<html><head></head><body><div style="color:#000; background-color:#fff; font-family:Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:13px"><div id="yui_3_16_0_ym19_1_1485971635447_35067">Sandy,</div><div id="yui_3_16_0_ym19_1_1485971635447_34999" dir="ltr">Those switch banks are notorious for the sliding contacts breaking inside the switch. They have a sliding body that holds metallic contacts which move when the handle moves. If the contact breaks, then it is possible to bypass the break-before-make function of the switch. One side of the switch is switching the ALC line from what I can tell. The other side seems to part of the CW drive level. So yes, either of those could give you a big surge during the switch. These switches also get very noisy because the contacts are silver plated. when the silver tarnishes, it produces some abrasive action that breaks through the plating to the base metal. The only fix is to replace the switch.</div><div dir="ltr" id="yui_3_16_0_ym19_1_1485971635447_38923">Al</div><div dir="ltr" id="yui_3_16_0_ym19_1_1485971635447_38963">WB9UVJ<br></div><div id="yui_3_16_0_ym19_1_1485971635447_34949"><span></span></div> <div class="qtdSeparateBR"><br><br></div><div class="yahoo_quoted" style="display: block;"> <div style="font-family: Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 13px;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;"> <div dir="ltr"><font size="2" face="Arial"> On Monday, January 30, 2017 11:00 AM, "heath-request@puck.nether.net" <heath-request@puck.nether.net> wrote:<br></font></div> <br><br> <div class="y_msg_container">Send Heath mailing list submissions to<br> <a ymailto="mailto:heath@puck.nether.net" href="mailto:heath@puck.nether.net">heath@puck.nether.net</a><br><br>To subscribe or unsubscribe via the World Wide Web, visit<br> <a href="https://puck.nether.net/mailman/listinfo/heath" target="_blank">https://puck.nether.net/mailman/listinfo/heath</a><br>or, via email, send a message with subject or body 'help' to<br> <a ymailto="mailto:heath-request@puck.nether.net" href="mailto:heath-request@puck.nether.net">heath-request@puck.nether.net</a><br><br>You can reach the person managing the list at<br> <a ymailto="mailto:heath-owner@puck.nether.net" href="mailto:heath-owner@puck.nether.net">heath-owner@puck.nether.net</a><br><br>When replying, please edit your Subject line so it is more specific<br>than "Re: Contents of Heath digest..."<br><br><br>Today's Topics:<br><br> 1. SB-104A PS problem (Alexander N. Gerli)<br><br><br>----------------------------------------------------------------------<br><br>Message: 1<br>Date: Sun, 29 Jan 2017 15:33:28 +0000<br>From: "Alexander N. Gerli" <<a ymailto="mailto:ac1wye@gmail.com" href="mailto:ac1wye@gmail.com">ac1wye@gmail.com</a>><br>To: "<a ymailto="mailto:heath@puck.nether.net" href="mailto:heath@puck.nether.net">heath@puck.nether.net</a>" <<a ymailto="mailto:heath@puck.nether.net" href="mailto:heath@puck.nether.net">heath@puck.nether.net</a>>,<br> "<a ymailto="mailto:heathkit@mailman.qth.net" href="mailto:heathkit@mailman.qth.net">heathkit@mailman.qth.net</a>" <<a ymailto="mailto:heathkit@mailman.qth.net" href="mailto:heathkit@mailman.qth.net">heathkit@mailman.qth.net</a>><br>Subject: [Heath] SB-104A PS problem<br>Message-ID:<br> <CACs0R22vxqrXHSMm+QYVNZMzpEc4ATq36utf=aOFV==<a ymailto="mailto:rVnK9uA@mail.gmail.com" href="mailto:rVnK9uA@mail.gmail.com">rVnK9uA@mail.gmail.com</a>><br>Content-Type: text/plain; charset="utf-8"<br><br>Hi, friends! Sometimes, when in TUNE and HI POWER (always start out with<br>the Mic Gain at Zero), when I release the TUNE button, the 20A fuse will<br>blow, sometimes it doesn't. I suspect some sort of instantaneous, transient<br>current spike blows the fuse? Although the PS Manual does not call for it,<br>should I try a SloBlo fuse in the 13.8Vdc line to handle such a spike?<br><br>73, Sandy AC1Y<br>-- <br>Sent from Sandy's Gmail Mobile<br>-------------- next part --------------<br>An HTML attachment was scrubbed...<br>URL: <<a href="https://puck.nether.net/pipermail/heath/attachments/20170129/3a66baad/attachment-0001.html" target="_blank">https://puck.nether.net/pipermail/heath/attachments/20170129/3a66baad/attachment-0001.html</a>><br><br>------------------------------<br><br>Subject: Digest Footer<br><br>_______________________________________________<br>Heath mailing list<br><a ymailto="mailto:Heath@puck.nether.net" href="mailto:Heath@puck.nether.net">Heath@puck.nether.net</a><br><a href="https://puck.nether.net/mailman/listinfo/heath" target="_blank">https://puck.nether.net/mailman/listinfo/heath</a><br><br><br>------------------------------<br><br>End of Heath Digest, Vol 73, Issue 10<br>*************************************<br><br><br></div> </div> </div> </div></div></body></html>