Yeah, I sort of figured when Smath told me sqrt(LC)=3D time.=20 For general tank circuits I agree, but tank circuits used as antennas may a= ct differently, especially inside the evanescent field area. -----Original Message----- From: piclist-bounces@mit.edu On Behalf Of Dave T= weed Sent: Monday, October 22, 2018 2:16 PM To: piclist@mit.edu Subject: Re: [EE] What's up with this one wierd trick? David Van Horn wrote: > Now I'm told that to find the "best" values, I should take these=20 > values and calculate Sqrt (LC) and use that value for the inductor and ca= pacitor. >=20 > When I pull the Sqrt of (L*C) the result is in time. 159nS in this case. > I start to feel like we're doing something sketchy here, but I plug in=20 > 159uH and 159pF and I get another resonant pair at 1MHz with ZL or Zc =3D= 1k. >=20 > Running a couple of different examples, it seems I always end up with=20 > 1k Impedances. >=20 > Is this wierd trick legit? No. The "wierd trick" is simply based on the fact that you chose an L value tha= t is 1,000,000 times larger than the C value. The square root of that ratio= is 1000. If you had instead *followed instructions* and used 159 nH and 159 nF, you = would have gotten impedances of 1 ohm for both. And if you keep going, 159 pH and 159 uF gives you 0.001 ohms. There is no "best" set of values, except as determined by other constraints= such as manufacturability. -- Dave Tweed -- http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/chang= e your membership options at http://mailman.mit.edu/mailman/listinfo/piclis= t --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .