Sujet : Re: 80dB now but still needs improvement at 1KHz [OT]
De : alien (at) *nospam* comet.invalid (Jan Panteltje)
Groupes : sci.electronics.designDate : 08. Nov 2024, 14:34:33
Autres entêtes
Message-ID : <vgl419$l989$1@solani.org>
References : 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
User-Agent : NewsFleX-1.5.7.5 (Linux-5.15.32-v7l+)
On a sunny day (Fri, 8 Nov 2024 12:41:18 +0000) it happened
liz@poppyrecords.invalid.invalid (Liz Tuddenham) wrote in
<1r2peuv.72nzt16pvcxmN%
liz@poppyrecords.invalid.invalid>:
Jan Panteltje <alien@comet.invalid> wrote:
>
[...] >
https://panteltje.nl/pub/audio_90_degrees_phase_shifter_circuit_diagram_
IMG_6958.JPG
>
Thst is a 90 degrees phase shifter over the speech audio range for
generating I and Q signals for SSB modulation. design is not mine, used
trimpots to test it :-)
>
After reading through some back issues of 'Rad Com', I had been thinking
along similar lines for generating SSB. I was also intrigued by the
Weaver method and wondered if modern multi-stage filters between the
inverted and non-inverted audio sidebands could reduce the audio notch
effect and allow a wider frequency response.
In teh sixtoes I used a 9 MHz IFto make double sideband with a diode brige modulator
and and a XF9B crystal filer to remove the unwanted sideband
Had no license back then, all tubes, 250 W SSB with a Philips PE1/100
https://www.radiomuseum.org/tubes/tube_pe1100.htmlMade QSO with a callsign I dreamed up..
Was almost arrested, they were at the corner of the street locating me..
Few years ago I got the A license, thought it was only fair as I was using stuff from ham radio
https://panteltje.nl/panteltje/raspberry_pi_dvb-s_transmitter/and basically wanted to keep up with digital TV (when I left broadcasting it was still all analog).
My license is still extended every year.
But am not very active, have a Baofeng for 70 cm and some RF transceiver for shortwave.
And the satellite stuff of course.
But I will have to move the dish, after the cross the street houses had their roof insulated those became a bit higher and
have their roofs filled with alu foil I think, I lost signal from the QO100 geostationary satellite....
I let my licence lapse many years ago and had been thinking about taking
it out again before the call-sign got issued to someone else. The
problem is that they need to see my certificate to prove I passed the
Radio Amateurs' Exam and I don't know where to find it.
Well I have mine hanging on the wall, and keep some diplomas in a map somewhere.
Also, in case of emergencies when all networks break down I can perhaps help using radio.
Have enough backup power for that.
There is a lot more...
Have some old CB 27 MHz stuff too, CB was still licence free, worked South America on CB from here.
It is a fine line, video from my drone's camera, who needs a license...
https://panteltje.nl/pub/the_village_0_degrees.png https://panteltje.nl/panteltje/quadcopter/index.htmlNow you need a license here for a drone above some weight...
And I am not allowed to fly a drone here at all as I am now close to a mil airport...
A web of legislation... forms .. over time.
80dB now but still needs improvement at 1KHz
Re: 80dB now but still needs improvement at 1KHz