Radio Frequency power detector "sniffer"

1/*
2 * ard-rf-sniffer (instrument monitor or threshold alarm)
3 *  by Marco Zonca 05/2022
4 * 
5 * LT5534 50-3000Mhz rf detector IC, ATTiny1614  3.3V MCU, LIR2450 rechargeable battery, MCP73831 4.2V charger IC, active buzzer,  
6 * 2x 2 pos. dipswitch, trimmer, RGB led, red led, SMA-F antenna, SMA-M panel  connector, on/off switch, some SMD resistors and capacitors
7 * 
8 * Remember  to connect a specific antenna for every rf frequency range you want to detect;
9  * in some cases a simple ring wire of any lenght can be enough as "antenna", expecially  when the rf signal is strong
10 * 
11 * LT5534 datasheet says to not overcharge  the rf input pin with signals > 10dbm (i.e. handheld 5W radio tx near the IC);
12  * if it is the case, I suggest to put an attenuator between the antenna and the  circuit (i.e. 20dbm SMA-MF serial attenuator).
13 * Additionally use full metal  box or, as I did, cover the interiors of the plastic box with copper foil to avoid  signals passing trought,
14 * or paint/spray with conductive material the interiors  of the box (i.e. graphite).
15 * 
16 */
17
18byte pin_ledred = 0;
19byte pin_ledgreen  = 6;
20byte pin_ledblue = 7;
21byte pin_DS1_instrcomparat = 1;
22byte pin_DS1_buzz  = 2;
23byte pin_DS2_bit1color = 3;
24byte pin_DS2_bit0color = 4;
25byte pin_threshold  = 8;
26byte pin_vrf = 9;
27byte pin_buzzer = 10;
28
29byte a=0;
30byte b=0;
31
32bool  isBuzzer=false;
33bool isInstrument=false;
34byte ledColor=0;
35byte pin_LED=0;
36byte  buzlevel=250;  // buzzer loudness: 125/255 (125=50%, max 255=100%)
37byte Off=0;
38byte  On=75;  // led brightness: 75/255 (75=30%, max 125=50%)
39
40int rfSignal=0;
41int  rfThreshold=0;
42int setBUZ=0;
43int setLED=0;
44
45long LedblinkMillis=10000;
46unsigned  long prevLedblinkMillis=0;
47long ReadSetupMillis=2000;
48unsigned long prevReadSetupMillis=0;
49
50void  setup() {
51  pinMode(pin_ledred, OUTPUT);
52  pinMode(pin_ledgreen, OUTPUT);
53  pinMode(pin_ledblue, OUTPUT);
54  pinMode(pin_buzzer, OUTPUT);
55  pinMode(pin_DS1_instrcomparat,  INPUT_PULLUP);
56  pinMode(pin_DS1_buzz, INPUT_PULLUP);
57  pinMode(pin_DS2_bit1color,  INPUT_PULLUP);
58  pinMode(pin_DS2_bit0color, INPUT_PULLUP);
59  pinMode(pin_threshold,  INPUT);
60  pinMode(pin_vrf, INPUT);
61  readSetup();
62  initialShow();
63  prevLedblinkMillis=millis();
64}//setup()
65
66void loop() {  // ------------------------------------------------------------>
67  rfSignal=analogRead(pin_vrf);
68  rfThreshold=analogRead(pin_threshold);
69  if (isInstrument) {  // -------- instrument monitor
70      setBUZ=map(rfSignal,rfThreshold,1023,0,buzlevel);
71      if (isBuzzer) analogWrite(pin_buzzer,setBUZ);
72      setLED=map(rfSignal,rfThreshold,1023,0,On);
73      if (pin_LED != -1) analogWrite(pin_LED,setLED);
74      delay(100);
75      if  (isBuzzer) analogWrite(pin_buzzer, Off);
76      if (pin_LED != -1) analogWrite(pin_LED,Off);
77    } else {  // ----------------- threshold alarm
78      if (rfSignal > rfThreshold)  tAlarm();
79  }
80  if ((isInstrument==false) && (prevLedblinkMillis + LedblinkMillis)  < millis()) blinkLed();
81  if ((prevReadSetupMillis + ReadSetupMillis) < millis())  readSetup();
82}//loop() --------------------------------------------------------------------<
83
84void  tAlarm() {
85    for (a=1;a<=3;a++) {
86      if (pin_LED != -1) analogWrite(pin_LED,On);
87      if (isBuzzer) analogWrite(pin_buzzer, buzlevel);
88      delay(200);
89      if (pin_LED != -1) analogWrite(pin_LED,Off);
90      if (isBuzzer) analogWrite(pin_buzzer,  Off);
91      delay(200);
92    }
93}//tAlarm()
94
95void blinkLed() {
96  if (pin_LED != -1) {
97    analogWrite(pin_ledgreen,On);
98    delay(200);
99    analogWrite(pin_ledgreen,Off);
100    delay(200);
101  }
102  prevLedblinkMillis=millis();
103}//blinkLed()
104
105void  initialShow() {
106  if (isBuzzer) analogWrite(pin_buzzer, buzlevel);
107  analogWrite(pin_ledred,On);
108  delay(200);
109  if (isBuzzer) analogWrite(pin_buzzer, Off);
110  analogWrite(pin_ledred,Off);
111  analogWrite(pin_ledgreen,On);
112  delay(200);
113  analogWrite(pin_ledgreen,Off);
114  analogWrite(pin_ledblue,On);
115  delay(200);
116  analogWrite(pin_ledblue,Off);
117  delay(200);
118}//initialShow()
119
120void readSetup() {
121  isBuzzer=!digitalRead(pin_DS1_buzz);
122  isInstrument=!digitalRead(pin_DS1_instrcomparat);
123  a=!digitalRead(pin_DS2_bit0color);
124  b=!digitalRead(pin_DS2_bit1color) * 10;
125  ledColor=a+b;
126  switch (ledColor)  {
127    case 0:
128      pin_LED=-1;  // no led
129    break;
130    case 1:
131      pin_LED=pin_ledred;
132    break;
133    case 10:
134      pin_LED=pin_ledgreen;
135    break;
136    case 11:
137      pin_LED=pin_ledblue;
138    break;
139  }
140  prevReadSetupMillis=millis();
141}//readSetup()
142