Proposed DSB TXRX for 80m

So i was reading about a design for a RXTX for DSB on 80m, and I had some thoughts about it, so I designed this circuit - it has not been made, but could inspire someone to have a go:



There is no RX/TX switching so this has to be done externally, in the PA - the ones I proposed earlier might be modified to do this.

I have researched all the components, the torrid and the MOSFETs and chosen the best ones. The coils are always a problem, finding the right ferrets and variable coils, but I think the Farnell 18009 and 18008 will be OK for the receiver and transmitter, and the Toko A7BRS-T1040Z (Digikey TK2417-ND or TK5117-ND) should be OK for the VFO. The capacitance values may have to be tweaked to get the right frequency coverage.

The MOSFETs BFR31 and 30 seem to be great devices for low level RF use as they are easily biased, actually nnot needing any bias but conducting a few milliamps with VGS = 0.

The audio side has not been thought out and may have the wrong gain needed, again play with the feedback around the op-amps to get this right. The transmit op-amp gain will affect the modulation and needs to be carefully set so not to over-modulate the output.