| Version 4 | |
| Low pass filter | |
| SHEET 1 880 680 | |
| WIRE 160 64 64 64 | |
| WIRE 288 64 240 64 | |
| WIRE 64 112 64 64 | |
| WIRE 288 112 288 64 | |
| WIRE 64 224 64 192 | |
| WIRE 176 224 64 224 | |
| WIRE 288 224 288 176 | |
| WIRE 288 224 176 224 | |
| WIRE 176 240 176 224 | |
| FLAG 176 240 0 | |
| SYMBOL res 256 48 R90 | |
| WINDOW 0 0 56 VBottom 2 | |
| WINDOW 3 32 56 VTop 2 | |
| SYMATTR InstName R1 | |
| SYMATTR Value 1K | |
| SYMBOL cap 272 112 R0 | |
| SYMATTR InstName C1 | |
| SYMATTR Value 1� | |
| SYMBOL voltage 64 96 R0 | |
| WINDOW 123 24 124 Left 2 | |
| WINDOW 39 0 0 Left 0 | |
| SYMATTR InstName V1 | |
| SYMATTR Value "" | |
| SYMATTR Value2 AC 2 | |
| TEXT -8 256 Left 2 !.ac dec 20 1 1MEG | |