it works even with a 15 pf cap, but the range of the transmitter is very low (only 10M!).i used a 2n3904 and all the resistors which i used in this project are SMDs , has anyone ever made a 1Km transmitter? It's hard like hell to make a transmitter
I used colin's transmitters
and changed component values as:
Supply volt - 3.7V
10p feedback cap changed to 5p (written only "5" on the cap)
470R emitter resist. Changed to 100R
used only 47K instead of 150K for final stage transistor
.did not add 5-30p cap in final stage and used only a 7turn 0.3mm inductor, 3mm dia
bc547 is used as mic amp and two 2N3904
did not use +1u cap, instead i used a poly cap (a green, sack like cap written 223 on it)
Used 1mm thick copper wire to make L1 6turn coil
Result:
stability is not bad, but the range is only 10M!
The transmitter won't work when i added the last 2n3904 transistor (3rd transistor) so i tested the transistor without 3rd 2n3904,
Hope, collin can understand the mistakes i made,