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Author Topic: Simple DSB TX  (Read 139 times)

Offline JimIO

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Simple DSB TX
« on: December 02, 2018, 0434 UTC »
What if you took the classic diode ring modulator

https://en.wikipedia.org/wiki/Ring_modulation

and replaced the center taped audio transformer with

https://en.wikipedia.org/wiki/Bridged_and_paralleled_amplifiers#Bridged_amplifier

The BTL amp could be a China TF card MP3 unit and the diodes 1n5817 or simalar.

If it would work you can't get more simple.

Offline redhat

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Re: Simple DSB TX
« Reply #1 on: December 02, 2018, 0635 UTC »
It might work at a few hundred kilohertz, but not much more.  The larger the diodes get, so do their stray capacitances, which limit the switching speed.  I have done the same thing in the past with low level mixers, then amplify it up to 100W pep.  During the peak of the solar cycle, it did quite well.

+-RH

p.s. All mixers exhibit something called conversion loss.  In low level mixers its usually about 7dB...so for 100W pep, you would have to drive the carrier port with about 500 watts....kinda lossy.
« Last Edit: December 02, 2018, 0819 UTC by redhat »
Somewhere under the stars...
WinRadio Excalibur/305 w/ a chi-town resonant loop, Kenwood KDC-U356 for mobile listening.
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Offline Stretchyman

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Re: Simple DSB TX
« Reply #2 on: December 02, 2018, 0935 UTC »
'It's better to give than receive' so why RX when you can TX!

                            Buy one from me, NOW!

Great discounts on ALL my transmitters if purchased via HFUnderground


                                              ;)