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<div class="moz-cite-prefix">Hello<br>
<br>
<br>
<div class="moz-cite-prefix">Am 04.01.25 um 19:34 schrieb Oren
Leavitt via Synth-diy:<br>
</div>
<blockquote type="cite"
cite="mid:868bd020-2c2e-4de6-8059-ea88cdaa490b@proton.me"> I
wonder if that buffer op amp is seeing a capacitive load and is
oscillating at high freq?
Try a 100 ohm resistor between it and the VCO1. If that cures
the issue, place the 100 ohm R "in-loop" with the buffer - there
are example of this for capacitive decoupling in most op amp
datasheets.
<br>
</blockquote>
I did not check the line with an scope, but a 100 ohm resistor
helped. Thank you.<br>
<br>
<br>
<br>
Am 04.01.25 um 18:23 schrieb René Schmitz:<br>
</div>
<blockquote type="cite"
cite="mid:7ed488e7-a423-457c-a507-00d1784db11d@schmitzbits.de">This
opamp is likely similar to a 324 / 358 or 741. Sometimes a high
impedance causes problems. Maybe the 072 is too modern. 🙂
<br>
Also try an LM358.
</blockquote>
I will try LM358 too. I had to make an order at tme.eu anyway...<br>
<br>
<br>
Thanks to everybody!<br>
<br>
Florian<br>
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