This circuit filters low frequency noise from the turntable motor. We found it in a 1989 documentation. The font doesn't have to be symmetrical, but it should have excellent filtering.
The circuit shown in the figure is suggested by Texas Instruments and allows data transmission on TTL devices...
We find this vibrato configuration with transistors in a 1987 documentation. The components are still...
This circuit, from a documentation from the 1970s, produces two sinusoidal signals given by C2 and...