Ice Tube Clock showing dddddd, not 888888

[dxmaniac]

Hi all,

I received my Ice Tube Clock yesterday and went right on building it. As far as I can tell, it went rather smoothly(but I shorted the transistor Q3 while clipping the wires, it gave off a spark), the test measurings during the build were ok, but not the finished clock doesn't seem to work properly. I've already replaced that transistor, just to be sure, but that didn't do the trick..

The display is showing the dot in the upper left corner, the minus on the left and every digit is showing "d", but not the time or anything else.. Also not when I press any buttons. It beeps once when I plug it in, the display shows its Ds and after a while the display fades out with quite a lot of beeps..

I've made a video of this:
http://www.youtube.com/watch?v=hSuQI7XfgDw

Help, please?

Regards,
Andre

[madworm_de]

How can it spark when clipping the leads ?

Unless... (1 minute of reverent silence) ... the power was still connected. Q3 is an PNP high side switch for the logic side of the VFD chip. You may have shorted the base to some unfavourable voltage and thereby blown the VFDPWR pin (or more) on the ATmega. Do some more tests. Does the ATmega still work 100% ?

Some general rules when tampering with electrical things:

1. turn it off
2. make sure it stays turned off
3. make sure all voltages read ZERO (capacitors discharged...)

There are some more life saving rules, but as I do hope you will never ever touch mains lines or even worse stuff, these 3 should suffice for now. The next time you think "whoops", you may be dead.

- run down the curtain
- meeting the maker
- pushing up daisies
- visiting the eternal hunting grounds
- rotting in your grave
- being eaten by worms

Oh, and if you should happen to see a black hooded skeleton sitting on a chair reading a book while you're poking at stuff with a screw driver, you may be having a Near Death Experience. Time to think about your next move.

[dxmaniac]

How can it spark when clipping the leads ?

Unless... (1 minute of reverent silence) ... the power was still connected. Q3 is an NPN high side switch for the logic side of the VFD chip. You may have shorted the base to some unfavourable voltage and thereby blown the VFDPWR pin (or more) on the ATmega. Do some more tests. Does the ATmega still work 100% ?

Some general rules when tampering with electrical things:
...
3. make sure all voltages read ZERO (capacitors discharged...)

That last point is most probably what happened.. I have handled 12V/40A circuits before on my r/c models, but in there, the power is gone as soon as I remove the plug. Is there any way I can test the ATmega without a programmer for it or a "real" serial port?

[adafruit]

oh dear it does sound like something got a bit damaged. try removing the VFD chip and tube and perform the voltage tests. leave it plugged in for a half hour and perform the tests then to verify it -still- works

[dxmaniac]

oh dear it does sound like something got a bit damaged. try removing the VFD chip and tube and perform the voltage tests. leave it plugged in for a half hour and perform the tests then to verify it -still- works

Apart from the strange display, everything seems to work fine, I've found some time to make the tests..

I'm using a 9V power supply to run the clock.. When I have the clock with the buttons and power plug facing AWAY from me, I get 9V on the front pin of the 7805 and 5V on the rear one. And I'm getting 56.7V on the right(striped) side of the diode..

After waiting half an hour, I still get the same values..

Oh and the fuse is not hot or warm or anything.. read something about hot fuses, somewhere in the forum..

[adafruit]

turn it off, insert the VFD chip and repeat the tests

[dxmaniac]

turn it off, insert the VFD chip and repeat the tests

I think you've hit something there

When I insert the Maxim-IC, again with the buttons and power jack facing away from me, on the 7805 I get about 7V on the pin facing towards me(at 9V input current) and 5V on the rear pin.

On the diode, I only get a meager 6.5V as opposed to about 58V without the IC.

[adafruit]

do you have the socket/chip in the right way?

[dxmaniac]

do you have the socket/chip in the right way?

The socket is in the right way.. the "cut off" corner is on the bottom left corner when viewed from the top.

And there's a bevel on the chip, it's pointing to the left..

http://blogsberg.sparced.org/uploads/dx ... g_0526.jpg

[alishl06]

It looks like you may have mounted both the connector and the Tube on the wrong side of the PC board. I do not see the silk screen writing that shows where the three No connects go or the other markings (like UP).

[alishl06]

The Tube looks odd. It looks like there are only two NC's inside the tube instead of three (or none).

[dxmaniac]

It looks like you may have mounted both the connector and the Tube on the wrong side of the PC board. I do not see the silk screen writing that shows where the three No connects go or the other markings (like UP).

The Tube looks odd. It looks like there are only two NC's inside the tube instead of three (or none).

That's only because of the angle the picture was taken from.. The tube does have 3 non-connected pins and they're mounted on the PCB as shown in the assembly instructions:



The soldering looks better on the other side, all nice and clean, so I don't think that it's a problem that not all wires are covered in it on the side shown in this picture..

[adafruit]

could be the VFD chip is smashed, what happened is that the 56V got shorted to the VCC pin (next one over) and fried the bugger. you can email support@adafruit to get a replacement - we suggest also getting a replacement ice tube processor chip since it may also have been fried at the same time

[dxmaniac]

could be the VFD chip is smashed, what happened is that the 56V got shorted to the VCC pin (next one over) and fried the bugger. you can email support@adafruit to get a replacement - we suggest also getting a replacement ice tube processor chip since it may also have been fried at the same time

Ok, thanks for your help..

At least most of the kit seems to be in working order.. getting only two chips through customs to Germany will probably take a lot less time than the whole kit which went a good bit above the limit where it doesn't have to get customs clearance

[dxmaniac]

Yesterday my replacement VFD driver and ATmega ICs have arrived and now I have a perfectly working ice tube clock.. I've even been wakened by it this morning Happy happy joy joy

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