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Kees, The diode mixer needs a non reactive, 50 ohm match on the IF side. If this is not so, it will generate distortion and birdies. That's one of the two purposes of the bidi amp. Directly connecting

So ..Thinking of this and that ...Came to the blinding revelation that the IRF150 is NOT a current controlled device, but a voltage controlled device ...With that in mind, I bypassed the main current

Ah, Siri! That was supposed to be the most wire, not the most water!

Ricbard, you might consider a Magnetic Loop. It will be hard to get high efficiency on 40 metres, but at 20 metres I have had success with a 1 Metre diameter MFJ loop and 10 watts. If you have a large

Timothy, that book from the ARRL is extremely nice I think Alyson summarized how to get the best HF antenna, given whatever situation you’re in: but the most water, the most clear of attenuating

I would recommend putting the voltage regulator in the supply line to the TDA2822.? I did that before applying power to my kit and have not had a problem since then.? I have very high volume levels

Tom, Go back and read what I've posted.? Any load that creates a current flow increases the crosstalk. Using a CMOS buffer with minimal capacitive loading to the 5351 as we want NO current flow.

Great find!? That information is not in the most recent datasheet.? Current limited output buffers would explain a lot.? However, having a low Rload with current limited outputs would mean slower

I would try any of the mobile whip antennas mounted to the balcony railing and use a quarter wave wire spiral wound on a 4'X4' wooden or PVC frame as the counterpoise.? Just notch the frame to wind

Allison, I agree with everything you have said here. I really don't have anything new to offer at this time. I've moved on to other, more pressing projects. Perhaps I'll get back to the ubitx as the

Yep! That's the whole point of a single point ground! Run the negative lead from the radio to the battery! tim ab0wr "iz oos" <and2oosiz2@...> wrote:

Here is a slightly older revision of the Si5351 data sheet before some marketing person possibly demanded that the data sheet had too much technical gibberish and scary numbers in it, and that needed

Richard I would see what HF antennas might fit on or next to your largest window. A dipole with ends bent, or a moxon come to mind. Try to google high rise indoor antennas for ideas. You will be

Great questions, a ham license is an opportunity to keep learning. Good answers here. Best to get 50 ohm coax, but as others suggest 75 ohms will work. I have never used a balun on a dipole. You can

Daniel Great questions, a ham license is an opportunity to keep learning. Good answers here. Best to get 50 ohm coax, but as others suggest 75 ohms will work. I have never used a balun on a dipole.

On the assumption that leads to a buffer board out of the Si5351 outputs being a good idea, I drafted one up that fits onto the uBITX board as shown.? Requires 3 track cuts on the uBITX, pcb is

I live on the 38th in Toronto and I don't have a balcony what do you suggest I use for an antenna. Richard

Dan, for QRP work, a balun is not that necessary. A balun helps greatly in reducing common-mode current that can be created on your feedline as a result of feeding a balanced antenna (dipole) with an

Hi, Welcome to ham radio and the microBitX. Much of what the others have told you is spot on. I only want to point out that a dipoles is close to 75 Ohms when it is high above ground in terms of

FWIW, I have often used good quality and inexpensive rg6. If you want, you can even use a pre-made 50 or 100 ft length, and then buy some pl259 to F or bnc to F adapters. Although maybe? not 100%