<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div dir="ltr"></div><div dir="ltr">Yes, of course. This is rotine, to evaluate temperature stability of circuits being developed. Early simple example: <a href="http://ijfritz.byethost4.com/sy_cir2.htm">http://ijfritz.byethost4.com/sy_cir2.htm</a></div><div dir="ltr"><br></div><div dir="ltr">Ian</div><div dir="ltr"><br></div><div dir="ltr"><br><blockquote type="cite">On Sep 10, 2023, at 10:45 PM, brianw <brianw@audiobanshee.com> wrote:<br><br></blockquote></div><blockquote type="cite"><div dir="ltr"><span>Does anyone here have access to a thermal chamber where the temperature drift of a given circuit can actually be assessed?</span><br><span></span><br><span>My assumption is that things will probably work fine under "normal" conditions, but as soon as a musician brings gear in from a cold climate to a warm venue, or even starting from comfortable climes and then temperatures inside climb to sweaty, humid heat, there might be problems that didn't show up in the home studio.</span><br><span></span><br><span>Brian</span><br><span></span><br><span>On Sep 10, 2023, at 6:22 PM, crys <crystals@sonic.net> wrote:</span><br><blockquote type="cite"><span>I acquired a bunch of THAT 320 and 300 and used them for quite a few ircuits. Sometimes it was likely overkill, like when i built a ladder filter with them. I found them to be easy to work with and quite stable. They do cost but i think i either got a deal or bought a quantity. It was a decade ago. I did score about 20 LM394 cans but it was just as i packed up my lab to storage, I'm interested in what's what now. I have made a tester and matched them myself, as already menioned quite easy these days. I started matching resistors, too, which was quite easy. I also built plenty of modules with just transistors from a new lot that sounded just fine.</span><br></blockquote><blockquote type="cite"><span></span><br></blockquote><blockquote type="cite"><span>On 9/9/2023 6:21 PM, Paul Glass-Steel via Synth-diy wrote:</span><br></blockquote><blockquote type="cite"><blockquote type="cite"><span>I’ve had good results with those too. </span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span></span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span>On Sat, Sep 9, 2023 at 4:20 AM Mike Bryant <mbryant@futurehorizons.com> wrote:</span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span>Nxperia also do dual transistors without the base resistors e.g. BC856S. They are on the same die so will be well matched.</span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span></span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span>From: Synth-diy <synth-diy-bounces@synth-diy.org> on behalf of Scott Bernardi via Synth-diy <synth-diy@synth-diy.org></span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span>Sent: 09 September 2023 00:33</span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span>To: SDIY List <synth-diy@synth-diy.org></span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span>Subject: [sdiy] What do people use for matched transistors these days?</span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span></span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span>Right now I'm looking at matched pnp's, suitable for a VCO. Something like the THAT-320 quad pnp would be ideal, but they are kind of pricey. The quad is nice because you have an extra matched transistor you can use for high frequency tracking adjustment.</span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span></span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span>I ordered some BCM856's to see how they will pan out. I think the VBE match will be good enough, I'm wondering about the base resistance that causes deviation from ideal log conformance.</span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span></span><br></blockquote></blockquote><blockquote type="cite"><blockquote type="cite"><span>For npn's, THAT-300 or MAT14 are the best, also pricey.</span><br></blockquote></blockquote><span></span><br><span></span><br><span>_______________________________________________</span><br><span>Synth-diy mailing list</span><br><span>Synth-diy@synth-diy.org</span><br><span>http://synth-diy.org/mailman/listinfo/synth-diy</span><br><span>Selling or trading? Use marketplace@synth-diy.org</span><br></div></blockquote></body></html>