Aw: Re: LF: Re: My transmit converter description

["Eike Katzera" <dl3ike@web.de>]

Hi Dimitris,

have you ever thought about using an Class-D-audio-Amp as a powersupply for the Class-E-RF-Amp?

Let the audi-amp follow the rf-envelope an the rf-amp follow the frequency. 

Is that accurate enough to work as an linear-rf-amp for digi-modes?

73s de Eike DL3IKE

PS: what are the correct settings in wspr-software for using split mode in the transceifer in combination with an transverter to prevent data mismatch in the wspr-database? Transceifer RX: 474kHz, TX:10.474kHz

Gesendet: Dienstag, 05. Februar 2013 um 22:32 Uhr
Von: "Dimitrios Tsifakis" <dtsifakis@gmail.com>
An: rsgb_lf_group@blacksheep.org
Betreff: Re: LF: Re: My transmit converter description

> The whole point of this design is that the output impedance is 50 ohm,
> therefore there is no need for impedance transformation! Try
> calculating the values for a 100 V, 100 W Class-E transmitter and note
> the output impedance.


For those not familiar with Class-E, I can control the power output of
a transmitter by the Vcc I use. The power output is proportional to
the square of the voltage, so by reducing the voltage by SQRT(2), I
get half power: 50 W from 70 volts or so. The calculated output
impedance and C1/C2/L2 do not change with scaling the voltage up and
down. That makes class-e an excellent client for amplitude modulation
:-)

73, Dimitris