diff --git a/HamShield.cpp b/HamShield.cpp
index 7fe816a..eae5b2f 100644
--- a/HamShield.cpp
+++ b/HamShield.cpp
@@ -384,7 +384,7 @@ void HamShield::setTX(bool on_noff){
       setGpioLow(5); // remember that RX and TX are active low
       // then turn on VREG (PWM output)
       // then apply RF signal
-      setRfPower(100); // figure out a good default number (or don't set a default)
+      setRfPower(9); // figure out a good default number (or don't set a default)
     }
 
     // todo: make sure gpio are set correctly after this
@@ -943,19 +943,12 @@ void HamShield::setRfPower(uint8_t pwr) {
    // (see RF6886 datasheet)
    // 30 is 0.5V, which is ~min loop reference voltage
    // 127 is 2.5V, which is ~max loop ref voltage
-   int max_pwr = 255; //167; // 167 is 3.3*255/5 - 1;
+   int max_pwr = 15; //167; // 167 is 3.3*255/5 - 1;
    if (pwr > max_pwr) {
      pwr = max_pwr; 
    }
   
-  
-   // using open loop reference voltage into Vreg1/2
-   /*int max_pwr = 78; // 78 = 1.58*255/5 - 1
-   if (pwr > max_pwr) {
-     pwr = max_pwr; 
-   }*/
-   // using loop ref voltage as specified in RF6886 datasheet
-   // analogWrite(pwr_control_pin, pwr);
+   I2Cdev::writeBitsW(devAddr, A1846S_PABIAS_REG, A1846S_PADRV_BIT, A1846S_PADRV_LENGTH, pwr);
 }
 
 
diff --git a/HamShield.h b/HamShield.h
index 45949a1..5006af3 100644
--- a/HamShield.h
+++ b/HamShield.h
@@ -89,6 +89,9 @@
 #define A1846S_PABIAS_BIT          5  // pabias_voltage<5:0>
 #define A1846S_PABIAS_LENGTH       6
 
+#define A1846S_PADRV_BIT          14  // pabias_voltage<14:11>
+#define A1846S_PADRV_LENGTH       4
+
 // Bitfields for A1846S_BAND_SEL_REG
 #define A1846S_BAND_SEL_BIT        7  // band_sel<1:0>
 #define A1846S_BAND_SEL_LENGTH     2
diff --git a/examples/SerialTransceiver/SerialTransceiver.ino b/examples/SerialTransceiver/SerialTransceiver.ino
index 3733302..ff033a0 100755
--- a/examples/SerialTransceiver/SerialTransceiver.ino
+++ b/examples/SerialTransceiver/SerialTransceiver.ino
@@ -17,7 +17,7 @@ Frequency      F<freq>;    Set the receive frequency in KHz, if offset is disabl
 CDCSS In       G<code>;    <code> must be a valid CDCSS code                                                                                                            No
 CDCSS Out      H<code>;    <code> must be a valid CDCSS code                                                                                                            No
 Print tones    I           Prints out all configured tones and codes, coma delimited in format: CTCSS In, CTCSS Out, CDCSS In, CDCSS Out                                No
-Power level    P<level>;   Set the power amp level, 0 = lowest, 255 = highest                                                                                           No
+Power level    P<level>;   Set the power amp level, 0 = lowest, 15 = highest                                                                                           No
 Enable Offset  R<state>;   1 turns on repeater offset mode, 0 turns off repeater offset mode                                                                            No
 Squelch        S<level>;   Set the squelch level                                                                                                                        No
 TX Offset      T<freq>;    The absolute frequency of the repeater offset to transmit on in KHz                                                                          No
@@ -81,7 +81,7 @@ void setup() {
   radio.setVolume2(0xF);
   radio.setModeReceive();
   radio.setTxSourceMic();
-  radio.setRfPower(255); // 30 is 0.5V, which corresponds to 29 dBm out (see RF6886 datasheet)
+  radio.setRfPower(9);
   radio.setSQLoThresh(80);
   radio.setSQOn();
 }