused a serious problem? How do you hook the two together?

Thanks for any help.
Ken

[Ronp]

you only need a second ground if you dont use the control PCs power supply.so thats not the problem...

A. what chips alegro or mbi?

B. try running a vixen sequence on the triks you should get the top 2 lines flashing to the sequence.

when the triks sequence is running you shild be able to test the chips

I have put the ground from the multimeter on the ps ground then
put the pos. on pin 1 on the chips on the board and it shows 5v-5.2v
most every were else i get 2.2 v

[biffklg]

I tried running a standard sequence with the olsen 595 plugin and still got no responce from the screen.

I just tried probing everywhere on the pcb.

With a sequence running (ledtriks sequence) these are my results.

I, too, am getting 5.2 on pin 1 of the decoder chip and also pins 1 and 16 of all the drivers but am only getting about .2 v on most of the other pins on the decoder.

I used the allegro chips and it shows 3.6 on most of those pins and all of the cathode line outs at the rj45 jacks.

So it looks like it is firing, must be a problem with my cabling from the pcb to the screen. I keep the pcb in the house and ran 6 foot cat5 cables out to the screen. Everything is secure and has not moved, no obvious damage anywhere that I can see. Gonna do a continuity check on the cables in the morning...

[biffklg]

I have not been able to get around to testing my cables going from the PCB to the screen but I remembered something about when it died.

We had a computer problem (lighting computer died) and had to change things around some. I moved the lighting stuff (olsen 595's for the 4th of july show) to my computer and ran the show from my computer. Since I only had 1 port avalable we ran a cat5 extention up to Zane's computer to run the ledtriks. Problem there is I, was still powering the ledtriks pcb since it was fastened to a small shelf next to my computer, the olsens have their own power supply. There was no ground going from the power supply (my computer) to the computer port on zanes computer. Could this have fried something on the ledtriks PCB? Hopefully I can get this figured out soon, I love my ledtriks!
Thanks for any help.
Ken

[stempile]

biggklg - Did you ever determine what the issue was?

ms

[biffklg]

no I have not. I Have not had the time to check all those wires yet... ugg

[biffklg]

I did a change of the 4 driver chips this evening (I would have changed the decoder but I somehow ordered the wrong one.) Anyway, I was testing it after I changed the decoders and suddenly got a whiff of something hot and did some touching. It was the allegro in slot U3 it was hot to the touch but the other 2 where not. I am assuming that one is shot now and will have to be replaced. What could have caused that to get hot? I never did get any led's to flash, flicker or otherwise turn on during this test. Help please...

[P. Short]

My gues would be a short between one of the Allegro outputs and +5 (solder short maybe), or possible a shorted LED (less likely that this would blow the chip).

--

Phil

[biffklg]

OK, so I tried this today... To rule out a short in the led 'screen' I pulled all the cables off the PCB and plugged it in. Even with no sequence going and vixen not even running the U3 chip gets hot very quickly (15-20secs)... I looked over the soldering and I see no short anywhere and this was a working unit for about 2-3 months before it died. I just switched the allegro that was in U3 with the one in U1 and to my surprise the one that was in U3 but is now in U1 got hot but the other did not. I am assuming that it must be that the chip is shorted inside or something. What might have caused it? I will still be looking over the 'screen' for any problems and I have 6 more "sample" allegros coming... Thanks for any help in advance...

[biffklg]

WOOHOO!!!! IT'S ALIVE!!!!! I finally got around to changing the 3 allegros today and it works again. Obviously running the board without being grounded to the power supply or maybe the power plug in shorting caused them to go bad. Either way I am very happy to have my ledtriks back! I am in the process of re-doing the power plug in to make sure things never short out again, if thats what happened...
Thanks all!

[lytnin]

Biff, thats great news that you are back up and running.

I've just completed my board. I also made an 8x8 test panel, so I can double check I have all the LED orientations correct. I made a little test sequence just using those 64 LED's and was very happy. I disconnected everything and came back later to show the neighbour and no go.

The only thing I could think of was maybe a spike when I was reconnecting power to it. (Temporarily using some alligator clips) I haven't had a chance to check it out yet, but I'm going to be putting a switch in before I swap out the Allegro's & retest.

I don't know if this is something that may have happened in your setup. Just a thought so others can avoid the pitfalls if we can isolate a cause.

Anyone else had any problems, or found a cause :?:

Cheers