<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body style="overflow-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;"><div><br></div><div style="display: block;"><div style="-webkit-user-select: all; -webkit-user-drag: element; display: inline-block;" class="apple-rich-link" draggable="true" role="link" data-url="https://www.lavarand.org/"><a style="border-radius:10px;font-family:-apple-system, Helvetica, Arial, sans-serif;display:block;-webkit-user-select:none;width:300px;user-select:none;-webkit-user-modify:read-only;user-modify:read-only;overflow:hidden;text-decoration:none;" class="lp-rich-link" rel="nofollow" href="https://www.lavarand.org/" dir="ltr" role="button" draggable="false" width="300"><table style="table-layout:fixed;border-collapse:collapse;width:300px;background-color:#B28989;font-family:-apple-system, Helvetica, Arial, sans-serif;" class="lp-rich-link-emailBaseTable" cellpadding="0" cellspacing="0" border="0" width="300"><tbody><tr><td vertical-align="center" align="center"><img style="width:300px;filter:brightness(0.97);height:159px;" width="300" height="159" draggable="false" class="lp-rich-link-mediaImage" alt="logo-big.gif" src="cid:95A7B99F-9216-470E-8FA8-55EA9DEB57E4"></td></tr><tr><td vertical-align="center"><table bgcolor="#B28989" cellpadding="0" cellspacing="0" width="300" style="table-layout:fixed;font-family:-apple-system, Helvetica, Arial, sans-serif;background-color:rgba(178, 137, 137, 1);-apple-color-filter:initial;" class="lp-rich-link-captionBar"><tbody><tr><td style="padding:8px 0px 8px 0px;" class="lp-rich-link-captionBar-textStackItem"><div style="max-width:100%;margin:0px 16px 0px 16px;overflow:hidden;" class="lp-rich-link-captionBar-textStack"><div style="word-wrap:break-word;font-weight:500;font-size:12px;overflow:hidden;text-overflow:ellipsis;text-align:left;" class="lp-rich-link-captionBar-textStack-topCaption-leading"><a rel="nofollow" href="https://www.lavarand.org/" style="text-decoration: none" draggable="false"><font color="#FFFFFF" style="color: rgba(255, 255, 255, 0.847059);">LavaRnd</font></a></div><div style="word-wrap:break-word;font-weight:400;font-size:11px;overflow:hidden;text-overflow:ellipsis;text-align:left;" class="lp-rich-link-captionBar-textStack-bottomCaption-leading"><a rel="nofollow" href="https://www.lavarand.org/" style="text-decoration: none" draggable="false"><font color="#FFFFFF" style="color: rgba(255, 255, 255, 0.54902);">lavarand.org</font></a></div></div></td></tr></tbody></table></td></tr></tbody></table></a></div></div><div><br></div><div><br></div><div><br></div><br id="lineBreakAtBeginningOfMessage"><div><br><blockquote type="cite"><div>On Dec 14, 2025, at 23:28, Hugh Blemings <hugh@blemings.org> wrote:</div><br class="Apple-interchange-newline"><div><meta charset="UTF-8"><div style="margin-top: 0px; margin-bottom: 0px; caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;">Hi All,</div><div style="margin-top: 0px; margin-bottom: 0px; caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><br>I'm reminded of "ChaosKey" a design that Keith Packard and Bdale Garbee put together to create entropy for the random number generator in the Linux kernel. It's based off a pair of transistors biased up at something like 20V and fully open source. <span class="Apple-converted-space"> </span><a class="moz-txt-link-freetext" href="https://altusmetrum.org/ChaosKey/">https://altusmetrum.org/ChaosKey/</a></div><div style="margin-top: 0px; margin-bottom: 0px; caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><br></div><div style="margin-top: 0px; margin-bottom: 0px; caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;">Might be of interest?<br><br></div><div style="margin-top: 0px; margin-bottom: 0px; caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;">Cheers,<br>Hugh</div><div style="margin-top: 0px; margin-bottom: 0px; caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><br></div><div style="margin-top: 0px; margin-bottom: 0px; caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><br></div><div class="moz-cite-prefix" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;">On 15/12/2025 07:38, Mike Bryant wrote:<br></div><blockquote type="cite" cite="mid:CWLP265MB7132BB62D7C982EE6D01F746DBACA@CWLP265MB7132.GBRP265.PROD.OUTLOOK.COM" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><div class="elementToProof" style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt;">I think you'll find the LM194 and its clones are the only monolithic ones left now. There were others a few years ago but most others are now two very well matched but separate die in the same package.</div><hr tabindex="-1" style="display: inline-block; width: 1222.046875px;"><div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size: 11pt;"><b>From:</b><span class="Apple-converted-space"> </span>Synth-diy<span class="Apple-converted-space"> </span><a class="moz-txt-link-rfc2396E" href="mailto:synth-diy-bounces@synth-diy.org"><synth-diy-bounces@synth-diy.org></a><span class="Apple-converted-space"> </span>on behalf of Ian Fritz via Synth-diy<span class="Apple-converted-space"> </span><a class="moz-txt-link-rfc2396E" href="mailto:synth-diy@synth-diy.org"><synth-diy@synth-diy.org></a><br><b>Sent:</b><span class="Apple-converted-space"> </span>13 December 2025 19:53<br><b>To:</b><span class="Apple-converted-space"> </span>Gordonjcp<span class="Apple-converted-space"> </span><a class="moz-txt-link-rfc2396E" href="mailto:gordonjcp@gjcp.net"><gordonjcp@gjcp.net></a><br><b>Cc:</b><span class="Apple-converted-space"> </span><a class="moz-txt-link-abbreviated" href="mailto:synth-diy@synth-diy.org">synth-diy@synth-diy.org</a><span class="Apple-converted-space"> </span><a class="moz-txt-link-rfc2396E" href="mailto:synth-diy@synth-diy.org"><synth-diy@synth-diy.org></a><br><b>Subject:</b><span class="Apple-converted-space"> </span>Re: [sdiy] SMT transistor for white noise?