user49877: I have a Futaba S148 servo (https://servodatabase.com/servo/futaba/s148)
connected to an Arduino Uno.
As soon as the script attaches the servo, it rotates to its limit and gets stuck.
I've tried several scripts, and narrowed to the simplest: 
#include <Servo.h>  // servo library
Servo servo1;  // servo control object
void setup()
{
  //  Attach the servo1 object to digital pin 4.
  servo1.attach(10);
}
void loop()
{
}

Also connected the servo to the board with this: 
#include <Servo.h>  // servo library
Servo servo1;  // servo control object
void setup()
{
  //  Attach the servo1 object to digital pin 4.
  //servo1.attach(10); <--- notice this commented out
}
void loop()
{
}

and then the servo remains still. 
I'm using a battery pack of 4.8 V which works fine with the servo and the RC radio, so the battery and the servo, works fine together with remote control.
I have another different SG90 servo running with its own power source and connected to the pin 9, and with a different sketch, it works perfectly.

user-1: https://www.arduino.cc/en/Reference/ServoAttach - This should answer it. The library you are using supports only 2 specific pins

49877: <p>I have a Futaba S148 servo (<a href="https://servodatabase.com/servo/futaba/s148" rel="nofollow noreferrer">https://servodatabase.com/servo/futaba/s148</a>)
connected to an Arduino Uno.</p>

<p>As soon as the script attaches the servo, it rotates to its limit and gets stuck.</p>

<p>I've tried several scripts, and narrowed to the simplest: </p>

<pre><code>#include &lt;Servo.h&gt;  // servo library
Servo servo1;  // servo control object
void setup()
{
  //  Attach the servo1 object to digital pin 4.
  servo1.attach(10);
}
void loop()
{
}
</code></pre>

<p>Also connected the servo to the board with this: </p>

<pre><code>#include &lt;Servo.h&gt;  // servo library
Servo servo1;  // servo control object
void setup()
{
  //  Attach the servo1 object to digital pin 4.
  //servo1.attach(10); &lt;--- notice this commented out
}
void loop()
{
}
</code></pre>

<p>and then the servo remains still. </p>

<p>I'm using a battery pack of 4.8&nbsp;V which works fine with the servo and the RC radio, so the battery and the servo, works fine together with remote control.</p>

<p>I have another different <a href="https://servodatabase.com/servo/towerpro/sg90" rel="nofollow noreferrer">SG90 servo</a> running with its own power source and connected to the pin 9, and with a different sketch, it works perfectly.</p>
 -1: <p><a href="https://www.arduino.cc/en/Reference/ServoAttach" rel="nofollow noreferrer">https://www.arduino.cc/en/Reference/ServoAttach</a> - This should answer it. The library you are using supports only 2 specific pins</p>
