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Finished the assembly and started the tuning and adjustments. Connect power -- No Smoke! Adjusted contrast -- OK Started at step 3.71 Did the "Select Band" step, OK Pressed "Left Button", OK Pressed

Hi Todd Yes... true! But the topic was DSB not AM or a comparison of every other possible mode and how efficient it is and various other advantages and disadvantages... Yes AM is inefficient and

Hans, A very nice, well thought out description of DSB, especially relating to FT8 or similar modes. I have never used DSB for any "on the air" experience, but assumed the appeal is strictly for

The short version is two DSB with non SSB RX is, works very poorly. Reason is the two opposing sidebands are sent and are also received. The result is they combine and partially cancel each other in

If only someone would code up a version of WSJT to do just this. Mike K6ESS

FT8 is a constant amplitude variable phase modulation. It can be generated without any filters using Si5351 or other programmable synthesizer chips, and amplified using efficient class C PAs. A

"...it is difficult or impossible for two DSB stations to work each other." Hans, I'd heard about this in the ancient past but never paid much attention to it. Can you provide a technical

Guys, I have a Wilderness NC40A I can put on the air if someone wants to work Louisiana. I am also usually available in the evenings CDT. 73 - Dave, N4ELM

Thank you Hans and Todd for so clearly expressing the concerns I have about using DSB. I'll confess to having built a DSB transmitter that I have stared at, and never quite been reckless enough to

Hans, Your anti-vax anti-social analogy is quite apt. I don't understand the allure of DSB (or the superstition against vaccines, for that matter). If one is going to suppress the carrier, why not

Hi all In my opinion... I don't care about the boring legal aspects... purely technical: 1) DSB is something of an abomination in that it is difficult or impossible for two DSB stations to work each

Tom, It takes 4 crystal at a counter price of about 50 cents and 4 capacitors at pennies to make such a filter then you have whats called a SSB radio. It was done by K1SWL (PSK-80). It was a

I'm probably showing my naivety and lack of technical knowledge, but I have been wondering why all the discussion has been focused upon the legal aspects of whether this combination of emission (DSB)

John, That sounds great! Though I have discovered an issue with my 40A, receive is about 1.5 kHz off my transmit frequency so I have a (hopefully easy) tweak to make to get the radio in shape. I will

Michael, the antenna is up and the NC40a is working FB - I'm planning on using it a bit in the upcoming CQWW contest. Let me know when a sked would work for you - any evening after 2330Z works for me

I ran some simulation of the power recovery circuit in ltspice. With the assumption, that the controller driving the LED baragraph draws 1.2mA at 2.4V, the following peak currents of the power

Maybe some of you have had this same problem. After about a year of non use, I fired up my Feeltech FY3200S and was greeted with a lit-up but otherwise blank LCD, and a constant howl from the on-board

I largely disagree. First how your transmit digi and what mode is partially due to band plans. If your transmitting a DSB signal in the CW segment of 40M thats not cool. do it higher in the band then

That's an interesting take on the issue, but I'm not sure I agree. As far as I know there's no FCC (for USA hams, anyway) rule against transmitting digimodes in DSB (or AM, FM, or ISB). It's not

Using DSB modulation to Tx a FT8 signal means that you will end up transmitting a second FT8 signal a few KHz away from your intended one. From what I understand, this will have legal issues also with