<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue-Light, Helvetica Neue Light, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px"><div id="yui_3_16_0_1_1419345611230_2919" dir="ltr"><span id="yui_3_16_0_1_1419345611230_3007">One problem with the AM filter for the SB-301 and SB-303 is that it is WAY too narrow for decent AM operation. The AM filter for the SB-300 was 3.5 kHz wide and the AM filter for the SB-301 and SB-303 was 3.75 kHz wide. That is just way too narrow for good sounding AM audio.</span></div><div id="yui_3_16_0_1_1419345611230_2919" dir="ltr"><span><br></span></div><div id="yui_3_16_0_1_1419345611230_2919" dir="ltr"><span id="yui_3_16_0_1_1419345611230_3447">The AM filter that was supplied with the SWL versions, SB-310 and SB-313, is 5.0 kHz wide and the audio does "sound" better than with the 3.5 kHz or 3.75 kHz filters. However, even the 5.0 kHz filter constrains the audio.</span></div><div id="yui_3_16_0_1_1419345611230_2919" dir="ltr"><span><br></span></div><div id="yui_3_16_0_1_1419345611230_2919" dir="ltr"><span id="yui_3_16_0_1_1419345611230_3754">One can get somewhat better sounding AM audio by tuning to one side and, basically, receiving only one side band.</span></div><div></div><div id="yui_3_16_0_1_1419345611230_2903"> </div><div id="yui_3_16_0_1_1419345611230_2905"><div id="yui_3_16_0_1_1419345611230_2904">Glen, K9STH
<br>
<br>Website: http://k9sth.net</div></div><br> <div style="font-family: HelveticaNeue-Light, Helvetica Neue Light, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1419345611230_2908"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1419345611230_2907"> <div dir="ltr" id="yui_3_16_0_1_1419345611230_2906"> <hr size="1" id="yui_3_16_0_1_1419345611230_3755"> <font size="2" face="Arial" id="yui_3_16_0_1_1419345611230_2918"> <b><span style="font-weight:bold;">From:</span></b> Guy Giacopuzzi <gggdds@js-net.com><br> <b><span style="font-weight: bold;">To:</span></b> heath@puck.nether.net <br> <b id="yui_3_16_0_1_1419345611230_2917"><span style="font-weight: bold;" id="yui_3_16_0_1_1419345611230_2916">Sent:</span></b> Monday, December 22, 2014 5:59 PM<br> <b><span style="font-weight: bold;">Subject:</span></b> Re: [Heath] Fw: AM Crystal filter for SB-303<br> </font> </div> <div class="y_msg_container" id="yui_3_16_0_1_1419345611230_2911"><br><div id="yiv3035911086"><div id="yui_3_16_0_1_1419345611230_2910">
Only the AM section is bad? To confirm it's the filter, it should
only be the am section; after that, I would look at the am detector
circuit...I've never heard of a xtal filter "going bad"...<br clear="none"></div></div></div> </div> </div> </div></body></html>