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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%

Hello Brent... I'm thinking about the same approach, using the QRPLabs LPFs. I'm only interested in 40/30/20/17 for now so I bought LPFs for those bands along with the relay board. I have them all

Indeed, this does show that the attenuation pads used between the Si5351 and the various transformers at the mixers on the uBitx have too small a load resistance for the Si5351 clock outputs. Note

Thanks Jerry I was thinking of taking Allison's advice and either using the existing parts on a new board, or getting the qrp-labs kits and relay board, and use 60m low pass for 80/60, 30 m for 40/30,

Thank you very much, sir. You just made my day now that you said this.

I rolled the dice on a pair of filters and received Toyocom 45E1A9Fs which show up here https://www5.epsondevice.com/en/information/discon/pdf/21j1f_e.pdf as two pole filters at 1200 ohm termination

Warren, The problem is the balanced mod easily takes that but the gain after it means the 2nd mixer gets hit with a very high level.? With that the output of that mixer is high and that leads to the

Now that I know how to make one, I like doing that if I’m going to do digital. Common mode and unbalanced currents wreck havoc with digital systems. But for the first 35 years that I was a ham, I

Oh, thanks! I'm looking for an SWR-meter meanwhile. And about the balun ? Is it a "MUST HAVE" ?

Get an SWR meter. old CB types work fine. $15 Most people use 50 ohm coax , but even 75 will work fine. Make a dipole, test the swr, adjust as necessary That’s how many of us started out over the

Actually - that makes a lot of sense Raj b/c the two ends of the filter seem to be capacitively coupled internally according to the spec sheet. It would be great to see the ultimate results of that.

I searched for this problem to no avail. So I am posting in case someone has an answer. I bought a new uBitX, and installed it in the case from Amateurradiokits.in. Upon powering up the display shows: