eggtimer quantum powers up with solid beeeeeeep- any ideas

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
the quantum worked perfectly this morning, ran through ground tests- perfect. It's on a board, and when I powered it up this afternoon, it is just sitting there beeeeeeping. no light diode.
 
Do you have standoffs on the board? If you don't, those components on the bottom can be damaged by pushing down against the board... and it's tough to troubleshoot.
 
I sometimes used nylon standoffs with metal screws along with locknuts below the plywood mounting board. I then would apply plywood thrust blocks to secure the deployment altimeters both fore and aft with the best epoxy I could find. I used some Aerospace grade stuff one time (2545B) but I think J&B Weld would work good enough for thrust blocks. Just made sure the thrust blocks were just the right distance so I got to get the planned altimeter in and out but still had contact with the reinforced thrust blocks. Never had a problem with that setup. Kurt
 
I have built 7 of the Quantum altimeters. One of the latest boards had that same issue. I had performed a power up test and it came up normally. I then realized I hadn't put the FET and the terminal block in. After soldering those, the board would only beep. In testing the drogue output measured 8.1 volts open and the main measured 4.1 volts. Compared it to a known good altimeter which measured 4.1 volts for both. Re-soldered the driver for that channel and all is well. Check your open circuit voltage on the terminal block. Might have a cold solder joint that had good contact until it got jostled just right.
 
Do you have standoffs on the board? If you don't, those components on the bottom can be damaged by pushing down against the board... and it's tough to troubleshoot.
the 3.3 v voltage regulator is too hot to touch. would this part failure cause the never ending beeeeeep at startup ( it never starts up) symptom I am describing?
 
the 3.3 volt voltage regulator is extremely hot. too hot to touch.

would a fried voltage regulator cause a solid beeeep at powerup?
ah ok you should have mentioned that at the start, any electronic component that is too hot to touch is a massive red flag. It means you either have a bad regulator or somewhere on the board is drawing a massive amount of power (like a short) it’s usually the second one. You really should find the cause before you can turn it back on or else you risk damaging the 3.3v regulator or something else.

edit: it could be the cause of the beep or it’s just another clue, but I would take a very close look around the buzzer and 3.3v regulator to see if there is any shorts or damage. If you dont see any start looking outwards from the 3.3v regulator or buzzer.
 
I have one that is doing nearly the same thing. 3.3v regulator heats up and then it starts a solid tone. I've flown mine twice in the past without issue and then this started 1 month ago. Board rev A18. I was going to swap the regulator and start searching for shorts but they're so cheap, I'm going to swap one from my stock and retire the failed one.
 
Note that the regulator (it seems to me) generally runs warm, bordering on hot, on all the Quantums I've made. Originally I was worried about it and measured the current draw, but didn't find anything excessive and just figured it's the way this design runs.

My point being that I don't know if the warm/hot regulator is necessarily a symptom of a problem.
 
Back
Top