can someone tell me where to find some circuit schematics for a megaphone that uses an eletret condenser mic and one of the following amplifier ic's: lm324 quad op amp with 14 pins, or 742 op amp mini dip ic with 8 pins. and also using no transistors or germanium diodes
Op-amps are signal devices, not power devices. Using them for a megaphone, the output would be significantly quieter than your voice at the input! Megaphones frequently use class-C amplification. It is dreadfully distorted, but very efficient and just about clear enough for the application. Search for megaphone/bullhorn schematics. You'll need to source a horn speaker for it too, it might be cheaper to buy one?
one of the following amplifier ic's: lm324 quad op amp with 14 pins, or 742 op amp mini dip ic with 8 pins. and also using no transistors or germanium diodes
The LM324 has terrible crossover "distraction". Its output transistors operate in class-B to reduce supply current (it is low power) instead of class-AB.
the reason i want to make a variable cap is to be able to make a simple ham radio transciever for morse code but every circuit i have seen so far requires components that i cannot get my hands on. the two main things that i keep seing are germainum diode and variable cap neither of which i can get. so if one of u could help me find a circuit for a ham radio that doesnt use a germanium diode and doesnt need that many transistors ( i forgot to mention the radio shack i live near has a very limited variety of them too) or diodes and if it does require some diodes and transistors plz supply me with a list of possible substitutes btw if it helps i now have a lm 386 available to me.
the reason i want to make a variable cap is to be able to make a simple ham radio transciever for morse code but every circuit i have seen so far requires components that i cannot get my hands on. the two main things that i keep seing are germainum diode and variable cap neither of which i can get.
Can you post a link or .bmp of the receiver's schematic? I'd like to see this curcuit you are working on. There are lots of ham radio basic receiver schematics on the internet for you to choose from.
I don't think anybody ever made a ham radio transceiver from RadioShack parts before.
Why not buy real electronic parts from a real electronic parts distributor? They have hundreds of germanium diodes and thousands of variable capacitors in stock, all with detailed spec's.
yeah that's pretty basic! Why not try building from a kit like the ones offered by MFJ? They make some decent stuff and it actually has some worthwhile specs. as well.