nRF24L01 Module will only work when connected to computer via USB

I am using a 9V battery connected to Vin and ground on both the transmitter and receiver. One each. I apologize for the confusion, the two boxes on the bottom left are my joysticks. They should both be connected to Vy I apologize for the mistake. But the joysticks only require a 5V, GND, and analog pin connection. In the diagram I have them connected to 5V and GND Aswell as A0 and A1. 

I don't believe my joysticks or my nRf24L01 chip needs an isolation capacitor because in the host's article, he says that by using one of these adapters, it takes away the need to put an additional capacitor on because the board comes with it's own. 

@jettedlikeshek 

OK, I agree with @zander and @davee that your problem is the battery. It can only supply about 500mA for an hour or so IIRC.

So, if you had it plugged in and playing with the car for any length of time you will have run down the battery somewhat. When you add in the fact that you're losing more power by running the battery's 9V through a converter down to 5V and then into the NRF board which can consume 300mA peak, you can see that it won't take too long to run down the battery.

Running from the USB allows access to a nominal USB port limit of 500mA which does NOT suffer from diminishing voltage nor does it have a built-in chemical time limit. So it seems that it will always be capable of powering the device as long as needed.

You may need to upgrade your power source to a better class of 9V battery, use fresh 9 batteries for each demo or use a bank of AA, C, D or even 18650 cells to make up the (<12V) to power the circuit.

I'm very surprised that you're not having similar problems with the receiver, so I'd advise you to examine the transmitter very carefully, specifically to look for shorts or bad solder joints.

PS you should click on the Reply button when you respond. That sends an email to the member so that they know you answered. If you don't click it, they won't see your answer until they're on next time and happen to look at the thread.

@will Okay sweet, I am going to look for a replacement to the 9V. Do you happen to know a better class of 9V? I am using alkaline right now would lithium work or should I jump straight to a pack of AA?

Thank you for the advice this is my first ever post.

@jettedlikeshek 

Check the wiring and all your solder joints first; that's free and doesn't require any time waiting for the goods to arrive.

I can't advise you about batteries because I rarely use anything but 18650s any more.

@jettedlikeshek Really?

better class of 9V?

I think what you mean is 'more powerful', and since we are talking only about a voltage of 9V, what that translates into is something called capacity. Capacity is measured in Amp Hours or for smaller batteries mAH.

A simple search for 9V and some higher capacity better than the 550mAh you now have will get you what you want, BUT, why 9V, isn't the highest voltage used in your circuit 3.3V or 5V, if so, then look for that.

However, does it need to be battery operated, or can it be plugged in. If it can be plugged in, then any wall wart with a 5V output will suffice.

REMEMBER, keep the 5V away from the nRF24L01 VCC pin.

Hi @jettedlikeshek,

 I am sorry, but I am not clear what power source you are using for the NRF24L01 module/adapter ... the diagram just says VCC.

If VCC is some other 'supply', then the grounding  of that supply needs to be joined to the other grounds.

If you mean the 5V pin on the Arduino, then this could be your problem. When the Arduino is powered via the (cylindrical) power plug, the incoming voltage of (say) 9V is reduced to 5V by a small regulator, that is the supply for the Arduino processor, and anything you connect to the 5V pin. This pin should be fine for your joystick potentiometers. but not the nRF24L01 ... which Bill, myself, and others have pointed out.

When powered by USB, this regulator is not in the current path, so its limited current ability is not limiting the power available for the nRF24L01.

Best wishes, Dave

@zander Yes, I'm thinking I need something with more current in order to power everything. Based on the Arduino nano datasheet, it says the input voltage should be 7-12V. I believe that voltage is regulated down to a steady 5V and that is used to power everything from the nano. Having a power supply of equal or less than 5V would mean it would probably be underpowered. 

Yes, I am building an RC car so I need it to be wireless. 

@davee Right now, I am using the 5V pin from the Arduino to power the VCC on the nRF24L01 Adapter Module. Which is correct because in the host's article he connects it to the 5V pin (I placed an image of the article in a previous post).

I am confused as to why this wouldn't be sufficient for the nRf24L01 adapter module. If the LDO regulator takes the 9V down to 5V and provides a steady 5V continuously, why wouldn't it provide a constant 5V to the adapter module as well?

@jettedlikeshek You need to learn how to read specs including datasheets. Start at arduino.cc click hardware, click NANO family, click NANO. You will see the following

The NANO has 3 (THREE) power inputs, USB (5.1VDC), regulated 5VDC on pin 27 labelled +5V and unregulated 6VDC to 20VDC on pin 30 (last pin) labelled VIN. The NANO will choose the highest voltage pin.

Since you are building a car, your best bet is a 9V battery JUST FOR THE NANO. That goes to pin 30 and NO other power on the other power pin 27 and USB.

Now you need a 18650 power pack for the motors, I leave it to you to figure that out. Be careful, the 18650 is the most counterfeited device on the internet. From that big power bank, take a Buck converter (probably an LM2596) to reduce the motor power to the 5V needed for the nRF adapter you already have that will convert the 5VDC to a regulated 3.3VDC for the radios.

