anyone know's why AN383 say's that Si4703 is not subject for whip antenna.

I have build a intercom to my Mc with Si4703, now I see that whip antenna is not supported?


Regards Michael

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  • Hi,

    It has come to my knowledge that Si4703 can function with a whip antenna. Thank you for that.

    As it is now it is mounted on a motorcycle communicating with a PIC24FV204, it works allmost satisfying.

    I would like the reception to be a little closer to a car radio reception. I will mount a 1/4 wave antenne at the rear instead of the pseudo 1/4 wave at front, I will be back with the result.



  • Elmek,


    Any conclusions for your whip antenna?

  • I have not had time for it, but the bike will be on stand from 1 december to 1 marts, so at spring 2018 I will test if a real 1/4 wave antenna will do the trick. 

    As it is now, when I drive through the country ex. 200km I sometimes only have 1 station I can hear. Daily driving close to city'es is allmost ok.

    I suspect that there is something in the Si4703 that is not meant for car/bike application? but I hope for the best. 


    Regards Michael

  • I'm using the SparkFun breakout board that uses the headphone wire as the antenna, and I've been very impressed with the reception.  I can actually tune more stations than any other radio I own, likely due to the default seek threshold value.


    Anyway, the reason I was asking was because eventually I would like to move all my my development into my truck/car, and will need to utilize connection to an amplifier and a different antenna.

  • Okay, I am using a similar breakoutboard from ebay, I have not tried with headphone antenne.

    I used Silicon labs AN383 as guideline for alter the antenne input. 

    I have tried compensating with coil's at the antenne, until maximum reading at RSSI but I only got 3db out of it, it wasnt enough.

    My treshold for accepted stations is set low. I accept some noise at a station and I only use mono.

    I have considered a antenne amplifier because if I drive with short distance to a transmitter I get at most 61dbuV and the Si4703 chip can measure rssi up to 75dbuV. (Si4702-03-C19-1.pdf ), so perhaps you are right with a amplifier. 

    I think the breakout board is great for your application, except from my experience with the signal strenght.

    I would like to hear what you can achieve with the breakoutboard


  • Elmek,


    Eventually, I'll make my work public if I finish up.  I'm interfacing the Si4703 with a Raspberry Pi via i2c (2-wire).  I've written a class based device driver in Python to interface the Si4703...and I've had a lot of fun writing it.  I'm not a formally trained programmer, just learning as I go.


    Anyway, the best rssi value I've seen is in the low 60's...with most in the low to mid 40's.  Those at the lower end, still seem to sound pretty good though.