15 Feb 2011

4m transverter schematic

70MHz (4m) 1W pep transverter
The schematic of my QRP transverter for 4m (70MHz) is attached here and is also available on my website. Can't promise there are no errors but this is close to the real circuit as implemented. If anyone fancies having a go at this please remember this is a starting point and some optimisation of components and tuned circuit values may be needed with spreads in parts etc. As far as I am concerned this project is now complete and I have taken it as far as I want to for now.
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3 comments:

  1. AnonymousWed Feb 16, 06:46:00 am GMT

    Thanks for the nice drawing Roger. It's a good source of ideas.
    Congrats with your first 4m qso with this small transverter.
    73
    Ron

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  2. Ricardo - CT2GQVWed Feb 16, 08:13:00 pm GMT

    Hello,
    Nice design. Thank you for sharing.
    Have you tried putting the LO oscillator directly to the NE602 (removing T2), or not enough signal to drive T1?
    Was T7 really necessary or not enough bias power from the FT-817?

    73 de Ricardo - CT2GQV

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  3. AnonymousFri Feb 18, 02:34:00 pm GMT

    Hello Roger,
    Our radioclub has the intention to use your design as a start for a 4m transverter club project:

    http://www.pi4raz.nl/index.php?option=com_content&task=view&id=2227&Itemid=43

    Will keep you informed about the progress,
    73 Ron
    PA2RF

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