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    I guess there's a few other ways, yes, to do a matched pair with
    integral heater.. but the idea here was really a drop-in clone for
    the ua726<br>
    (not that I actually have any personal need for them - just aware of
    the ridiculous scarcity pricing that keeps cropping up - and figured
    it looked do-able - ie. fun project potential, not that I really
    need more projects..)<br>
    Also MAT04 now says obsolete.. THAT300 series would be a fine
    replacement in that case.<br>
    Ta, Tom<br>
    <br>
    <div class="moz-cite-prefix">On 09/09/2015 18:36, Rick Jansen wrote:<br>
    </div>
    <blockquote
      cite="mid:32B4F5E0-90B7-451B-A15F-22D194D8EC96@xs4all.nl"
      type="cite">
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      <div>Use a mat04.. Two transistors as the matched pair, one as
        heater, one as sensor. One external transistor as a clamp. See
        the circuit at the bottom of <a moz-do-not-send="true"
          href="http://dropmix.xs4all.nl/rick/Emusic/Moog/moogvcf_schematic.gif">http://dropmix.xs4all.nl/rick/Emusic/Moog/moogvcf_schematic.gif</a></div>
      <div><br>
      </div>
      <div>Rick</div>
      <div><br>
        On 09 Sep 2015, at 15:19, Tom Bugs <<a moz-do-not-send="true"
          href="mailto:admin@bugbrand.co.uk">admin@bugbrand.co.uk</a>>
        wrote:<br>
        <br>
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          I wondered before why no-one seems to have done a clone of the
          ua726.<br>
          <br>
          Doesn't *SEEM* all that complex?!<br>
          A nice matched pair (eg LS318) is the main core.<br>
          6 transistors (I presume general purpose?), 2 x 6V2 zeners and
          6 standard resistors.. - those parts being for the heating
          element.<br>
          <br>
          Get the pin placement right, encapsulate it in goo.. <br>
          <br>
          What am I wrong on? <br>
          <br>
          [I don't want to fully take on such a project, though could
          potentially do a design up for initial testing with a view to
          someone running a production in a friendly open-source-ish
          manner]<br>
          <br>
          Tom<br>
          <br>
          <br>
          <br>
          <div class="moz-cite-prefix">On 09/09/2015 14:00, . . wrote:<br>
          </div>
          <blockquote
cite="mid:CAMUkUjRzSoT+=mWxbJtjq1QJWBSyX4OHQ+Uxm=NX7PTFLVV+-g@mail.gmail.com"
            type="cite">
            <div dir="ltr">Wow don't pay 90$ for that!
              <div><br>
              </div>
              <div>I've bought a few fakes some years ago for about
                10-15$ each iirc  They worked according to my tech at
                the time.   It's hard to say if they perform exactly the
                same, I ended up putting in a real one in just to be
                sure.</div>
              <div><br>
              </div>
              <div><br>
              </div>
            </div>
            <div class="gmail_extra"><br>
              <div class="gmail_quote">On Wed, Sep 9, 2015 at 7:42 AM,
                Synth Parts <span dir="ltr"><<a
                    moz-do-not-send="true"
                    href="mailto:synthpartsdotcom@gmail.com"
                    target="_blank"><a class="moz-txt-link-abbreviated" href="mailto:synthpartsdotcom@gmail.com">synthpartsdotcom@gmail.com</a></a>></span>
                wrote:<br>
                <blockquote class="gmail_quote" style="margin:0 0 0
                  .8ex;border-left:1px #ccc solid;padding-left:1ex">
                  <div dir="ltr">Also very suspicious is the pic of the
                    one with the year 2000 date code and that there's no
                    pics showing the pins (they were gold on the real
                    ones)...