18650 pack of ? Each cell is 3.7VDC so if motors are 12V then 4 cells in series is 14.8. I don;t remember if you need to step that down to exactly 12V for a motor, or can the motor work with more. Many motors are spec'd at 6VDC to 24VDC so 14.8VDC is great. If you need longer run time on the motors, just parallel 2 more cells into a 2S2P, even more, 2S3P etc. If motors will take more Volts, then add additional in series to get to just under the max voltage but I suspect a 2S2P is all you need.

SUMMARY:

Motors powered by a 2S2P 18650 battery pack (will need a charger, this is adequate but does not do storage or capacity. I have one that does everything but costs $200 https://amzn.to/3xOhwB5 )

NANO 9V battery

nRF24L01 radios, motor power to BUCK converter (5VDC) to nRF24L01 adapter (3.3VDC) to radios.

Posted by: @jettedlikeshek

↑

@davee Right now, I am using the 5V pin from the Arduino to power the VCC on the nRF24L01 Adapter Module. Which is correct because in the host's article he connects it to the 5V pin (I placed an image of the article in a previous post).

I am confused as to why this wouldn't be sufficient for the nRf24L01 adapter module. If the LDO regulator takes the 9V down to 5V and provides a steady 5V continuously, why wouldn't it provide a constant 5V to the adapter module as well?

It may be possible to power 1 joystick from the NANO +5VDC, but two is likely a problem. Just use an LM2596 fed from the motor battery to give you plenty of 5VDC power for the radio adapters.

@zander Pin 30(Vin) is connected to a regulator which takes it down to 5V. I assume you know that anything above 5V will be lost to heat because of the LDO regulator. I have been using a 9V because it provides more than enough voltage without losing too much to heat but that has stopped working. I have no other pin connected to power.

This is for the transmitter; I do not have the battery for the motors on my controller. That would be on the car. 

On the transmitter side, it is wired in the diagram I posted most recently in a previous post. 

For the receiver I am using a 11.1 V 5000 mAH Traxxas RC car battery connected to a DC5-12V motor controller. The motor controller takes a max of 14.5V and is capable of outputting I believe a continuous 20A of current which is far above my needs. I just need it to drive two 775 motors which take about 4-10 A of current. For the Arduino I have a 9V battery powering that. The car drives and works pretty well when everything is connected so I am not too worried about power going to the motors. It's just the reliability of the nRf24L01 chips and getting them to work again is what I'm struggling with. I'm thinking of trying lithium 9V batteries and then if that doesn't work a pack of AA batteries and hopefully either of those solve my issue. I agree it is definitely a power issue as my computer can make it work but a single battery can't.

@zander If I were to purchase and use two 18650 batteries of a total voltage of 7.4 with 5000maH of current would that be too much? I am talking about for the transmitter.  5000 maH of current going into Vin scares me.

@jettedlikeshek Ok, I was a bit confused. So the car and receiver are ok, right?

It's just the transmitter that is a problem, right?

Assuming that's right, I would get a power bank for the transmitter. Plug the NANO into the power bank using a standard or power only USB cable, then modify an old USB cable (ideally a power only) to power the nRF adapter (that means cut end off and strip power leads after identifying (2 outermost, ground goes to shield))

Alternatively a bunch (6) of AA or a couple of 9V will also work but probably bigger and more tedious to recharge unless disposable. 4 AA is not enough power especially the rechargeable kinds.

The 2 9V in parallel will be unbalance so will cross charge, be aware or use some diodes, ideally schottky I think.

@jettedlikeshek First of all there is no such thing as a 5000mAh 18650. Capacity is a function of weight (actually volume but easier to weigh) Depending on the battery it will be from 1200 to maybe 3600) As I said the most faked item. They will also require a charger costing at least $30 for one that will eventually destroy your batteries, to $200 for a professional unit. I might still have the first $40 unit I bought before I got the correct charger. I would ship it to you buy the cost would be about the same.

In any case, yes 2 18650's will do it but that introduces a few problems. As I said in another post just posted, a powerbank is a fool proof way to go.

VERY important, current is DRAWN, not pushed. Use the garden hose analogy, voltage is pressure and current is volume.

@jettedlikeshek I looked up what the weight is of a legal 18650, and it's at least 42gm, and can get up to 45gm. Here are a few of mine that I have tested with a professional capacity tester. The last I don't know the rating of but based on cryptic markings I am guessing 2210 but probably higher.

1. Marked as 2200 tested at 1818 42.8gm with embedded protection chip.
2. Marked as 2000 tested at 2000 43.8gm with embedded protection chip.
3. Guessed as 2210 tested at 2452 43.2gm with embedded protection chip.

These are all LiIon batteries. There are 5 chemistries but are collectively known as LiI or LiIon. The safest chemistry is LiFePO4 and it is 3.2V. I have 6 100AH 12VDC batteries under my bed in my RV, they are safe. Also available in 18650 size.

There is another group of unsafe Lithium called LiPo or battery in a bag. They require a different charger which I also have plus of course the big RC battery charger you must have for your car motor drive batteries. These are the infamous batteries that burn like hell especially if not charged with a balance charger.

I found this description which agrees with what I know other than voltage, I call them 3.7V, not 3.6V.

An 18650 battery is a lithium-ion battery. The name derives from the battery's specific measurements: 18mm x 65mm. For scale, that's larger than an AA battery. The 18650 battery has a voltage of 3.6v and has between 2600mAh and 3500mAh (mili-amp-hours).

NOTE, no 5000mAh possible.