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Spectacular! I enjoy Hans stories at least as much as his products! 73, Willie N1JBJ

Hello all, My newly-built QMX does not draw any current and, of course, does not turn on. When I press the power button, the DMM on the current setting reads -.23mA. Here is what I've checked so far:

My fix for trifilar windings is to use different colors of enameled wire. Within reason, you can use different sizes of wire, too. Oscillator coils from old television sets are an excellent source of

General statements about components: 1. Identify the environment they must work in. (temperature range, shock/vibration, altitude, space or automobile qualified, etc as necessary 2. Identify the

I totally agree with Hans here on the L401. Deleting the band pass filter in QMX would, IMO, ?probably turn it into a uSDX! With all the respect to their unique design disclosing the Atmega

Hello group. This is my first post--wow, reading this list is akin to "drinking from a fire hose". Two weeks ago I purchased a QMX kit to use as a WSPR beacon during the eclipse challenge event. The

look at https://www.farcircuits.net/rf_amplifiers.htm Drop down to the Mousefet amplifier board.? This is a Class C amp from way back? which has a 2n3866 preamp built in .? I think Fred's version

Hi Jim It doesn't seem that the connection problem is related to the QMX itself. Something on the mac or in that particular software. Another thing to bear in mind, which could be a misunderstanding

cw mode received transmission current is still 0.1A, no change, but there is transmission code under cw, 555 kilometers away websdr can clearly hear, but the current is still 0.1A, I need to check

Hello Damion Thank you ;-) Current draw will be higher at lower supply voltage, as is characteristic of SMPS buck converter systems. However if you are saying 140mA is at 12V supply, which I assume

I found an analysis of tantal dish capacitors ( https://www.utmel.com/blog/categories/capacitors/various-reasons-for-the-failure-explosion-and-burning-of-tantalum-capacitors ). It's worth reading and

Hello brains trust, Well firstly, on the assumption that Hans will read this - well done on an amazing design.? The more I learn about this radio the more impressed I am. My status is overall pretty

Hear hear, THANK YOU, great idea Ted... I think adding an #experimental tag to the topic subject line would be a great way forward; that way we can continue to encourage and learn from all the

Hi all Thanks to Muhsin TA1MHS for sending me the attached page 9 advertisement from the latest Nov 2023 QST magazine. Since some of you guys love a good story, pending the maybe-someday-forthcoming

Experimentation is at the heart of amateur radio. Like any science, that's how we find stuff out and twist our brains into different perspectives. Observe - hypothesise - experiment is how I was

Joe, with this entry you are telling everyone that DHL is a bad supplier. Then you post another message that it's not DHL, but Fedex. If you only read the addresses, you will come to the conclusion

Hello Aaron The BaMaTech enclosure was for the original QCX Classic that I retired in 2020 when I launched the QCX+. If you have a QCX+, the BaMaTech enclosure won't fit. If it's the QCX+, then the

Hi, I agree totally that the BPF is needed here. Even more selective if there would be room for it. Strong signal will be demodulated at the first non-linear element in the receiver front-end, the mux

I built my QDX a few months ago and it passed all the standard tests with flying colors. IIRC, I saw 4-5w on all the bands I tested, using my MFJ QRP power meter. I built it for 12v, and haven't

Hello Ryuji You are correct about average to peak power ratio. But this isn't the point. The point is that there are sophisticated RF Power meters that do thermal stuff or measure r.m.s. Then there