Adding control of variable

I've found this code that produces the effect I'm going for and want to add an input to control a variable (brightness) with a pot on a tx/rx. I'm testing with a wired pot before setting up the rx. Don't think that should matter. I added a few lines that I thought would work, but no dice. I put the notation "added for remote control" on the lines I added. Any help would be appreciated.

#include <Adafruit_NeoPixel.h>
#ifdef __AVR__
  #include <avr/power.h>
#endif

#define PIN 11

//  The overall fire brightness
//  (this can affect both color levels and power consumption)
int brightness = 0; //added for remote control
int rxPin = 9;      //added for remote control

// Parameter 1 = number of pixels in strip
// Parameter 2 = Arduino pin number (most are valid)
// Parameter 3 = pixel type flags, add together as needed:
//   NEO_KHZ800  800 KHz bitstream (most NeoPixel products w/WS2812 LEDs)
//   NEO_KHZ400  400 KHz (classic 'v1' (not v2) FLORA pixels, WS2811 drivers)
//   NEO_GRB     Pixels are wired for GRB bitstream (most NeoPixel products)
//   NEO_RGB     Pixels are wired for RGB bitstream (v1 FLORA pixels, not v2)
Adafruit_NeoPixel strip = Adafruit_NeoPixel(13, PIN, NEO_GRB + NEO_KHZ800);

// IMPORTANT: To reduce NeoPixel burnout risk, add 1000 uF capacitor across
// pixel power leads, add 300 - 500 Ohm resistor on first pixel's data input
// and minimize distance between Arduino and first pixel.  Avoid connecting
// on a live circuit...if you must, connect GND first.
// For the ultimate NeoPixel guide, check out:
// https://learn.adafruit.com/adafruit-neopixel-uberguide/overview

void setup() {
  strip.begin();
  strip.setBrightness(brightness);
  strip.show(); // Initialize all pixels to 'off'
  pinMode(rxPin, INPUT);    //added for remote control
}

void loop() {
  analogRead(rxPin);              //added for remote control
  map(rxPin, 0, 1024, 40, 100);   //added for remote control
  brightness = rxPin;              //added for remote control

  //  Uncomment one of these RGB (Red, Green, Blue) values to
  //  set the base color of the flame.  The color will flickr
  //  based on the initial base color
  
  //  Regular (orange) flame:
    int r = 225, g = 50, b = 0;

  //  Purple flame:
  //  int r = 158, g = 8, b = 148;

  //  Green flame:
  //int r = 74, g = 150, b = 12;

  //  Flicker, based on our initial RGB values
  for(int i=0; i<strip.numPixels(); i++) {
    int flicker = random(0,55);
    int r1 = r-flicker;
    int g1 = g-flicker;
    int b1 = b-flicker;
    if(g1<0) g1=0;
    if(r1<0) r1=0;
    if(b1<0) b1=0;
    strip.setPixelColor(i,r1,g1, b1);
  }
  strip.show();

  //  Adjust the delay here, if you'd like.  Right now, it randomizes the 
  //  color switch delay to give a sense of realism
  delay(random(15,113));
}

What do you mean "pot on a tx/rx"?

Instead of:

  analogRead(rxPin);              //added for remote control
  map(rxPin, 0, 1024, 40, 100);   //added for remote control
  brightness = rxPin;              //added for remote control

Try this:

  int temp = analogRead(rxPin);              //added for remote control
  brightness = map(temp, 0, 1024, 40, 100);   //added for remote control

that's a potentiometer on a radio transmitter. rx is the receiver. Thanks, I'll try this.

Billyprps:
that's a potentiometer on a radio transmitter. rx is the receiver. Thanks, I'll try this.

Gotcha. I know what rx and tx are I just didn't know what type of comm you were speaking of.

Links to datasheets/product-pages for all the hardware?
Circuit diagram for how its connected?

We need the details to figure anything out...

Explain both what you expect to happen and what is actually happening - that way
we have a chance of understanding what you want...

int rxPin = 9;      //added for remote control
  analogRead(rxPin);              //added for remote control

That's not going to work on an UNO which has only 6 analog input pins.