Hi Geo,
It's correct the capacitor for VCO of CD4046, it depends on type of IC, the phase comparator output (pin 2) is an AC signal, is normally a rectangular wave with variable duty cycle, but at the maximum frequency of the CD4046 can also be triangular, however, I am referring to a measure DC voltage rms value. As for the output X is perhaps better a lower value to make sure that there is no saturation, to achieve what should be decreased P2, if in spite of this you do not have a result decrease C8 and C9 and as a last resort you have to disconnect C8 or C9, in this way will be the parasitic capacitance to bring the signal to the base of TR2. I built 2 copies of this LRL and work well but I realize that it is more simple to build version with the quartz oscillator. The oscillator frequency is not critical and it goes from 3Mhz to 10Mhz may be necessary to change the value of C1 in the oscillator stage. I want to add that to be sure that the amplifier stage does not come in oscillation you have to use a double-sided pcb, the lower side connected to ground and the components soldered on the top side and you have to use another pcb for oscillator stage. I hope that with this aid all of you can build my LRL.
Best Regards
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