Dynon's 2nd Reply

And more of the same. Here's the next level of the exchange - probably the last.

Robert,

I'm not sure if I want to go through the ADAHRS swap again. It's a pain to work in the tailcone at a 100+ degF with my head below my feet to swap a unit that's working at this time. The offer is not that tempting considering the effort I would have to put in on my side, to just get what I should have had 2 swaps ago if the new unit would have been working. And you'd probably expect me to pay for the shipping again, too.. Sounds more like a continuation of what I have criticized before.

The OAT in my previous ADAHRS was consistently not working as documented in my building blog. I tried everything to not having to take it out and I was very thorough when debugging it, so I wouldn't remove something that's in working order.
I just hope you don't send this ADAHRS unit to someone else as perfectly working and tested.

Anyway, this discussion doesn't seem to go anywhere and you're not really offering me anything to make up for the issues that I have addressed in my previous email. Obviously, you feel that your policies are working out for you and I don't. I suppose you'll move on continuing what you're doing and so will I and my decision to choose a different avionics manufacturer with my next project still stands.

Torsten.

On 07/03/2012 04:49 PM, Robert Hamilton wrote:
> Torsten,
>
> Thank you for the detailed reply. I know you feel strongly about this, and I truly am sorry that you had any problem with Dynon equipment. And as a consumer myself, I know I have high expectations of companies I purchase from.
>
> The disturbing thing you told me was that the ADAHRS brass pneumatic connections were corroded. They are supposed to be in new condition before being put in the re-manufactured inventory. If you want me to swap you a new ADAHRS for that reason I will.
>
> So now I have two choices here. I can leave it at an apology and the offer above. Or I can tell you the facts at my disposal, at the risk of making you even less satisfied with us. My choice is the latter, because you paid a lot of money, are interested, and deserve all the facts. Which are:
>
> * We do a complete burn-in on all of our electronics. On the ADAHRS it receives a 24 hour burn-in plus a 48 calibration cycle including temperature extremes. On selected equipment we also perform a 45 hour HASS type test. The owner of our company made his fortune at semiconductor manufacturing, and we know electronics very well.
>
> * On the servo we got back, the problem was that the 485 data communication chip was burned out. The most likely cause for that result is that a voltage was applied to the data lines. I am at a loss to explain why that chip would go bad for any other reason. It did not have the appearance of a random chip failure, which in any case are extremely rare after burn-in.
>
> * On the SV-ADAHRS-200 we received back, the OAT port and circuitry is in perfect order. It worked immediately upon an OAT being plugged in. We then subjected it to -50 deg C and +150 deg C, and it worked perfectly. We then subjected it to vibration and manual poking and prodding and there were no problems. We visually inspected the circuitry and there are no breaks or cracks.
>
> Because I was interested in this, I was physically there while these tests were performed, and so can verify the results first hand. There was absolutely no interruption in the OAT data, no matter what we did to the connection.
>
> So that is the information I have, and what I face on a daily basis. Often we can point to a product defect. Often we can't.
>
> -Robert