HF receiver front end IC

[smoothcriminal]

I am designing a HF receiver for WWV signal (10 MHz)... can its front end.. i.e Selectivity and amplification be done through an IC ??? if yes kindly give me he name of that IC ??

 

[wbain]

You would be better off using FETs. There are many existing receivers capable of receiving WWV. Good luck.

Kenwood, Yaesu, ICOM for instance, make good receivers/transceivers.

 

[Mooly]

Moved to everything else 🙂

DIY RF design is something rarely seen these days.

 

[DF96]

A chip can do amplification, but for selectivity you need filters: LC, ceramic or crystal are the usual technologies used at HF. Alternatively, there is the software-defined-radio approach, in which most of the filtering is done digitally.

For receiving a single fixed frequency the simplest techniques might be either TRF with reaction, or direct conversion (also known as zero IF). Google will help you.

 

[smoothcriminal]

Thanx guys.. i googled and found out this receiver front end:
http://www.qrp.pops.net/images/before 2008/wwv_10MHz_Files/WW1.GIF

I am thinking of building that one out...

 

[DF96]

Cascading two dual-gate MOSFETs will give you a lot of gain, so stability will be an issue. Include a lot of screening to ensure the input can't 'see' the output, otherwise you will just have a 10MHz oscillator.

 

[smoothcriminal]

And How exactly does Screening can be ensured in this circuit.???
and I guess the purpose of the Variable Resister in the circuit would be to provide that much gain that doesn't overdrive the next stage.

 

[Osvaldo de Banfield]

I had used a TDA1220B for a ham radio receiver and works properly, with a MOSFET RF stage. You can get audio directly from the chip, locas osc. included, and FM DC switching. For SSB, you must add mix oscillator externally.