Yep, you read it right, the transceiver that I gave up on months and months ago sprang to life. I had a feeling that it wasn't dead, my heart of hearts told me that.
So, what happened, and what did I learn? Here's the important thing: There's more than one way to do something. Ben Franklin once said, "I didn't fail the test, I just found 100 ways of doing it wrong," and that's what I did.
With the help of various QRZ.com members, namely KL7KN, I figured out that the receiver can be adjusted with the probing of U2's Pin 1. U2 is an SA602 and is the filter mixer. Probing Pin 1 bypasses the filter circuit, which in essence creates another antenna. The antenna will generate a buzzing or hissing noise. From here, tune L1 and L2 for maximum noise. If you can't hear any stations when you bypass the filter, you still have a problem, unfortunately (once again, thanks A LOT KL7KN!).
I can't tell you how much joy I felt when I began to hear stations when I connected an antenna. It really made me happy when I could hear the FT8 frequency, which means that my tuning was dead on where I wanted it. I could also hear CW stations with ease.
By now, many of you are wondering how well this stacks up to the Pixie. I will tell you that it blows it out of the water completely. The Cub has a crystal filter, an onboard audio amplifier, a great tuning range, and about 2W of output power that can be varied if you want to work QRPp. While the Cub sounds impressive, there are some drawbacks to it. It needs to warm up for a couple of minutes before you transmit so the frequency is rock solid. I also found the alignment to be a bit cumbersome, but that may be because I haven't built a kit like this before. While the audio is acceptable, I feel that it could be a bit louder, but it definitely beats the Pixie's quiet and wide-open receiver any day. For the completed project, I took some photos.
I set the Cub aside and waited to touch up the transmitter side of things until the next day. Turns out, the transmitter side of things was not as complicated as I had thought. In a matter of under 30 minutes, I had a fully-functional Cub, with 1.5 watts of output on 20m.
In addition to this, I built my own 50 ohm dummy load with a wattmeter output. That can be found here: https://www.qsl.net/kc6wdk/QRP/wattmeter.htm. Here is what mine looks like. I do want to note that my copper chloride etchant, used with a nail polish resist, works very well.
To close, this has been an exciting and fun adventure. Now I'm off to build a dipole antenna and perfect my Morse Code! My next test with this is to see if I can show up on the Reverse Beacon Network, or RBN.
If you also want to use the RBN, it's easy! Just send the following in Morse Code:
CQ RBN CQ RBN DE [callsign] [callsign] K
CQ TEST CQ TEST CQ TEST DE [callsign] [callsign] [callsign] K
The RBN looks for CQ calls, so even if you just send out CQ, there is a good chance that you'll show up on the RBN. There are thousands of operators listening on thousands of frequencies and reporting daily. If you know how to send CQ and your callsign in Morse, you'll have no problem showing up on the RBN. It is popular with QRPers in particular since QRP can be a little unpredictable as to where you will reach. Having your callsign show up on the RBN site can give you a generalization of where you can be heard and what you can work.
That's all for now from my shack. Hope you have a great New Year! Until next time...
EDIT 1/2/2023 - Just a few moments ago, I sent out a quick CQ call on the Cub using my EFHW. As soon as I finished sending my callsign, I got a report from the East coast at a distance of 963 miles, which equates to around 647 miles per watt! Not bad, especially for 1.5 watts and a crappy end-fed antenna. I'm off to build my dipole now and brush up on my Morse skills...
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