not that anyone would particularly care and might not understand the technical aspects of this, but i thought id share some specifics about my HF station in case there are inquiring curious minds.
the transmitter is a Yaesu FT-757GXII, chosen for its simplicity to modify.
it is completely modified by me for full audio spectrum on AM only, from DC to at least 20Khz (70% power drop at 20Khz sine 0dB).
i also modified the unit for better carrier and peak envelope power output, 50 watts and 200 watts PEP respectively, power output is adjustable.
the cooling circuit of this unit has also been modified and improved for full duty operation using a linear 20 amp power supply (which is also cooled) operating at 15VDC.
the RF output travels through LMR400 at 100 feet to a 3 wire matched dipole for 5.150Mhz (modified bushcomm brand).
the height of the dipole antenna to the ground radials is specifically set to provide 60% angle of RF radiation for NVIS and 40% at a near horizon angle.
the audio processing is performed by "stereotool" (excellent software audio processor) on an Asus windows 10 netbook using a virtual sound card for the input and the headphone jack output matched at 75 ohm line level using shielded 75 ohm cable connected to the transmitter, the audio bandwidth is currently set at 5Hz to 5Khz as most self contained radio receivers besides SDR's have filters set at 5-6 Khz.
the netbook is remotely controlled using "Team Viewer" which can be used on any device including smart phones.
the transmitter also has thermal, VSWR, current and voltage shutdown protection that i added.
the frequency 5.150Mhz was chosen after extensive research prior to using it to be certain of its assigned status in the USA.
i cant think of anything else but if anyone has questions, ill be happy to answer them
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