Not gonna lie here, I am poor as shit as of lately and the only FM TX I have is a modified Ramsey FM10c using a varicap combo for tuning along with rf amps and filters to get to 10 watts. It's actually very stable until the room temp changes! In winter time our furnace kicks in and the room temp can go from 68 to 72 degrees and then cools back down until it kicks in again. This ticks me off something terrible because during other times of the year the freq. stays mostly locked besides a slight retune every 5 or more hours since summer/spring/fall is mostly regulated temps. But in winter it's crazy, like as soon as the heat kicks in my freq. goes from 96.90 to 96.95 then cools and goes to 96.85. It's a complete bitch. Yes I should get a PLL or solid rig but this is what I have for now until money falls from the sky. So any ideas on getting a VFO to not drift with temp changes?
Problem fixed. Replaced all caps with NPO types and used multiple capacitors in place of where single caps were to make the VFO stability better. Replaced the stupid 3 regulator diodes with a good zener type. Metal enclosure+fan, good ground and a few other mods and the thing is as stable as a rock now. After 5 min warmup just a slight dial tune and the VFO stays put for hours on channel. Ugh talk about a total rehaul of the kits design lol. Closed thead since it's fixed.
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