What would you lot say the best first RF project is assuming you already have basic electronics knowledge?

Better sound quality and more stable than one transistor bugs. Very hard to make it not working... It was my first serious RF project

What transistors did you use, I have BF199's here do you reckon they will work?

I used BF199 (BF240, BF494 will suit too). It works with many low power RF transistors. There's some modifications thats makes this circuit working better. This is Seiler oscillator. It's very universal - you can widely experiment with components values. Coil is 5 turns on 5mm dia.

Probably just make an oscillator on a selected frequency would be a good start. That’s what I did.

Did you build this on copper clad with islands?

Bton-FM wrote: ↑Thu Feb 27, 2020 9:01 pm Did you build this on copper clad with islands?

exactly

XXL wrote: ↑Thu Feb 27, 2020 9:00 pm Probably just make an oscillator on a selected frequency would be a good start. That’s what I did.

On my schematic there's just a simple oscillator . Only two things more : modulation circuit on BB105 varicap - to allow frequency changes by audio signal, and buffer to improve frequency stability - antenna connection don't change the freq.

also have you added a pll to this before?

Yes - based on SAA1057. You must throw out 100k trimm and connect there PLL voltage output. The reference signal You can take form emitter of first transistor.

did you use the pira one?

Not completely - Hardware is from pira (with small changes), and soft (with some changes too) form : http://www.easy-soft.net.pl/artykuly/ba ... ci-saa1057

Software is your choice - it easy to write it yourself using basic or c.

I know Fcuk all about coding haha

well, there are some old programs that allow to control SAA1057 and TSA5511 from PC. But if I remember they operate on archaic LPT port

would you say this could be worked into something fit for broadcast or not?

This little two stages circuit ? I think it has too low power But if you marry it with PLL and amplifier stage - of course
But, even with small power with high mounted antenna there's possible to cover big area - I know someone who had 20km range with only 20mW

Yeah I meant with an amplifier

how much power does this output?

A few mW (i guess <10mW) - output power can be adjusted by change of oscillator emitter resistor. If You want to add next stages, better idea is get rid off the buffer stage and put there high gain amplifier on dual gate mosfet or BFR91/96.

what do you use for the 28v supply.Does it have to be that high?

1608cc wrote: ↑Thu Feb 27, 2020 9:38 pm I know someone who had 20km range with only 20mW