Am 28.12.2013 23:33, schrieb Markus Vester:
[...]
PS Any progress on bypassing the
divider in your VLF transmit chain?
Aaah, no, i forgot that. So i cannot transmit OP32 on VLF because it
would be incoherent then. So i have to key the PA via a VOX and OP32
tones, still :-/
In this H bridge PA config, an exact 50% duty cycle isn't needed, so i
may actually remove the divider. But then i need a solid and defined
input signal wave form! How do i get an inverted signal then? A
transformer isn't possible since i like to have a wide frequency range
of the PA. So far it works from 10 Hz to > 100 kHz. With the
frequency divider, the wave form can be quite distorted, no problem
unless the peak reaches the necessary voltage level. So maybe it is
better to build the VOX circuit instead? Also i want to leave the PA
circuit as it is, for nostalgic reasons :-)
Or do you have another idea? I remember that circuit with the XOR
gates...
73, Stefan/DK7FC
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