<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Heathkit, like so many others at the time, used a bit of smoke and mirrors in the design of the display of the 104<div><br></div><div>In a nut shell, the display is nothing more than a frequency counter.</div><div><br></div><div>they use presets to 'preset' the display</div><div><br></div><div>pull or lift out all the boards except for the 'a' board and the 'b' board</div><div><br></div><div>put the band switch in the 3.5 mhz position</div><div><br></div><div>release the usb, lsb and cw switches. (all out)</div><div><br></div><div><br></div><div><br></div><div>power up the rig</div><div><br></div><div>you should see 6600.0</div><div><br></div><div>press usb and 6603.6</div><div><br></div><div>press lsb and 6606.4</div><div><br></div><div>and cw and 6604.3</div><div><br></div><div>if you don't then there's a counter problem. Start by verifying that the counter has a good solid +5 volts to it.</div><div><br></div><div>then power down, pull the counter board and gently remove the IC one at a time, then reset it into it's socket. Do just one IC at a time so you don't mess up where they went.</div><div><br></div><div>It's possible that you have a fubar driver chip on the display board, But I've found that they usually fail they cause missing segments or dual segments to light.</div><div><br></div><div>just sub out one of the chips on the display and see what happens</div><div><br></div><div><br></div><div>Let me know...</div><div><br></div><div>Mike, WB8VGE</div><div><br></div><div><br></div><div><br></div><div><br></div><div><br><div><div>On Oct 31, 2011, at 9:54 PM, Morris wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">
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<div><strong><span class="015385201-01112011"><font color="#0000ff">I've read that
the 11 volt regulation is often the culprit for display problems. I
haven't experienced it on mine yet. See what it reads, especially
when the failure occurs.</font></span></strong></div>
<div> </div>
<div><span class="015385201-01112011"><strong>GL,</strong></span></div><!-- Converted from text/rtf format --><p align="left"><font size="2" face="Arial">Morris</font> </p><p><em><font size="2"></font></em></p>
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<div dir="ltr" lang="en-us" class="OutlookMessageHeader" align="left"><font size="2" face="Tahoma">-----Original Message-----<br><b>From:</b>
<a href="mailto:heath-bounces@puck.nether.net">heath-bounces@puck.nether.net</a> [mailto:heath-bounces@puck.nether.net] <b>On
Behalf Of </b>KP2N<br><b>Sent:</b> Monday, October 31, 2011 9:05
AM<br><b>To:</b> <a href="mailto:heath@puck.nether.net">heath@puck.nether.net</a><br><b>Subject:</b> [Heath] SB104
question<br><br></font></div>
<div><font size="2" face="Arial"><span class="500545012-31102011">Our club was
donated a SB-104, SB-644A Remote VFO, and speaker/power supply
combo.</span></font></div>
<div><font size="2" face="Arial"><span class="500545012-31102011">After much
cleaning inside the radio works.</span></font></div>
<div><font size="2" face="Arial"><span class="500545012-31102011"></span></font> </div>
<div><font size="2" face="Arial"><span class="500545012-31102011">The newest problem
is the frequency display. The gas discharge tubes seem to be
ok.</span></font></div>
<div><font size="2" face="Arial"><span class="500545012-31102011">When in the 20
meter switch position the display reads 15255 instead of 14255. The rig
is</span></font></div>
<div><font size="2" face="Arial"><span class="500545012-31102011">receiving on 14255
so there is a display problem. 15 meters is reading correctly but 10
meters</span></font></div>
<div><font size="2" face="Arial"><span class="500545012-31102011">is reading 1 MHz
high 29400 instead of 28450. 80 and 40 meters seem to read
correctly.</span></font></div>
<div><font size="2" face="Arial"><span class="500545012-31102011"></span></font> </div>
<div><font size="2" face="Arial"><span class="500545012-31102011">I am sure this
question has been asked years ago but we just received this radio and it
has</span></font></div>
<div><font size="2" face="Arial"><span class="500545012-31102011">a lot of history
behind it. Would like to get it operating correctly.</span></font></div>
<div><font size="2" face="Arial"><span class="500545012-31102011"></span></font> </div>
<div><font size="2" face="Arial"><span class="500545012-31102011">If you can
indicate where to start to look it would be much
appreciated.</span></font></div>
<div><font size="2" face="Arial"><span class="500545012-31102011"></span></font> </div>
<div><font size="2" face="Arial"><span class="500545012-31102011">73 Ron
KP2N</span></font></div>
<div><font size="2" face="Arial"><span class="500545012-31102011">St. Pete,
FL</span></font></div>
<div><font size="2" face="Arial"><span class="500545012-31102011"></span></font> </div></blockquote></div>
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