Repairing WS-1 after lightning

B

bwims

New Member
Hi, lightning killed my WS-1 and I've replaced all the visible ICs.

The only schematics that I have found are either the old irrelevant V1 from "sensors" or the one in Tim's Weather Toys book.

However, neither account for the big black epoxy blob on the board. Since I don't seem to be getting sensible values from the ADC, I suspect there may be a chip under there that is not on the schematic.

Can anyone help here?

Thanks,

Brian Williams
 
I don't know what is under the black epoxy but I will try to find out for you. Not sure if it will be much help though because I'm not sure how you would remove the chip under the epoxy without damaging the board.

Eric
 
ericvic said:
I don't know what is under the black epoxy but I will try to find out for you. Not sure if it will be much help though because I'm not sure how you would remove the chip under the epoxy without damaging the board.

Eric
Click to expand...

Thanks Eric,

well, if nothing else, I'd like to know if I'm wasting my time trying to repair it, and I'd also like to know what the real schematic is. I guess the one in Tim's book is based on the AAG schematic that used to be on their website when it was useful, before it became the horrendously cut down one they have now.

I don't suppose hobby boards stock replacement pcbs do they?

Brian
 
ericvic said:
bwims said:
I don't suppose hobby boards stock replacement pcbs do they?
Click to expand...

Nope, AAG would not let us stock repair parts.

Eric
Click to expand...

Hmm. That was big of them, especially since they don't seem to have squat on their web site now!

Re: the epoxy blob, it looks like it is only covering jumpers anyway. see

deanostoybox DOT com - weather - hardware - AAGv3compID DOT html

where 'hyphen' = slash (Can't post links yet)

I don't know how he figured it out... maybe he scratched off a dead board.

Anyway. My board was frazzled and I've replaced all the chips, but the situation is that when I hold a magnet over the reed switches, most of the time I get 0.3 or 0.4 volts and only a couple of times do I get 2.5v

Any idea what I should check? Replace the capacitor perhaps?

Very grateful for any help!

Thanks

Brian
 
Correction to last: OneWireLister reports 0v when no switches are closed (should be 5v) 2.4 when a switch goes to ground and 0.03 when it goes through the resistor to ground.

Thanks

Brian
 
one last thing: is there a problem with onewirelister? I have checked the voltages at the pins of the ds2450 and the multimeter shows 5v when the switches are open (as it should) but OOL displays 0, 2.5 when OOL displays 2.5 and 0.00 when OOL displays 0.03. This is weird!

Brian
 
Eric:

I think I have partially solved my problem. It seems that there is some kind of initalisation sequence that onewireviewer does not do for the DS2450. Until I run simpleweather, strange voltages show. Afterwards, OWV shows the correct voltages. Bug in OWV?

Thanks for reading all this stuff.

Brian
 
Final update.

It seems you can change the ADC configuration (by hand, not cut and paste!)

From

08 8C 08 8C 08 8C 08 8C

To

00 0D 00 0D 00 0D 00 0D

and it works.

Sorry to inflict a learning experience on you!

All the best

Brian
 
bwims said:
Final update.

It seems you can change the ADC configuration (by hand, not cut and paste!)

From

08 8C 08 8C 08 8C 08 8C

To

00 0D 00 0D 00 0D 00 0D

and it works.

Sorry to inflict a learning experience on you!

All the best

Brian
Click to expand...

Yes the default state of the DS2450 is for 2.5v max input. You have to change the configuration for 5.12v input.

Eric
 
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