I purchased a gadget, a current load, ammeter and voltmeter, here:
Unfortunately the voltmeter is about 13% wrong, hooked up to a 10.000 V source it reads 11.330 V. After lengthy exchanges of emails with the supplier, and measuring the voltage at various points, and the values of various resistors, they are asking me to desolder a couple of SMD chips and test the voltage.
Do you think this is going too far? I have never desoldered a SMD chip before, although I recently got a SMD hot air rework station. Removing two chips from a fairly crowded board, and then putting them back, for a novice, sounds like a dodgy exercise. If the board was my own, well it would be my fault. But this is a purchased board that is supposed to work.
Do you think it is time to call it a day, and return it for repair? Or am I supposed to be able to fix this sort of stuff on my own?
I would not even attmept it without a e-mail from them that they have adivised you to try it, and their warranty will not be voided!
If it is only a several pin device (up to 4-6 pins), pobably not too unreasonable, however if it is more then that, I shudder to think about it without proper equipment.
Is the cost of shipping a large factor?
My personal preference if I was in your situation would be for them to send a replacement. Besides, once you have determined what is wrong, they still have to send replacement parts to be soldered back on. You would always be leary of the devices performance; going forward.
When buying hobbyist products you aren't buying fully vetted solutions. Not all possible configurations have been tried or tested. Manufacturing tests are usually limited. These really are science fair projects for sale. This doesn't excuse poor quality, but it does require some leeway on the purchaser's side.
The person you are dealing with is probably just as interested in debugging as you. I emphasis person because we sometimes forget that an "Online Store" may very well be one or two people working out of a garage.
With those in mind, it is certainly not unreasonable to draw a line in your troubleshooting. If you aren't comfortable (or happy) let the Vendor know. IMHO I think you have lived up to your end of the deal doing some limited poking around. However, I'm not the guy who sold something that isn't working so what I think probably doesn't matter.
When buying hobbyist products you aren't buying fully vetted solutions.
In the UK these is a law called the "Sale of goods act" it states that when you buy something it should be "fit for purpose" it dos not differentiate between sellers. A contract is a contract however incompetent the seller may be.
The person you are dealing with is probably just as interested in debugging as you.
He probably is but he should be doing it on his own time and own expense.
That's fine, and I didn't mind measuring some things for them. They were pretty responsive, sent me board overlays, suggested test points, told me expected voltages etc.
I also photographed the board for them, burnt new software into the chip, and spent quite a bit of time on it. After all, we are both interested in getting it fixed.
Their technical response has been good. However the product as it arrived:
Had the LCD plugged in one pin too far to the left, so it didn't work initially.
Showed 510 mA (as per the photo) current when nothing was plugged in
Showed 11330 mV when testing a known 10.000 V source
I acknowledge that it is advertised as a "beta" product, but I assumed that referred to the software being under development. And I assumed that before shipping they would turn it on and check that it actually worked, and when measuring things, it would show a reading within the advertised error percentage.
With most things I try to do some trouble shooting first. In most cases it is a simple missed plug or firmware or driver update. With a product like this I would go a little further, as you have. I would stop and de-soldering any thing more than a 3 or 4 lead component. Send it back and have them send one that is showing within speck. If some thing was plugged in off by a pin or 2 then some thing may be damaged and it needs more attention.
If I was on there side of the coin I would want it back to do my own diagnostics.
