Trying to build a wireless mike for a guitar, not having much luck:
> 1. I have substituted MPS2222A tranistor for 2N2222. Is this ok for
> this type of application? I was just guessing that the 2222 means they
> are similar ;-)
> 2. How can you measure a coil's inductance? If you make the coil
> yourself, can you be sure its "correct" somehow?
> 3. For testing, I have a 555 timer creating an a sound, that when
> hooked up to a speaker sounds like a high pitched tone. at close range,
> the tone is heard on FM radio, even without being hooked up to the
> transmitter circuitry. Why is this? If the tone is audible, how are
> radio waves in the FM band being produced? Is it ok to substitute such
> a circuit for an electret mike, which will eventually be a feed from the
> guitar or effects board?
> 4. How can I tell if I'm even getting RF waves out of my circuit? Can
> an oscilliscope hooked up to the antenna tell me if i'm atleast getting
> oscillation?
>
> This is my first basic circuit that doesn't have led's or sound or
> something to allow me troubleshoot and "see" what's happening. Any tips
> on how to troubleshoot RF circuits like these?
> Thanks
Using hearsay as a source of specific manufacture specifications information is full of misinformation. Spec. sheets are just a click away.