Step 7: Transistors, LED, and Diodes

Next we want to place the Transistors and Diodes.

Make sure you orient the transistors correctly. Check the reference image and have the flat side of the transistors facing to the left of the board. This lines up the transistors so the Emitter is on top, the Base is in the middle and the Collector is on the bottom. Q4 is the C1674 transistor and the leads will need to be bent out to fit the board. The BC547 transistors go to Q1 through Q4. 

With the LED and Diodes its important to pay attention to which lead is the Anode and which is the Cathode. On the LED one lead is longer then the other indicating the Anode. So your short lead is the cathode and should be on the bottom side of the board. The Diode's cathode is indicated with a white line around one end of it. That line should be facing the top of the board.

Like before bend the lead out a bit in the direction they need to go. Flip the board over and solder the leads into place. Then rout the leads and trim as needed.
What software was used for the pcb layout?
<p>See step 3. </p>
<p>Can this be used for tire pressure Montoring system? I believe they operate at 315 MHz? I assume most are binary; either send a signal or no signal. </p>
<p>by any chance would it work with a galvanometer</p>
<p>Hey there, made the project. Was a fun one to do. But in my variation it doesn't work well. If I solder the L2 the LED will not be on and it won't work. If I don't solder L2 then it will continuously whistle. I double checked for everything. The only major modification is Q4 as you can see in the image. Maybe you could help me out. </p>
<p>Very clean looking circuit. Great work!</p>
<p>Could the bug and this receiver function as a remote control circuit? Seems like you could make a DIY remote control device this way.</p>
<p>No not really. Quite a bit more copmplicatd than this. But there are plenty of hobby RF transmitter and reciver kits out there for that sort of thing. </p>
Did you actually put antenna inside metal box? I don't think you will get anything with that cage around antenna
The antenna is only stored in the box. You pull it out when doing a sweep.
Good. God. <br> <br>No ground plane??
Not for the Pegboard version. Leaving the ground fill out of the Pegboard layout and reference images makes it easier for beginners to keep track of what component goes where. If you download the PCB files for etching your own board the ground plane is there.
Try using a RF probe instead

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