faq.html

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layout: default
title: FAQ
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<a href="/">remoshock</a> &gt; <a href="/faq.html">FAQ</a>
<h1> Frequently asked Questions and answers</h1>


<h2 id="risks"><a href="#risks">⚠️ Risks</a></h2>

<h3 id="dangerous">Is playing with electricity dangerous?</h3>

<p> Yes, it is. Please see <a href="/warning.html">Warning</a>.


<h3 id="shouldi">Should I play with electricity?</h3>

<p> No, you should not. Please see <a href="/warning.html">Warning</a>.



<h2 id="about"><a href="#about">🔧 About the project</a></h2>

<h3 id="documentation">Where can I find documentation and source code?</h3>

<ul>
<li> Documentation: <a href="https://remoshock.github.io">https://remoshock.github.io</a>
<li> Source Code: <a href="https://github.com/remoshock/remoshock">https://github.com/remoshock/remoshock</a>
</ul>

<h3 id="reportbugs">How do I report bugs, feature requests and patches?</h3>

<p> Please use the GitHub issue tracker at
<a href="https://github.com/remoshock/remoshock">https://github.com/remoshock/remoshock</a>.


<h2 id="requirements"><a href="#requirements">✔️ Requirements</a></h2>

<h3 id="windows">Will remoshock work on Microsoft Windows?</h3>

<p> remoshock works on Linux only. Ubuntu 2024.04 is used for testing.


<h3 id="receivers">Which receivers are supported?</h3>

<ul>
<li> PAC collars (compatible with ATX and DTX remote, tested with ACX)
<li> Petrainer
<li> Patpet T150
<li> Wodondog "Dog Shock Collar"
</ul>

<p> Please see <a href="/receivers.html">Receivers</a> for details and photos.

<h3 id="sdr">What transmitter hardware do I need?</h3>

<p> You need a SDR (software defined radio) device, that
<ul>
<li> is able to transmit (most SDRs are receivers only)
<li> is able to operate on the required frequency (27.195 MHz for PAC)
<li> is supported by the software Universal Radio Hacker
</ul>

<p> According to Wikipedia both HackRF and LimeSDR fulfill those requirements.
HackRF is used for testing



<h2 id="troubleshooting"><a href="#troubleshooting">🔍 Troubleshooting</a></h2>

<h3 id="hardwareerrors">I am getting strange hardware error messages from my SDR transmitter</h3>

<p> Examples for error message:

<pre>
[CRITICAL::urh_cli.py::on_fatal_device_error_occurred] failed to start tx mode
[ERROR::Device.py::log_retcode] HackRF-SETUP
[ERROR::Device.py::log_retcode] HackRF-SETUP: HACKRF_ERROR_NOT_FOUND (-5)
[ERROR::Device.py::log_retcode] HackRF-SET_SAMPLE_RATE to 2M: HACKRF_ERROR_LIBUSB (-1000)
</pre>

<p> Please avoid USB hubs and USB extension cables, but connect your SDR
directly to your computer. At least USB 2 hubs are known to be too
slow to sustain the bit-stream.

<p> Please make sure that your computer is connected to the power network
(i. e. don't run your notebook on battery only). A throttled CPU
might be too slow to generate the bit-stream for the SDR.

<p> If you run Linux inside of a Virtual Machine on a slow computer, you
might experience the same performance problems. VirtualBox only supports
USB 1.x in the default installation. <p> Please see <a href="https://www.eltima.com/article/virtualbox-usb-passthrough">https://www.eltima.com/article/virtualbox-usb-passthrough/</a> on how to install and enable USB Passthrough support for VirtualBox.


<h3 id="udev">Access to HackRF only works as root</h3>

<p> Access to the HackRF hardware only works as root. remoshock crashes with
either a segmentation fault or the following error message:

<pre>
[ERROR::Device.py::log_retcode] HackRF-SETUP: HACKRF_ERROR_NOT_FOUND (-5)
</pre>

<p> The <code>hackrf_info</code> fails with the following error as a normal user:

<pre>
hackrf_open() failed: Access denied (insufficient permissions) (-1000)
</pre>

<p> In order to access the hardware as normal user, a udev rule is needed.
Please create the file /etc/udev/rules.d/53-hackrf.rules with the
content from <a href="https://raw.githubusercontent.com/mossmann/hackrf/master/host/libhackrf/53-hackrf.rules">https://raw.githubusercontent.com/mossmann/hackrf/master/host/libhackrf/53-hackrf.rules</a>

<pre>
	# grant access to user in group plugdev
	ATTR{idVendor}=="1d50", ATTR{idProduct}=="604b", SYMLINK+="hackrf-jawbreaker-%k", MODE="660", GROUP="plugdev"  
	ATTR{idVendor}=="1d50", ATTR{idProduct}=="6089", SYMLINK+="hackrf-one-%k", MODE="660", GROUP="plugdev"
	ATTR{idVendor}=="1d50", ATTR{idProduct}=="cc15", SYMLINK+="rad1o-%k", MODE="660", GROUP="plugdev"
	ATTR{idVendor}=="1fc9", ATTR{idProduct}=="000c", SYMLINK+="nxp-dfu-%k", MODE="660", GROUP="plugdev"
</pre>


<p> Furthermore please make sure that the user in the group plugdev.


<h3 id="verbose">HackRF stops working after inactivity</h3>

<p>The HackRF device seems to have problems with USB suspension. Please add the following lines to /etc/udev/rules.d/53-hackrf.rules</p>

<pre>
	# disable USB autosuspend for HackRF
	ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="1d50", ATTR{idProduct}=="604b", ATTR{power/autosuspend}="-1"
	ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="1d50", ATTR{idProduct}=="6089", ATTR{power/autosuspend}="-1"
	ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="1d50", ATTR{idProduct}=="cc15", ATTR{power/autosuspend}="-1"
	ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="1fc9", ATTR{idProduct}=="000c", ATTR{power/autosuspend}="-1"
</pre>

<h3 id="verbose">It is not working, why?</h3>

<p> Please add the parameter <code>--verbose</code>. It will enable debug logging.


<h3 id="virtualbox">I am in a VirtualBox VM and lsusb does not find my SDR transmitter</h3>

<p> Please see <a href="https://www.eltima.com/article/virtualbox-usb-passthrough">https://www.eltima.com/article/virtualbox-usb-passthrough/</a> on how to install and enable USB Passthrough support for VirtualBox.

<p> In short:
<ul>
<li> <code>apt install virtualbox-ext-pack</code>
<li> add yourself to the vboxuser group
<li> on the USB settings pages of the virutal machine select USB 3.0 controller
  and add a filter to allow access to the SDR device
</ul>

<h3 id="tested">Which setup is used for testing?</h3>

<p> I use Ubuntu 2024.04 with a HackRF transmitter, a PAC ACX collar and
a brandless Wodondog collar.