RCU Forums - View Single Post - Intro to the Open Panzer Project - and a new Tank Control Board
Old 07-17-2017, 08:54 AM
  #182  
LukeZ
 
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What we know so far:
  1. At least some but perhaps all boards manufactured by Hobby King were built with an incorrect component. Specifically MOSFETs Q1 - Q8 were replaced with non-functional versions. These control all the light outputs as well as the airsoft motor.
  2. User jhamm has confirmed that when these components are replaced with the correct MOSFETs, the board works as expected. Thank you jhamm for your help!
  3. Hobby King made several prototypes before production, two of which I tested personally: one in October 2016 and the second in January 2017. Both worked flawlessly. That is not to count the many boards I built myself, several of which have been sent to other users including Erik at Taigen, none of which have shown any hardware issues to date.
  4. In short, there is nothing wrong with the Open Panzer TCB design.
  5. I provided Hobby King a bill of materials identical to the one posted publicly on the Open Panzer website. The version I gave them also had an extra bit of information - which components they were free to substitute with equivalent parts in order to save money, and which component must not be substituted. MOSFETs Q1 - Q8 were on the do not substitute list.
  6. Nevertheless, for reasons unknown, Hobby King did substitute those parts, and the board is therefore lacking several functions.
  7. I specifically requested a board from the production line before they went on sale and was told repeatedly it was being sent, but to this day I have never received it and as of yesterday they admitted it still hadn't even been shipped.
  8. HobbyKing was notified of this issue last Saturday when jhamm notified me. Monday in HK has now come and gone and all they've managed to accomplish is pull the product listing and tell me they are looking into it and will let me know the results when they have completed their tests. I told them we already know the results, and what we need is a statement from HobbyKing indicating what they plan to do about it.
So that's where we're at. We know what happened, but not how or why. Maybe it was a cost-saving measure, although these MOSFETs cost roughly 10 cents a piece in the quantities they would have needed. No doubt there are substitutes that would have worked equally as well, so if they were going to deviate from the specification at least you'd think they'd choose a functional replacement. For that reason I wonder if maybe it was a simple mistake, maybe a tech loaded the wrong thing into the pick-and-place machine. Hopefully they will let us know. If they deliberately used a non-functional part then we can assume 100% of the boards are defective. If they just made an accident at one point in the production run, potentially some boards may have turned out ok. Without a clear answer from them I can only speculate at this point.

Obviously this is incredibly frustrating to those who ordered boards as well as everyone who has waited so long to see this project gain some legs. It is definitely a disappointment and a setback.

I will keep you updated as I get more information from Hobby King.


Luke

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Last edited by LukeZ; 07-17-2017 at 09:04 AM.