trackspot beeping

Problem solved.

since, according the manual, it should be a problem of the p. switch (wheels are homing) I have replaced the IC between the p.switch and the bus.

Sorry to open up an old thread, but I'm having the same problem. What IC was it that needed to be replaced? (Location on the board/ IC number?)

Thanks a lot!

What I have replaced is IC6 or IC7, depending on the revision, a 74HC245, it is the busconnector for the personalityswitch and I believe it is located near this switch.
Before I have replace this IC I have checked the switch because it is possible that the switch itself is the problem. I have solved this problem a couple of time by just moving the dipswitches up and down.
I hope this will help you solving your problem.

Can I ask how you managed to replace the IC? Getting underneatht the PCB looks almost impossible! It looks like I'd have to desolder the XLR sockets to do that? The sockets have a plastic mounting on the outside which means you can't pull the PCB away from the bottom metal casing, and I can't remove the aluminium plate that is under the PCB because the dimming transisters have heat conducting glue attaching them?

Edit: As a last resort I'm tempted to snip the lead for that dip switch. I would, but I'm just wondering what the point in it is anyway?! I assume that it would be if you are monitoring certain aspects of the init process, but I haven't found any resources which explain what to monitor. I have an osciliscope and multimeter but not sure how I could use them without detailed specs?

Cheers

Removing the PCB in a trackspot is really easy, no desoldering neccessary. All you have to do to remove the xlr connectors is there is a little screw inside the connectors, use a flashlight to look inside. You have to turn the screw about 1/4 of a turn. There is one on both connectors. Then on the SCR's just undo the screw holding them down. Then remove the light shield between the lamp and circuit board, then remove all the silver screws holding the circuit board to the metal frame. Now you can slide the circuit board forward and lift it out.

Thanks - I now see the tiny screw on the XLR socket, (The male one anyway), it's the one that needs a flat screwdirver, right? Can't see it on the female one but I assume it's just a bit hard to see, and it's where one of the male pins would go?

Regarding unscrewing the dimmer transistors, I assume I'd need to apply some heat absorbing material when I reattach them?

Lastly, two questions - is there any easy way of testing that this is actually the problem before I go through all this hastle? (It is hastle, isn't it!?) Either by testing with some kind of external circuit that the wrong signal is getting through, or by faking the signal that the 74HC245 is giving out? I presume for the former, I'd need a kind of latch that samples the signal when the bus requests it, but for the latter I should be careful as I could mess up the 74HC245 worse than it already is, or even worse mess up whatever else is using the bus

Thanks again

I'd just swap it personally. Those are cheap, and most "real" electronic stores have them in stock. (remember back when radio shack used to sell stuff like this). I dont think it would be easy to reproduce the signals comming out into the bus, yet i do not know exactly, i have not looked at the spec sheet. I would first take the personality switch out of the circuit and meter that, anytime something is supposed to get 0V or 5V to ground but gets something weird instead, things act freaky.

Ok I'll give a go swapping the boards with another trackspot board first, (I have one where the board is ok but everything else is on its way out.

Then see how that works, I normally buy my electronics from maplin.

Do you think High End would give me the spec sheet for the PCB? Maybe I should ask!

they will give you the schematics, and with some math and some component spec sheets, you can figure out whats going on. www.highend.com/support/discontinued/trackspot.asp
Just look under schematics and choose which one based on what motor driver chips your trackspot has.

By the looks of the circuit diagram I have two options:

1) snip pin 1 of the switch, maybe it's stuck shorting the connection.
2) Snip pin 18 (output pin for the switch) of the 74HC245, assuming that the data line will float hight? Otherwise I'm going to have to get my hands dirty and desolder the chip and put in a new one...

I don't know much about the microprossessor at all - would its data lines automatically float high?

Thanks

i would desolder pin 1 of the switch, and just pick it up off the pcb and test it that way. Its much easier than cutting then if its not bad trying to fix or replacing the dip switches anyways.