Quantum with occasional continuous tone on power up

[KyleMurdock]

I have assembled a couple of Quarks, but this is my first Quantum. All appears well, most of the time. Occasionally, when I power it up I get a continuous tone, and no wifi. No readout on the serial console either. If I power it off and back on (using a pull-pin switch) then it will usually (but not always) start working.

Sometimes it works fine 10 power ups in a row, then I can get several in a row where it gives continuous tone.

I've checked all the solder joints multiple times, and tried a different switch (in case there's some weird bouncing going on) and lipo battery for good measure. One other thread mentioned that a continuous tone could indicate a short, but I haven't found any and pressing on components while it is in continuous beep doesn't change it. Any other advice on what to check?

 

[rharshberger]

calling @cerving

 

[BEC]

I built an ION that did this. It turns out in my case it WAS a solder joint to the leads that attach the WiFi module — specifically the one on the ground connection. Look for a blob of solder on the lead that touches the board but didn't flow over it. The result is that it has intermittent contact, so it works properly — sometimes.

 

[waltr]

Interesting you just posted this.
Was at MDRA launch yesterday and when I power a Quantum to check ematch before adding BP got this same continuous beep. Temperature was well below freezing <0C. Did a quick battery check, 2S 300ma Turngy, and looked fine at 7.9V (not full but way more than enough). Aborted launching this one since I was not going to troubleshoot at that temperature.

After getting home (3 hour drive) unloaded rocket and had dinner, check this Quantum again, Powered up with the correct beeps plus connected to WiFi. Ok, nothing basically wrong. Put the ebay outside (16°F) for an hour. Power on and continuous beep again. Quickly changed to a warm battery and got proper beeps.

Today is warmer outside as used the Freezer to chill. Again if Quantum and Battery cold continuous beep. But ok with a different battery. Voltage on battery when cold seems ok.
Put the battery on charger to top it off. Back to freezer. Now powers on fine with correct beeps.

I did think it could be solder joints but went through combination before going there.
A good number of other rockets had Quantums and they all worked fine.
Now need to freeze a few other batteries to see how they act when cold.

I do use the ESP WiFi module Cris uses for the Quantum and have learned that they can and do pull bursts of current on start-up and when the WiFi gets enabled. This tends to keep resets in internal processor when the Voltage droops. The Voltage droop is for very short time and a Voltage meter will not see it (they average). An O'scope is needed. Been there troubleshooting code and hardware using the ESP WiFi modules.

You may have a marginal battery or the Voltage is just a bit too low. Try charging to have it topped off.
You did not show the battery in the pics. Which one are you using?
What is the Battery Voltage?

BEC,
Yes, this could still be a solder joint issue on my and the OP's Quantum.

I'm still doing tests.

 

[BEC]

This is what I had on the back side of my ION that did the continuous-tone thing. Reflowing the solder solved the problem.



@waltr And no battery likes to be cold....interesting story about how one worked when chilled and one didn't unless it was fully charged. When LiPoly batteries were new I was flying a small RC electric powered flying wing on frosty mornings and found flight duration reduced by at least 1/3. The model was powered by various 2s LiPolys around 700 mAh.

 

[waltr]

Yes, with the cold the battery was my first suspect. Also fly Quad-copters and do get less flight time on cold days.

Have a poor solder joint on a ground pin would be consistent with the symptoms. The WiFi module requires good ground connections.

Just tested with two other chilled batteries and one did the continuous beep.
Did a look at my solder joints and they seem fine except one or two. Will reflow these with a touch of fresh solder/flux and re-test.

 

[KyleMurdock]

I reflowed a couple of connections on the wifi module that could have been suspect, and (at the risk of jinxing it) it appears to be working now. No continuous beeps after about 30 power cycles. Thanks for the clue and the pointer, Bernard!

I did wonder if this was related to the temp of the wifi module cycling - as it may have been more prone to happen on a cold power up (that is, first power up when the module is cold). It's in a 70° room, so we aren't talking about really cold though.

I am using this Liperior 500mAh 2S battery. Latest voltage shown on the Quantum web page was 8.5v. I have 2 of them, and both appeared to work fine on the Quark (but it doesn't have the wifi module and the associated power-up draw). If the gremlin returns, I will top off the battery and then try again.

 

[KyleMurdock]

Update: Gremlin returned in reduced capacity- occasional continuous tone on power up. HOWEVER, topping off the lipo batteries seems to have banished it (voltage reported on web page 9.5v). After about 50 power cycles, and various drogue/main test cycles with Christmas tree lights, I haven't had a single continuous tone on power up.

So, what I learned today, was that even though a battery appears to be delivering enough voltage, and works fine with other flight computers, it could cause weird things to happen with something that draws a lot of current on power-up, like the Quantum.

 

[cerving]

Lipo batteries don't like cold temperatures, I don't recommend letting them get below freezing. I have done testing in a freezer near 0F, if you keep the battery warm for as long as possible you shouldn't have any problems with the altimeter itself; it's the battery that's the issue. You may want to put your Lipo in some kind of insulation... maybe a piece of foam. Keeping it warm in your vehicle until shortly before launch is prudent.

 

[BDB]

I fly with Quantums slmost exclusively, and I’ve seen some of this behavior too. When I fly on frozen Lake Winnipesaukee in New Hampshire, I zip-tie one of these into my E-bay to try to keep things warm. I do the same to the parachute bundle if I’m flying with a chute release.

 

[waltr]

Latest voltage shown on the Quantum web page was 8.5v.

voltage reported on web page 9.5v

You really need to use a Voltmeter to measure the battery. Then adjust the voltage measurement in the Quantum (details in the instructions).
That 500mA-hr LiPo should be good and at 70°F should not have any problem powering the Quantum...

Cris,
Exactly why I first suspected the battery at the launch Saturday, <0°C.

BDB,
Excellent idea. I did go through four of those hand warmers for my hands Saturday.

 

[cerving]

FYI, I just got a support email from a customer who had three Quantum flights at -5F... using pre-warmed batteries. No issues, consistent with my testing too... the battery craps out way before the altimeter does. Running them in a test freezer at about 0F worked for about an hour, after which time the 800 mAH battery gave up the ghost. Putting a new battery at room temperature in there worked immediately. Keep you battery warm, and fly as soon as you can... sitting on the pad for an hour in sub-freezing cold is not good on the battery.

 

[waltr]

Yep, I did a lot of testing in the freezer on Sunday. Found the same thing, The Quantum works fine at 0°F whereas the battery does not.
At the launch Saturday a number of rockets did fly with Quantums, one rocket had 3 Quantums in it, and they all worked properly. Just don't know what batteries they used or if the had warmers for the batteries.