I came across this link: https://www.avx.com/docs/techinfo/mlc-tant.pdf ...
which points out that Y5V dielectric capacitors chance their effective
capacitance across about a 5:1 range depending on the DC basis. Has anyone
used this "feature" to obtain tuning in a radio? Similar to using a varactor
diode's capacitance for the same effect? I'm thinking that it might not work
as well as a varactor diode (especially given Y5V's very significant
temperature dependence), but it still seems like it could be a novel idea for
a low parts count receiver that didn't need particularly stable tuning.

---Joel Kolstad

On Sat, 22 Oct 2005 21:15:35 -0700 "Joel Kolstad"
wrote:

I came across this link: https://www.avx.com/docs/techinfo/mlc-tant.pdf ...
which points out that Y5V dielectric capacitors chance their effective
capacitance across about a 5:1 range depending on the DC basis. Has anyone
used this "feature" to obtain tuning in a radio? Similar to using a varactor
diode's capacitance for the same effect? I'm thinking that it might not work
as well as a varactor diode (especially given Y5V's very significant
temperature dependence), but it still seems like it could be a novel idea for
a low parts count receiver that didn't need particularly stable tuning.

The 5:1 range is more than I remember. All class 2 ceramics will do
this to some extent, but the nonlinear tempco is the drawback.

Varactor diodes have a much smaller C range, but that can be dealt
with.

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Jim Adney
Madison, WI 53711 USA
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