diff --git a/gr-jay/lib/squelch_impl.cc b/gr-jay/lib/squelch_impl.cc
new file mode 100644
index 0000000..c1a1b28
--- /dev/null
+++ b/gr-jay/lib/squelch_impl.cc
@@ -0,0 +1,131 @@
+/* -*- c++ -*- */
+/* 
+ * Copyright 2019 Jay Arrowfield.
+ * 
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ * 
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this software; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gnuradio/io_signature.h>
+#include <regex>
+#include "squelch_impl.h"
+
+namespace gr {
+  namespace jay {
+
+    squelch::sptr
+    squelch::make()
+    {
+      return gnuradio::get_initial_sptr
+        (new squelch_impl());
+    }
+
+    /*
+     * The private constructor
+     */
+	
+    squelch_impl::squelch_impl()
+      : gr::sync_block("squelch",
+              gr::io_signature::make(1, 1, sizeof(float)),
+              gr::io_signature::make(1, 1, sizeof(float)))
+	  , m_gain_target(1.0f)
+	  , m_gain(0.0f)
+    {
+		m_msg_port_in = pmt::mp("control");
+		message_port_register_in(m_msg_port_in);
+		set_msg_handler(m_msg_port_in, boost::bind(&squelch_impl::on_message, this, _1));		
+	}
+
+    /*
+     * Our virtual destructor.
+     */
+	squelch_impl::~squelch_impl()
+    {
+    }
+	
+	void squelch_impl::print_pair(pmt::pmt_t pair)
+	{
+		pmt::pmt_t key = pmt::car(pair);
+		pmt::pmt_t val = pmt::cdr(pair);
+		
+		if (pmt::symbol_to_string(key) == std::string("gain"))
+		{
+			float gain_dB = pmt::to_float(val) - 50.f;
+			m_gain_target = std::pow(10.f, gain_dB/10);
+			fprintf(stderr, "Set gain to %0.2f\n", m_gain_target);
+		}
+		if (pmt::is_integer(val))
+		{
+			fprintf(stderr, "[%s=%d]", pmt::symbol_to_string(key).c_str(), (int)pmt::to_long(val));
+		}
+		else if (pmt::is_real(val))
+		{
+			fprintf(stderr, "[%s=%f]", pmt::symbol_to_string(key).c_str(), pmt::to_float(val));
+		}
+		else if (pmt::is_bool(val))
+		{
+			fprintf(stderr, "[%s=%d]", pmt::symbol_to_string(key).c_str(), pmt::to_bool(val));
+		}
+		fprintf(stderr, "\n");
+	}
+		
+	void squelch_impl::on_message(pmt::pmt_t msg)
+	{
+		if (pmt::is_pair(msg))
+		{
+			print_pair(msg);
+		}
+		else if (pmt::is_dict(msg))
+		{
+			pmt::pmt_t items = pmt::dict_items(msg);
+			for (int i=0; i < pmt::length(items); i++)
+			{	
+				pmt::pmt_t pair = pmt::nth(i, items);
+				print_pair(pair);
+			}
+		}
+		else
+		{
+			fprintf(stderr, "%s\n", pmt::symbol_to_string(msg).c_str());
+		}
+	}
+
+	int
+    squelch_impl::work(int noutput_items,
+        gr_vector_const_void_star &input_items,
+        gr_vector_void_star &output_items)
+    {
+      const float *in = (const float *) input_items[0];
+      float *out = (float *) output_items[0];
+
+	  m_gain = 0.99f*m_gain + 0.01f*m_gain_target;
+	  
+      // Do <+signal processing+>
+	  for (int i=0; i < noutput_items; i++)
+	  {
+		  *(out++) = *(in++) * m_gain;
+	  }
+
+      // Tell runtime system how many output items we produced.
+      return noutput_items;
+    }
+
+  } /* namespace jay */
+} /* namespace gr */
+
diff --git a/gr-jay/lib/squelch_impl.h b/gr-jay/lib/squelch_impl.h
new file mode 100644
index 0000000..a1cb5ef
--- /dev/null
+++ b/gr-jay/lib/squelch_impl.h
@@ -0,0 +1,53 @@
+/* -*- c++ -*- */
+/* 
+ * Copyright 2019 Jay Arrowfield.
+ * 
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ * 
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this software; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef INCLUDED_JAY_SQUELCH_IMPL_H
+#define INCLUDED_JAY_SQUELCH_IMPL_H
+
+#include <jay/squelch.h>
+
+namespace gr {
+  namespace jay {
+
+    class squelch_impl : public squelch
+    {
+     private:
+      // Nothing to declare in this block.
+		pmt::pmt_t m_msg_port_in;
+		float m_gain_target;
+		float m_gain;
+		
+     public:
+      squelch_impl();
+      ~squelch_impl();
+	  void print_pair(pmt::pmt_t pair);
+	  void on_message(pmt::pmt_t msg);
+	  
+      // Where all the action really happens
+      int work(int noutput_items,
+         gr_vector_const_void_star &input_items,
+         gr_vector_void_star &output_items);
+    };
+
+  } // namespace jay
+} // namespace gr
+
+#endif /* INCLUDED_JAY_SQUELCH_IMPL_H */
+