VCO

https://www.ericasynths.lv/media/VCO_MANUAL_v2.pdf
https://www.falstad.com/circuit/

$ 1 0.000005 58.6985430941709 62 5 50 5e-11
R 1360 592 1280 592 0 0 40 0.5 -0.002800000000000004 0 0.5
w 1360 592 1408 592 1
32 \0 0 1e-13 0 0 1.5 0 0 2 1 1 0 0 1
t 1408 592 1456 592 0 1 -2.0588638868895157 0.4972 100 \0
g 1456 640 1456 688 0 0
w 1456 608 1456 640 1
c 1536 624 1536 576 0 2.2e-7 -2.5560638868895156 7
g 1536 624 1536 688 0 0
183 1648 576 1792 576 0 0.5 1.66 3.33 5 0
d 1792 496 1648 496 2 default
r 1792 576 1792 496 0 100
w 1648 496 1648 576 0
w 1536 576 1648 576 0
w 1536 576 1456 576 0
w 1536 576 1536 432 0
w 1536 432 1904 432 0
a 1904 416 2016 416 8 15 -15 1000000 2.5560383265062505 2.5560638868895156 100000
w 2016 416 2016 336 0
w 2016 336 1904 336 0
w 1904 336 1904 400 0
w 2016 416 2096 416 0
c 2096 416 2176 416 0 0.000001 2.491925772685179 0.001
r 2176 416 2176 512 0 100000
g 2176 512 2176 544 0 0
w 2176 416 2272 416 0
a 2272 432 2416 432 9 15 -15 1000000 0.43500000000000005 0.06411255382107124 100000
R 1296 800 1248 800 0 0 40 0 0.43500000000000005 0 0.5
w 2416 432 2480 432 0
w 1296 800 2272 784 0
w 2272 448 2272 784 0
x 1214 773 1272 776 4 24 PWM
x 1221 570 1335 573 4 24 Frequence
x 2201 334 2395 337 4 24 sortie\sdent\sde\sscie
x 2425 407 2549 410 4 24 sortie\sPWM
w 2272 416 2272 368 0
o 14 64 0 4103 10 0.0001953125 0 2 14 3
o 23 64 0 4103 1.25 0.00009765625 0 2 23 3
o 26 64 0 4103 20 0.00009765625 0 2 26 3
38 0 F1 2 -0.035 0.035 -1 VCO
38 25 F1 2 -0.75 0.75 -1 PWM