Here's a quote from Wes describing the equipment that he was using on his end:
I hope that my signal was OK when we worked. I was in the midst of wrapping up a frequency synthesizer project and had it running on the rig for the first time. When I heard you on 20, I could not resist calling. You were the first contact using that source. But I then discovered that the PLL was oscillating. It was a low level oscillation and didn't present an obvious problem with regard to what I heard on the air. But it was there. I have since then changed the phase/frequency detector circuitry and have eliminated the oscillation. I am not thrilled with the 74HC4046. I get much more repeatable performance from a dual D FF with a NAND gate.
I feel pretty guilty that I've let the blog content slide in 2011. As you can imagine, between having a near-toddler cruising around the house, doing a major redesign of a QRP transceiver, and trying to bootstrap a new small business, free time is at a premium (and my wife and kid owns what little there is). The least that I can do is give you a quick glimpse into the progress with the radio.
If you don't follow me on Twitter, you probably don't know any of the details of my progress with the CC-Series radio. After advancing the design of the radio to a point where I thought it was production-ready (two PCB turns, lots of design review and tweaking), I ended up failing pretty miserably in the end. The problem was with a subtle, but noticeable pull on the free-running VFO on transmit (which was not present on the prototype). I spent close to 2 months attempting to troubleshoot that one little problem, but sadly it ended up defeating me. Perhaps "defeat" isn't the correct word. There was a part of me that wanted to keep stubbornly trying until I tackled the problem (ask poor Jennifer about my stubbornness). But I had to look at the issue realistically, from a business point-of-view. I had no idea if it would take me a few more days or many more months to solve my problem. So in the interest of trying to save my fledgling company, which hasn't even made it out of the nest, I made the difficult decision to temporarily abandon the CC-Series development.
Instead, I decided that I would take on a similar project: revamping my minimalist entry in the 2010 FDIM Challenge (the 72 part rig). It started as just a few upgrades, but quickly spun into a new project of its own. When the VXO scheme that I wanted to try didn't work out as I had hoped, I decided that I would bite the bullet and add a DDS to the project. I planned on reworking the CC-Series with a DDS anyway, so this would be a good way to learn how one works. In order to make the rig worthy to be sold to other people, I kept incorporating changes and features from the CC-Series. I also leveraged my firmware from the CC-Series, which made it easy to get up to speed with the new radio fairly quickly. By now, the rig resembles what I intended the CC-Series to be in the first place.
A few nights ago, I made my first QSO with the rig with W7GVE in AZ. We had a nice little chat and he let me know that I had a little bit of chirp on my signal. Right after I signed off with Ed, I got a really pleasant surprise. Who else but the great father of us QRP homebrewers, W7ZOI! He dropped in to give me a quick "hi" when he heard me on the QRP watering hole of 14.060 MHz. According to my (admittedly incomplete) log on my PC, this was my first QSO with Wes. It was a great thrill, but unfortunately I missed about 25% of his transmissions because I was too nervous to copy CW well. I fully admit that my CW is still lousy, and my comprehension drops off the cliff when the other guy is going greater than about 15 WPM and I'm jittery.
I made some tweaks to the transmitter (and torched some finals in a spectacular, fireworks fashion), then managed to make a sked with one of my partners in crime, AA7EE. It was a rough QSO, especially for me, but we exchanged signal reports so it counted (20 meters at 2200 local on a short path between us is not conducive to communication). Better yet, Dave reported that the signal was rock-solid and chirp-free.
So where do we stand now? I want to do a little more on-the-air testing, then I'm going to start laying out the PCB. The last time I ordered prototype PCBs from my vendor, they were very high-quality, but the turn around time was less than desirable (nearly 3 weeks). This time, I'm going to see if I can lay out the board with minimum vias (probably not going to happen). If I can do that, I might be able to make my own board with the toner transfer method. If not, then I'm going to look into a vendor that can give me boards with more alacrity, at least for the prototypes.
It's been frustrating, but it's also forced me to refine all of the circuits in my radio in order to make them as bulletproof as possible. As long as I can get this puppy to market, then it will have been worth the heartache.
Last night, I had another QSO with AA7EE so that he could record my transmissions and send me back the recording for evaluation. We had talked about meeting sometime after dinner, but set no specific time. Right around 1900 local, I fired up the rig on 14.060 MHz and was just getting ready to send a tweet to Dave to see if he was around. Within about 30 seconds of turning on the rig, I heard someone calling CQ on the watering hole frequency. Sure enough, it was AA7EE. I established contact and we had a quick little chat. Thanks to Dave's generosity, I've posted his recording of the QSO below. The QSB was bad on my end, but as you can hear from the recording it wasn't very bad on his end. Even though the signal was weak, the note from the rig sounds clean, stable, and chirp-free. Be sure to stick around to the end of the recording for a few moments of commentary from Dave himself.
Things have been a bit quiet on the blog front as I work to get the CC-40 beta up and running. Last month, I had an initial set of beta PCBs manufactured, but I made a really big mistake. Somehow I bungled the footprint of the ATmega168 microcontroller, and it ended up much smaller than it should have been. I managed to wire the microcontroller to the PCB using 30 AWG Kynar, but another problem manifested itself. The wires acted like an antenna and radiated the 16 MHz clock all over the board, causing a high pitched whine in the audio. I continued to build the board, and for the most part, the rest of it worked as expected, but I couldn't release a board with such an obvious fault to the beta testers. It was probably a good thing that I was forced to spin the board again, as I found some other subtle problems that needed to be corrected. The new PCB design was submitted to the PCB vendor early this morning, and with any luck the new board will be here in about two weeks.
The current beta test unit is still usable, especially if I hook it up to my external AF amp, which cuts off high frequencies pretty well. Early this morning, I shot a video comparing CC-40 to my SW-40. I'm listening to JA1NUT and manually switching between the CC-40 and the SW-40. It's not a great indicator of the performance, but at least it will give you a little taste of the character of the radio.
While I wait for the new beta PCBs to get here, I've still got plenty of work to do in preparing documentation, setting up my shipping station, and getting my web shopping cart configured. We're also going through the fun of Noah teething, so sleep is at a bit of a premium for us at the moment. With any luck, the next update will be some happy news about how the new beta PCBs work great!
I'm pleased to announce that I've filed the appropriate paperwork, and that my new open source amateur radio company is born! The logo links to the new domain, but there's nothing on the web yet.
I've also given "Project X" a proper name. It's now going to be known as the CC-series of transceivers (with the current 40 meter beta units being CC-40 models). The beta PCBs are in the process of being manufactured, and are due to get here by the end of January. Once the boards come in and I can build a working beta unit, the real beta test will be on; with any luck by early February. It's not quite as fast as I had hoped for, but you can't rush certain things.
In the meantime, I'll be working on getting the online store functional and navigating the maze of bureaucracy to make sure that I don't run afoul of some obscure regulations and get shot down before I even take off. The blog updates will pick up again once the beta testing gets going.