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Does a high Q loading coil affect audio?

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I use a Wenzel transmitter, which I understand to be the basic circuit of the SSTran. As I’ve progressively refined my loading coil for an antenna similar to the one on the SSTran website (link below), the audio becomes raucously clipped.

There are probably several ways to clip audio, but I’d like to know if a high Q coil can restrict bandwidth so much that it affects audio.

Alternatively, could the high voltage swings be so much in a high Q coil that the output transistors are saturated or where reverse breakdown occurs?

Or could there be some feedback that affects the modulation transistor?

Thanks for any insight here.

Antenna link: http://www.sstran.com/pages/sstran_amt3000mods.html

Macrohenry

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  1. Q vs. Audio
    The SSTRAN circuit has a biasing scheme which differs from the Wenzel circuit so the performance of the two may not be equivalent.

    Yes, in theory, the antenna system Q could result in loss of some sideband information and if this happens the audio will sound muffled (as if you had cotton in your ears) rather than clipped. I don’t know if it is possible to obtain a Q high enough in practice with the SSTRAN recommended antenna to cause this. This thread has some information about Q and if you search the topic here you will find more.

    http://part15.us/node/1631

    Your clipping trouble is most likely from another effect. I run my SSTRAN (remember it is similar to the Wenzel but not identical) with a base coil loaded antenna which is not similar to the one linked from the SSTRAN site and have had distorted audio and RF carrier. This happens if the antenna is not presenting a proper impedance match to the SSTRAN and for those using the SSTRAN my best advice is to tune the system as per the instructions in the manual and on the antenna website. For a Wenzel system, getting the proper antenna impedance should take you in the right direction.

    Neil

  2. Neil, you are spot on. I
    Neil, you are spot on. I finally got the time to finesse my installation. At 1690 kHz with 108 uH loading coil tapped at 3 turns (less than uH), I get a useable signal for a mile, strong like broadcast quality for 1/2 mile.

    Thanks for your help.

    Macrohenry