zachtheterrible
Active Member
I've built this transmitter here once and it worked pretty good, even though I think that I was hearing harmonics over the radio. Well, I built this same transmitter again, but w/ some small changes:
Where C4 is, I put another capacitor in series w/ it. Actually, I took an ic socket and cut it so that I could solder two sockets into the circuit and then be able to put different capacitors in, therefore being able to have a huge range of frequencies.
I also made L1 smaller. It is supposed to be 1/4 an inch w/ 6 to 8 turns, but I made it 1/8 an inch w/ the same amount of turns.
The circuit does not work. I made a very simple RF field detector that works great, and it picks up nothing. Last time that i built this circuit, it didn't work, and come to find out later, all that was wrong with it was I burnt C3 while soldering. I was very careful with that capacitor this time; I put a heat sink on it.
Anyways, I made a metronome that produces a series of clicks, or whines, depending on the value of capacitor in it. Is this a reliable way to test the higher value capacitors in this circuit?
The two changes that I made to the circuit, they wouldn't make the circuit stop working, would they? Since I made the inductor smaller, this would boost the frequency, but how much? I put in a higher value capacitor for C4 (100 pf), so hopefully that would lower the frequency enough so as not to go above the transistor's highest frequency rating.
Lastly, is there a way to test the transistors without pulling them out of the circuit?
Where C4 is, I put another capacitor in series w/ it. Actually, I took an ic socket and cut it so that I could solder two sockets into the circuit and then be able to put different capacitors in, therefore being able to have a huge range of frequencies.
I also made L1 smaller. It is supposed to be 1/4 an inch w/ 6 to 8 turns, but I made it 1/8 an inch w/ the same amount of turns.
The circuit does not work. I made a very simple RF field detector that works great, and it picks up nothing. Last time that i built this circuit, it didn't work, and come to find out later, all that was wrong with it was I burnt C3 while soldering. I was very careful with that capacitor this time; I put a heat sink on it.
Anyways, I made a metronome that produces a series of clicks, or whines, depending on the value of capacitor in it. Is this a reliable way to test the higher value capacitors in this circuit?
The two changes that I made to the circuit, they wouldn't make the circuit stop working, would they? Since I made the inductor smaller, this would boost the frequency, but how much? I put in a higher value capacitor for C4 (100 pf), so hopefully that would lower the frequency enough so as not to go above the transistor's highest frequency rating.
Lastly, is there a way to test the transistors without pulling them out of the circuit?