                    <div><br>
                    </div>
                    <div>Doug </div>
                    <div><a moz-do-not-send="true"
                        href="http://synthparts.com" target="_blank">synthparts.com</a></div>
                  </div>
                  <div class="HOEnZb">
                    <div class="h5">
                      <div class="gmail_extra"><br>
                        <div class="gmail_quote">On Wed, Sep 9, 2015 at
                          4:34 AM, Kenny Balys <span dir="ltr"><<a
                              moz-do-not-send="true"
                              class="moz-txt-link-abbreviated"
                              href="mailto:kenny@beatkamp.com"><a class="moz-txt-link-abbreviated" href="mailto:kenny@beatkamp.com">kenny@beatkamp.com</a></a>></span>
                          wrote:<br>
                          <blockquote class="gmail_quote"
                            style="margin:0 0 0 .8ex;border-left:1px
                            #ccc solid;padding-left:1ex"><br>
                            I doubt that these were ever shipped to, or
                            made in China so I would look elsewhere. Its
                            hard to imagine that in the 1970's,
                            Fairchild, in the height of the cold war,
                            would be manufacturing vital components such
                            as these in China.<br>
                            <br>
                            On 09-09-15 09:29 , Synth Parts wrote:<br>
                            <blockquote class="gmail_quote"
                              style="margin:0 0 0 .8ex;border-left:1px
                              #ccc solid;padding-left:1ex"> I recognize
                              that sellers name as one selling fake
                              SSM2040s a while back.<br>
                              Lots of feedback regarding fake parts -<br>
                              <br>
                              <a moz-do-not-send="true"
href="http://feedback.ebay.com/ws/eBayISAPI.dll?ViewFeedback2&userid=polida2008&iid=400613597638&de=off&items=25&which=negative&interval=365&_trkparms=negative_365"
                                rel="noreferrer" target="_blank">http://feedback.ebay.com/ws/eBayISAPI.dll?ViewFeedback2&userid=polida2008&iid=400613597638&de=off&items=25&which=negative&interval=365&_trkparms=negative_365</a><br>
                              <br>
                              Doug<br>
                              <a moz-do-not-send="true"
                                href="http://synthparts.com"
                                rel="noreferrer" target="_blank">synthparts.com</a><br>
                              <br>
                              On Tue, Sep 8, 2015 at 10:30 PM, Larry Dee
                              <<a moz-do-not-send="true"
                                class="moz-txt-link-abbreviated"
                                href="mailto:mintlake@bctonline.com">mintlake@bctonline.com</a>>

                              wrote:<br>
                              <br>
                              <blockquote class="gmail_quote"
                                style="margin:0 0 0 .8ex;border-left:1px
                                #ccc solid;padding-left:1ex"> Is this
                                the real thing?<br>
                                <br>
                                <br>
                                <a moz-do-not-send="true"
href="http://www.ebay.com/itm/1PCS-CONTROLLED-DIFFERENTIAL-PREAMPLIFIER-IC-FAIRCHILD-TO-100-CAN-10-UA726HC-/400613597638?hash=item5d466e61c6"
                                  rel="noreferrer" target="_blank">http://www.ebay.com/itm/1PCS-CONTROLLED-DIFFERENTIAL-PREAMPLIFIER-IC-FAIRCHILD-TO-100-CAN-10-UA726HC-/400613597638?hash=item5d466e61c6</a><br>
                                <br>
                                <br>
                                <br>
                                I’m so burned out on this issue –
                                sheeeesh for $90 it better be NOS.<br>
                                Tried searching the AH archives for
                                recent content on this subject but did<br>
                                not get anywhere.  Sorry to be
                                redundant, but what is the latest word
                                on<br>
                                this part?<br>
                                <br>
                              </blockquote>
                              <br>
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          <br>
          <pre class="moz-signature" cols="72">-- 
BugBrand LTD
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        <div><span>_______________________________________________</span><br>
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      </blockquote>
    </blockquote>
    <br>
    <pre class="moz-signature" cols="72">-- 
BugBrand LTD
UK company No. 07199808
VAT No. GB 988 2629 57
1 Ninetree Hill
BRISTOL BS1 3SB
United Kingdom
<a class="moz-txt-link-abbreviated" href="http://www.bugbrand.co.uk">www.bugbrand.co.uk</a></pre>
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