<html><head></head><body><div style="color:#000; background-color:#fff; font-family:Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px"><div id="yui_3_16_0_1_1490638376872_4881"><span id="yui_3_16_0_1_1490638376872_4956">Methinks a typo! The cathode resistors in the SB-102 are 10-ohms and not 20-ohms.</span></div><div id="yui_3_16_0_1_1490638376872_4881"><span><br></span></div><div id="yui_3_16_0_1_1490638376872_4881"><span><br></span></div><div id="yui_3_16_0_1_1490638376872_4881"><span><br></span></div><div id="yui_3_16_0_1_1490638376872_4881" dir="ltr"><span id="yui_3_16_0_1_1490638376872_4957">As for the "S" meter reading: You need to check the sensitivity of the receiver portion and the "S" meter reading using a signal generator with an accurate attenuator. A signal level of 50-microvolts is the EIA standard for S-9. Many of the Japanese units have "S" meters that are definitely not calibrated to the standard and also are no where being accurate in the "dB over" range.</span></div><div id="yui_3_16_0_1_1490638376872_4881" dir="ltr"><span><br></span></div><div id="yui_3_16_0_1_1490638376872_4881" dir="ltr"><span><br></span></div><div id="yui_3_16_0_1_1490638376872_4881" dir="ltr"><span><br></span></div><div id="yui_3_16_0_1_1490638376872_4881" dir="ltr"><span id="yui_3_16_0_1_1490638376872_5256">The Japanese manufacturers got into a "war" a number of years back with each claiming that their receivers were more sensitive than the other manufacturers. What they actually did was to reduce the signal strength needed for S-9 and eliminate a true dB over reading. As such, those units read considerably higher for the same signal level than those S"S meters calibrated by the ol EIA standard.</span></div><div id="yui_3_16_0_1_1490638376872_4881" dir="ltr"><span><br></span></div><div id="yui_3_16_0_1_1490638376872_4881" dir="ltr"><span><br></span></div><div id="yui_3_16_0_1_1490638376872_4881" dir="ltr"><span><br></span></div><div id="yui_3_16_0_1_1490638376872_4881" dir="ltr"><span id="yui_3_16_0_1_1490638376872_5324">All my "S" meters are calibrated for S-9 = 50-microvolts and I have an above average antenna array. Often, signals do not even reach S-9 and it takes a local to achieve a 20 dB over reading. An operator, who lives 5-blocks from me and who runs a Heath SB-200 amplifier, often doesn't even make it to a 40 dB over level. But, way too many operators these days are used to getting a minimum of S-9 and often "20 dB over" to even as much as "60 dB" over and are insulted if you give then less than an S-9 reading. Therefore, I generally resort to the system that we used when the majority of receivers did not have an "S" meter. If the station is in the clear and strng enough to easily copy, there are an S-9.</span></div><div id="yui_3_16_0_1_1490638376872_4881" dir="ltr"><span><br></span></div><div id="yui_3_16_0_1_1490638376872_4881" dir="ltr"><span><br></span></div><div></div><div id="yui_3_16_0_1_1490638376872_4994"> </div><div class="signature" id="yui_3_16_0_1_1490638376872_5007">Glen, K9STH absite: http://k9sth.net</div><div class="qtdSeparateBR" id="yui_3_16_0_1_1490638376872_4977"><br><br></div><div class="yahoo_quoted" id="yui_3_16_0_1_1490638376872_4981" style="display: block;"> <div style="font-family: Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1490638376872_4980"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_1_1490638376872_4979"> <div dir="ltr" id="yui_3_16_0_1_1490638376872_4978"> <font size="2" face="Arial" id="yui_3_16_0_1_1490638376872_4982"> <hr size="1"> <b><span style="font-weight:bold;">From:</span></b> Joseph Smalley via Heath <heath@puck.nether.net><br> <b><span style="font-weight: bold;">To:</span></b> "heath@puck.nether.net" <heath@puck.nether.net> <br> <b><span style="font-weight: bold;">Sent:</span></b> Monday, March 27, 2017 12:54 PM<br> <b><span style="font-weight: bold;">Subject:</span></b> [Heath] Fw: SB-102 S-Meter operation<br> </font> </div> <div class="y_msg_container" id="yui_3_16_0_1_1490638376872_4983"><br><div id="yiv7414925944"><div id="yui_3_16_0_1_1490638376872_4985"><div style="color:#000;background-color:#fff;font-family:Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:13px;" id="yui_3_16_0_1_1490638376872_4984"><div id="yiv7414925944yui_3_16_0_1_1490632681360_5453"><span></span></div><div class="yiv7414925944qtdSeparateBR" id="yiv7414925944yui_3_16_0_1_1490632681360_5452"><br><br></div> <div class="yiv7414925944yahoo_quoted" id="yiv7414925944yui_3_16_0_1_1490632681360_5449" style="display:block;"> <div style="font-family:Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:13px;" id="yiv7414925944yui_3_16_0_1_1490632681360_5448"> <div style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;" id="yiv7414925944yui_3_16_0_1_1490632681360_5447"> <div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490632681360_5450"><font id="yiv7414925944yui_3_16_0_1_1490632681360_5451" size="2" face="Arial"> On Sunday, March 26, 2017 10:54 PM, Joseph Smalley <mymodecw-hamitup@yahoo.com> wrote:<br></font></div> <br><br> <div class="yiv7414925944y_msg_container" id="yiv7414925944yui_3_16_0_1_1490632681360_5446"><div id="yiv7414925944"><div id="yiv7414925944yui_3_16_0_1_1490632681360_5445"><div style="color:#000;background-color:#fff;font-family:Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:13px;" id="yiv7414925944yui_3_16_0_1_1490632681360_5444"><div id="yiv7414925944yui_3_16_0_1_1490579132159_31711"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31733"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31736" clear="none"></div><div id="yiv7414925944yui_3_16_0_1_1490579132159_31738"> Hello to the group. I still use my SB-102 that I built in 1972, I have two issues I want to fix.</div><div id="yiv7414925944yui_3_16_0_1_1490579132159_31740"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31743" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31745">Number ONE is the poor operation of the S-meter very rarely does the S-meter give a good reading</div><div id="yiv7414925944yui_3_16_0_1_1490579132159_31747"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31750" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31752">even on real strong signals. A fellow ham close by gets a pinned needle on my TS-530sp on the</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31754"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31757" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31759">Sb-102 it will be S9. Most stations I work have a loud signal but low reading on the S-meter. Never S9<br id="yiv7414925944yui_3_16_0_1_1490579132159_31762" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31764"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31767" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31768"> I have put new 6AU6 I.F. amplifier tubes in the radio no help. Replaced the Product detector/AVC tube, no help</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31770"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31773" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31775">Any ideas will be appreciated.