Troubleshooting

[Tony]

IMPORTANT: IF YOU ARE HAVING PROBLEMS PLEASE CONTACT ME DIRECTLY BY EMAIL.

Help and advice to get it running.

PCB track layouts TOP:



PCB track layouts BOTTOM:



v1,11a PCB track layouts TOP:



v1.11a PCB track layouts BOTTOM:

[sonicwarhawk]

Ok so heres the deal. my thermo is all together but..... no data is displayed. i can switch modes and the nixies will display k/f/c/%h. but the others nothing, no led. but if i put it in scramble i belive it to be the mode, it will scroll back and forth across the other 3 nixies. no data mind you but lust light up the led and almost like it lights up the cathode in them very quickly? what did i do wrong?

[sonicwarhawk]

Also it will not power on without something between r28. no mention of a resistor in the instructions.

[Tony]

No data is exactly what the problem is, it's not reading anything from the sensors. Check the surface mounted IC is the right way round and there are no bridges, then the data lines from there to the PIC, watch for a bridge at the top end of R11 and R12 and between the centre pins of the DHT11 sensor.

I've added the bit about R28 to the instructions, not sure how I missed that.

[sonicwarhawk]

Tony, i double checked and triple checked. installed the r28.No bridging. still no data. could i have a bad sensor?

[Tony]

As it uses data from both sensors an internal short in one could prevent the other from working. Remove the SM IC, if it still won't display anything check with a meter for a short between the middle pins of the DHT11 and from those to 5V/ground. If that's OK you probably do have a dead DHT11.

[sonicwarhawk]

Tony. looks like a dead dht11. bummer

[Tony]

The fastest way to replace it will probably be to buy one on ebay from a US seller and I'll refund the cost, it should only be a couple of $.

[sonicwarhawk]

No worries Tony, i got one coming from amazon. be here tuesday. thanks for your help!

[adminbear]

Is there a schematic of the Nixie thermometer avalable??