[FrancoItaly]

with my last LRL (I think is the tenth) I had to change the value of two capacitors to make it working. The heart of all the LRL is the high gain part consists of TR2, TR3 and TR4; if the gain is too large this part goes into oscillation and it's very unstable, if instead the gain is too low, the phenomenon is not revealed.I use the type BC183C transistors because I own a lot, but you can use equivalent types (BC109C, BC209C, BC239C and so on) the important thing is that they are NPN silicon with high "beta" (suffix "C"). The RF gain of the amplifier,for a certain range of frequencies, depends on the value of C13 and C14, the lowest value = less amplification and vice versa. I suggest using instead C2, C3 and C4, a single capacitor of 1 pF and measure the output signal (TR5 emitter), if the DC signal is zero should be increased C13 and / or C14 until a stable signal (from 1 to 5V is not critical), if the signal is still zero with C13 = C14 = 100nF increase the value from 1 pF to 1.8pF and repeat the process. In my case I used 1.8pF, and C13 = 33nF, C14 = 10nF. If the signal is unstable even removing the capacitor 1pF must decrease C13 and / or C14.The important thing to point out is that of not increasing too much the value of the capacitor consisting of C2, C3 and C4 in order to obtain a signal at the outputas in this way is masked the low gain of the transistors. As I said the optimum value is 1 ... 2pF or less and it is for this reason that I used three capacitors connected in series, in fact, for example, two capacitors connected in series 1pF give a capacity of 0.5pF
Regards