</font><div> </div></div><div class="BodyFragment"><font size="2"><span style="font-size: 11pt;"><div class="PlainText">Do they have these in monolithic pair packages?<br><br>Ian<br><br>> On Dec 13, 2025, at 12:27 PM, Gordonjcp<span class="Apple-converted-space"> </span><a class="moz-txt-link-rfc2396E" href="mailto:gordonjcp@gjcp.net"><gordonjcp@gjcp.net></a><span class="Apple-converted-space"> </span>wrote:<br>><span class="Apple-converted-space"> </span><br>> On Sat, Dec 13, 2025 at 11:11:54AM +0000, Mike Bryant wrote:<br>>> Too true 🙂 A large percentage of the world's small signal transistors now come from a huge fab in Chongqing and they just brand them to whatever their client wants.<br>>><span class="Apple-converted-space"> </span><br>><span class="Apple-converted-space"> </span><br>> Many years ago I bought a bag of something like 500 of the cheapest Chinesiest BC548-wannabes from Some Dude In Shenzen On eBay, expecting to maybe hand-match a couple of sets of a dozen reasonably close ones for filters.<br>><span class="Apple-converted-space"> </span><br>> Nope.<br>><span class="Apple-converted-space"> </span><br>> Any two you pulled out of the bag at random would have the same Vbe down to *microvolts*.<br>><span class="Apple-converted-space"> </span><br>> So that was a quicker evening than I anticipated.<br>><span class="Apple-converted-space"> </span><br>> --<br>> Gordonjcp<br>><span class="Apple-converted-space"> </span><br>> ________________________________________________________<br>> This is the Synth-diy mailing list<br>> Submit email to:<span class="Apple-converted-space"> </span><a class="moz-txt-link-abbreviated" href="mailto:Synth-diy@synth-diy.org">Synth-diy@synth-diy.org</a><br>> View archive at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/pipermail/synth-diy/" moz-do-not-send="true" class="moz-txt-link-freetext">https://synth-diy.org/pipermail/synth-diy/</a><br>> Check your settings at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/mailman/listinfo/synth-diy" moz-do-not-send="true" class="moz-txt-link-freetext">https://synth-diy.org/mailman/listinfo/synth-diy</a><br>> Selling or trading? Use<span class="Apple-converted-space"> </span><a class="moz-txt-link-abbreviated" href="mailto:marketplace@synth-diy.org">marketplace@synth-diy.org</a><br><br><br>________________________________________________________<br>This is the Synth-diy mailing list<br>Submit email to:<span class="Apple-converted-space"> </span><a class="moz-txt-link-abbreviated" href="mailto:Synth-diy@synth-diy.org">Synth-diy@synth-diy.org</a><br>View archive at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/pipermail/synth-diy/" moz-do-not-send="true" class="moz-txt-link-freetext">https://synth-diy.org/pipermail/synth-diy/</a><br>Check your settings at:<span class="Apple-converted-space"> </span><a href="https://synth-diy.org/mailman/listinfo/synth-diy" moz-do-not-send="true" class="moz-txt-link-freetext">https://synth-diy.org/mailman/listinfo/synth-diy</a><br>Selling or trading? Use<span class="Apple-converted-space"> </span><a class="moz-txt-link-abbreviated" href="mailto:marketplace@synth-diy.org">marketplace@synth-diy.org</a><br></div></span></font></div><br><fieldset class="moz-mime-attachment-header"></fieldset><pre wrap="" class="moz-quote-pre">________________________________________________________
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</pre></blockquote><pre class="moz-signature" cols="72" style="caret-color: rgb(0, 0, 0); font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;">--
I am slowly moving to <a class="moz-txt-link-abbreviated" href="mailto:hugh@blemings.id.au">hugh@blemings.id.au</a> as my main email address.
If you're using <a class="moz-txt-link-abbreviated" href="mailto:hugh@blemings.org">hugh@blemings.org</a> please update your address book accordingly.
Thank you :)</pre><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;">________________________________________________________</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;">This is the Synth-diy mailing list</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;">Submit email to:<span class="Apple-converted-space"> </span></span><a href="mailto:Synth-diy@synth-diy.org" style="font-family: Helvetica; font-size: 12px; 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font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;">https://synth-diy.org/mailman/listinfo/synth-diy</a><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;">Selling or trading? Use<span class="Apple-converted-space"> </span></span><a href="mailto:marketplace@synth-diy.org" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;">marketplace@synth-diy.org</a></div></blockquote></div><br></body></html>