Designing a 144-146 VHF TRX for HAMS

  • Sunday, November 7, 2010
  • KPS
  • I have seen some circuits in the internet and got an idea to make a efficient VHF TRX for hams, so working on that, it may take a more time as i am having little knowledge and have to improve a lot in the RF field where i am feared of coil winding.

    Completed RX Stage of HMY2K8

  • Thursday, November 4, 2010
  • KPS
  • Successfully complted the RX stage of HMY2K8 with help OM Dr.Rajasekhar, and still i am aligning for the best results and to recieve DX stations. Hope i will get a very good quality.

    The RX Stage is quite simple first the audio amplifier is to be completed and to be checked whether it is working or not a simple test like giving any auido input to the 6th pin of LM380 your speaker should shout with the amplified output, keeping this amplifier working next stage is IC2, complete all the circuitaey which needs to run the IC and then just put your antenna pin to the 1st pin of IC2(product detector) soon you should recieve some wideband of stations, with this test you are ready with your product detector next step is with the mixer IC1...will update soon

    Interface Unit for HAM Radio Equipment and Computer

  • KPS
  • Firstly i heart fully thank Rahul Srivastava, VU3WJM, who built this circuit, i just completed this project and i want to give some help to the HAMS who want to build this.


    This is a circuit which can be built very easily with the easily available components in VU land and nothing is critical in this design. 
     
    This unit supports so many modes like PSK31, MFSK16, MT16, Hellschriber, SSTV, RTTY,AMTOR, PACTOR, PACKET, CW and over the net Echolink and Echostation.


    Schematic:











    Printing the PCB:
     

    Component List:
    4N33 Optocoupler-1
    Isolation Transformer(1500/1500 TURNS)-1
    1N4148 DIODES-2
    3K3-1
    10KPF-3
    1K5-2
    33E-2
    100E-1
    500E TRIMMER-1
    1Micro Farad/63volts cap-1
    all the connectors are according to your choice and availability, but the computer needs RS-232 D-socket connector.

    Note: This is just to help the budding hobbyists to make their projects easier and clear with component lists. Contact for more help.
    Copyright 2010 Prasanthz world...