[Lowfer] Hell 137.58 Khz

[Jay Rusgrove]

Tom

Thanks for the report and captures. Nice copy!

Actually, generating a 400-watt cw or QRSS signal is very easy with a two FET Class-D amplifier like I'm using. Power supply requirements are a modest 50 volts at just under 9 amps. Efficiency is close to 95% so a small heat sink is sufficient. 

For modes that require a linear amplifier John and I are using audio amplifiers...the Hafler P3000 (good for about 250-300 watts out) or the 9505 (good for up to about 750 watts out) and the setup is essentially 'plug and play' with the addition of the input and output interface devices...and a few muffin fans. This setup can also be used for cw and QRSS but at lower efficiency levels.

Perhaps the biggest stumbling blocks for most hams would be the high currents and voltages associated with small antennas. Many EU stations with small antennas run 1000 watt amplifiers so it can be done. With a few precautions you're not likely to burn down the neighborhood ;~)

Thanks again for watching.

Jay