<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;"><DIV>Thoughts</DIV>
<DIV>1. I wonder if 1394 interface would be worth doing giving more horsepower than USB2. </DIV>
<DIV>2.The idea of a transceiver on one board fits right in with my present project interfacing to Penny and Mercury working my way up to 1.5 KW. </DIV>
<DIV>3. This would leave atlas for a VNA or other test equipment options.</DIV>
<DIV> </DIV>
<DIV>Thor,</DIV>
<DIV>I have been playing with PDM for 25 years and glad to share thoughts with any designers. </DIV>
<DIV>A push pull modulator is a bit complicated and a bit tricky near zero modulation. It is pretty easy to build a floating switch with an opto, some diodes, a good mos driver and n channel FETs. many of us are doing this with a 1:1 isolation at 130 volts. Just as easy at 40 volts. All you need is a floating charge pump to hold the fets on. I have a friend sells driver board kits that will easily do the legal limit. Input is digital level. This circuit is easy to duplicate. </DIV>
<DIV>frank </DIV></td></tr></table>