From 6a75727dc6b8040bb087a055a1735cd1180a300f Mon Sep 17 00:00:00 2001 From: Daniel H Date: Mon, 1 May 2023 21:25:15 +0200 Subject: [PATCH] fix circuit diagram --- README.md | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/README.md b/README.md index 0b8434e..f3bc93b 100644 --- a/README.md +++ b/README.md @@ -39,21 +39,18 @@ AM signal on pin 15. ## Circuit Diagram and explanation -![Image of circuit diagram](https://media.discordapp.net/attachments/1077080199847489626/1102203487363792956/SmartSelect_20230430_140248_Flexcil.jpg) +![Image of circuit diagram](https://user-images.githubusercontent.com/48156391/235515258-df6d10fa-90f5-4997-813d-1cf969dbf8a0.png) The part which prepares the audio for the pico is not strictly needed, but if you use line inputs, you reeeally should have it. It has the following jobs: -- R2 and R3 try to pull AI- a between the two voltages to be able to record the whole signal in case it is not a grounded one (not needed, - it can also just be connected to ground. this is basically just extra fanciness with nonzero but very small benefit.) -- R1 makes sure there isn't too much strain put on the input - D1 and D2 clamp the signal to acceptable voltages - **An extra resistor of about 50-100 ohms may be added from the AI+ point to the AI- point to load the signal.** This is optional, but *can* clean up a little bit of noise if you have long cables. **ERRATA :warning:**
If you aren't an asshole, ***PLEASE*** add the low pass filter as mentioned in the Disclaimer: -- Add a 100ohm resistor between pico and antenna -- Wire a 2nF (2000pF) capacitor between the new start of the antenna and ground +- Add the 100ohm resistor (R3 in new schematic) between pico and antenna +- Wire a 2nF (2000pF) capacitor (C1 in new schematic) between the new start of the antenna and ground ## How to use it