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Changed transmitter, 15% savings on watt-hours wtf?!?

I had a spectrum transmitter/receiver, changed over last night to a mini-remote.
My commute to work is really consistent. 98 watt hours+/-5.
This morning my commute took 82 watt hours… I can’t think of a good reason why the transmitter change made such a significant economy change.
From what I can see of the transmission in the vesc-tool setup wizard, the broadcast from transmitter is about the same. the only thing I changed in motor controller was to calibrate for this controller, same as I had done for the spectrum.
Theories? and if you have one, suggestions on how to test? thanks!

Reason for changing is a skittish transit cop – the hopped-up mall cop put his hand on his weapon as I was walking past – it was obvious from what he was looking at, that he thought my remote might be a gun. Personally, i think someone needs to take some Xanax or indulge in some of the relaxing things that Denver has to offer, rather than being that much on edge that a fat middle-aged dude with a skate board almost has you drawing.
I prefer the spectrum remote, but I’d rather change than die fulfilling some meat-head’s hero fantasy

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cool remote OP. are all the other buttons programmable?

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I like the theory, if so, I’ll see a return to normal over the next couple of days. I’ll keep watching

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nice, apparently the transmitter i used to use should be spelled ‘Spektrum’

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Spektrum was the first one to come out w a remote that doesn’t use “crystals” back in the day for RC racing. It was a game changer w connection reliability. We didn’t have to tell, “who’s on green or who’s on 15” anymore. It’s a little overkill for ek8.

I thought of using my sanwa mt44 for esk8 but it was too big

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After a full week of commuting, and a weekend of screwing around – I can say that the mini-remote is consistently better for my battery – 13-5% better.
My current theory is the specktrum transmitter is ‘noisier’, which I guess means the Vescs and motors are spinning up and down more – not so I’d perceptually notice, but enough to waste power. Now I have to figure out how to test.

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This is my favorite remote, and I am very happy to hear this, but I absolutely am confused what science could cause this.

We really need to get to the bottom of this.

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I considered that the receiver draw could be the cause, but testing that hypothesis showed it to be likely false.
I manually charged via a balance charger that displays watt-hours charged. then left it turned on for 7 hours(over night 0000-0700). Charged again and did the same with the mini-remote receiver. 12 watt hours for the specktrum, 13 for the mini. the amount difference could easily be measurement error, but close enough to be discarded as the main cause for the ‘mileage’ difference.

Observationally , with the spektrum remote, I just slowly pull the trigger until I hit my desired speed, whereas with the mini, I have to back-off the trigger once I hit desired speed. I’m wondering if my settings on the specktrum means that the PWM signal it puts out deliberately overshoots, then backs off.

Since I don’t have a SDR tool to directly measure this, I think I’ll use the vesc tool to display the PWM. I’ll use a piece of plastic to block the trigger from going all the way (I’ll target about 50%) for each remote, map the range and hopefully catch what’s going on.

Alternatively, anyone know where I can get a good SDR USB dongle for about $20 that can hear and distinguish r/c signals?

I think I have the answer:
.
hooked up vest-tool, used input wizard to see what signal each remote was sending.

mini-remote at about 50% throttle OR 50% brake had much less jitters in signal than the specktrum. The mini had a jitter of ±50ms, the specktrum -+100ms. At neutral and full throw, they are about the same. I imagine that the constant speed up/slow down that the Vescs were seeing would adequately explain the efficiency loss.

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Can’t wait to check my osrr/vx1 and compare it to your findings! Seems very cool

If you streetface with your new remote you’ll know why, the Spektrum has more robust “noisier” frequency hopping tech, which may account for the higher power drain.

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that is my fear, and why I used the spektrum in the first place…
but I’d rather eat asphalt than have some roided-out LEO draw down because he can’t distinguish between a remote and a gun in broad daylight; which almost happened once. I’m not risking that a second time without a better reason.

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