</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31777"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31780" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31782">Number TWO sometimes the resting (idling) plate current will increase above the set value of 50 MA, this happens</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31784"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31787" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31789">when I get long winded CW only here. <br id="yiv7414925944yui_3_16_0_1_1490579132159_31792" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31794"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31797" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31799">I recently repaired a SB-100 for a friend that had an excessive plate current reading which turned out to be</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31801"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31804" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31806">the cathode resistors on the final amplifiers.This is not what I am experiencing. The reading was 3 ohms for the <br id="yiv7414925944yui_3_16_0_1_1490579132159_31809" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31811"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31814" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31816">six 20 OHM resistors in parallel, when I replaced the resistors the reading went to 1.6 OHMS which I measured</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31818"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31821" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31823">on another properly working SB-102.</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31825"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31828" clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31830">Any info will be appreciated.</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_31832"><br id="yiv7414925944yui_3_16_0_1_1490579132159_31835" clear="none"></div>73 Joe WA3CKA <div class="yiv7414925944qtdSeparateBR" id="yui_3_16_0_1_1490638376872_5587"><br clear="none"><br clear="none"></div><div class="yiv7414925944yahoo_quoted" style="display:block;" id="yiv7414925944yui_3_16_0_1_1490632681360_5600"> <div style="font-family:Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:13px;" id="yiv7414925944yui_3_16_0_1_1490632681360_5599"> <div style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;" id="yiv7414925944yui_3_16_0_1_1490632681360_5598"> <div class="yiv7414925944yqt3593709739" id="yiv7414925944yqtfd52302"><div class="yiv7414925944y_msg_container" id="yiv7414925944yui_3_16_0_1_1490632681360_5597"><br><div id="yiv7414925944"><div id="yiv7414925944yui_3_16_0_1_1490632681360_5596"><div style="color:#000;background-color:#fff;font-family:Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:13px;" id="yiv7414925944yui_3_16_0_1_1490632681360_5595"><div id="yiv7414925944yui_3_16_0_1_1490579132159_8818"> Hello to the group. I still use my SB-102 that I built in 1972, I have two issues I want to fix.</div><div id="yiv7414925944yui_3_16_0_1_1490579132159_9054"><br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9052">Number ONE is the poor operation of the S-meter very rarely does the S-meter give a good reading</div><div id="yiv7414925944yui_3_16_0_1_1490579132159_9056"><br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_8962">even on real strong signals. A fellow ham close by gets a pinned needle on my TS-530sp on the</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9058"><br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9051">Sb-102 it will be S9. Most stations I work have a loud signal but low reading on the S-meter. Never S9<br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9102"><br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9050"> I have put new 6AU6 I.F. amplifier tubes in the radio no help. Replaced the Product detector/AVC tube, no help</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9118"><br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9162">Any ideas will be appreciated.</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9163"><br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9164">Number TWO sometimes the resting (idling) plate current will increase above the set value of 50 MA, this happens</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9172"><br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9173">when I get long winded CW only here. <br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9188"><br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9189">I recently repaired a SB-100 for a friend that had an excessive plate current reading which turned out to be</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9240"><br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9241">the cathode resistors on the final amplifiers.This is not what I am experiencing. The reading was 3 ohms for the <br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9264"><br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9319">six 20 OHM resistors in parallel, when I replaced the resistors the reading went to 1.6 OHMS which I measured</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9320"><br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9321">on another properly working SB-102.</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9369"><br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9384">Any info will be appreciated.</div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9431"><br clear="none"></div><div dir="ltr" id="yiv7414925944yui_3_16_0_1_1490579132159_9432"><br></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div> </div> </div> </div></div></body></html>