Hey everyone! I have a friend that has requested an fm transmitter from me.. I cant build a design myself, i can only replicate it atm.. the forum videos/worksheets have brought me a long way though!
Ive made a couple of these, as my first attempts as pcb using thru-hole components. Muriatic acid/ hydrogen peroxide to etch copper board, and MS paint to design traces:
It has worked well for me, but always needs a bit of tinkering with tuning... I would like to omit the variable capacitor, and install a sp4t rotary switch, with predetermined capacitors to make it used friendly.(ex: 5pf = 87.5fm etc) obviously id have to adjust the coil length to get my starting parameter, and go from there.
question is, is this a good schematic to work on?
ive also found these:
Ill add i have 20 of the maxim2606 IC already..
then theres this:
And if your not bored yet, i have built this a while back.. but didnt work properly and gave up figuring it was first project screw up.. ****Question is here, if i replicate this schematic(properly), can i simply replace the mic with a pair of rca jacks/ or 3.5mm? and combine then left & right signal as shown in 2nd and 3rd posted schematic?****
Also, will the 3 transistor schematic posted be more "stable"? as i said, i need this to be user friendly.. So much as you'd let you mum use it with out worry lol!
OR, is there a better alternative that i haven't found yet that one might recommend? (i wont buy one- price sux, and so does range!)
Stability is the main worry here. And as she travels from time to time, id like to have preset caps to determine freq output..From what ive learned var caps/ pots have a very short sweeping lifespan, and shouldnt be used for frequent tuning.
Completely open to suggestions, and any advice one might give.
Hoping to get started ordering parts! Thanks in advance!!
Ive made a couple of these, as my first attempts as pcb using thru-hole components. Muriatic acid/ hydrogen peroxide to etch copper board, and MS paint to design traces:
It has worked well for me, but always needs a bit of tinkering with tuning... I would like to omit the variable capacitor, and install a sp4t rotary switch, with predetermined capacitors to make it used friendly.(ex: 5pf = 87.5fm etc) obviously id have to adjust the coil length to get my starting parameter, and go from there.
question is, is this a good schematic to work on?
ive also found these:
Ill add i have 20 of the maxim2606 IC already..
then theres this:
And if your not bored yet, i have built this a while back.. but didnt work properly and gave up figuring it was first project screw up.. ****Question is here, if i replicate this schematic(properly), can i simply replace the mic with a pair of rca jacks/ or 3.5mm? and combine then left & right signal as shown in 2nd and 3rd posted schematic?****
Also, will the 3 transistor schematic posted be more "stable"? as i said, i need this to be user friendly.. So much as you'd let you mum use it with out worry lol!
OR, is there a better alternative that i haven't found yet that one might recommend? (i wont buy one- price sux, and so does range!)
Stability is the main worry here. And as she travels from time to time, id like to have preset caps to determine freq output..From what ive learned var caps/ pots have a very short sweeping lifespan, and shouldnt be used for frequent tuning.
Completely open to suggestions, and any advice one might give.
Hoping to get started ordering parts! Thanks in advance!!