Sources for these are given below,
Ashar Farhan's signal generator (DXZONE) This is a single output VFO.
His copyright allows free reproduction rights if you keep all his (interesting) text as well, in the interests of space I just give a link here and some notes. He provided two ranges of 3-10MHz and 10-30MHz.with two Hartly oscillators are used, one for each range. Simple JFET fed from a tapped coil and variable cap, he uses a pull down 220k and 1N4148 on the gate. Coils are 60t(30t) of 28swg would on thick McDonald's(Subway!) straws tapped at 15(8) and 365pF, uses a 2.2pF(4.4pF) coupling cap between the tank and the gate. VFO's feed a JFET, a 6dB attenuator and then 2x BJT(one to frequency counter one to output) The RF output has a further 6dB pad to give a 50 Ohm output. drift 10Hz@3.5MHz, few hundred a minute on 14MHz. He unplugs the digital freq meter when making sensitive readings.
ZL2PD HF RF
Signal Generator A simple 450k - 60MHz in 3 switched rangesNice simple
circuit - Franklin, tank straight into a Jfet, emitter coupled to another which
has a grounded gate, its drain feeds back via a 5p6 cap. o/p across (common)
source 330 resistor thru a 120p to a cascode bjt. minimal component count. His
tank uses a 10-160pF air spaced and three coils.
ZL2PD SingleSpanOsc 400kHz to 30MHzoutput is 300-400mV into 50 Ohm 
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