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Norcal 40a (Was Re: [qrptech] Group Introduction: If you're going to post on the group, reply here!)
On Mon, Nov 11, 2019, at 8:18 PM, wb6ogd wrote:
Thanks Gary for the nice experience report on Norcal 40a. I have got the PCB from Rahul VU3WJM (met him at a hamfest early this year) who, along with Chuck, designed the PCBs for the qrp-tech project with consent from Wayne, the original designer of Norcal 40a. I also have "The electronics of Radio", the book that teaches electronics by building the Norcal 40a. So, it was very hard to pass the opportunity to do a bit of learning and experimentation in the weekend. I am very early into the project. As a first step, I thought of building a G3UUR crystal tester to select crystals for the filter and the oscillators. I have got about 100 4.9152 MHz crystals that I got from aliexpress. Last weekend I built the G3UUR Colpitts Oscillator (straight out of the EMRFD book and also described in many other webpages). I also have a counter with a 1 Hz resolution, again obtained from Aliexpress specifically to hook up into the Oscillator. Unfortunately, when I plug in the 4.9152 MHz crystal, I get a reading of 14.742475. Looks like it is 3x the frequency of the crystal. I tested many from the lot of 100 crystals, which came in lots of 50 from two different vendors and they all read the same. I had a 28.04 MHz crystal which seem to be oscillating at the correct frequency. I don't know what to make out of these readings. Is the crystal, a 3rd overtone crystal? Or is it that the colpitts oscillator is designed to operate at a higher frequency and the 3rd harmonic is where the tuned circuit that comprise the crystal (which is inductive?) and the two capacitors are getting tuned? The Colpitts Oscillator base-emitter capacitor (C1) and Emitter-Ground capacitor (C2) are both 470pF. That value seem to be a little high for lower valued crystals. So, that is where I am at with the Norcal 40a. As for building the project, Chuck has some excellent videos on YouTube. I plan to build the receiver first (backward, from audio section onward) and then the transmitter. 73 -- Ram VU3RDD |
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Re: Group Introduction: If you're going to post on the group, reply here!
New member here, I wasn't on the old list, just saw a blog post that it had closed and this was replacing it! So thanks for creating this, there's still a lot of interest.
New to homebrew and QRP (and recently back to radio), but its always interested me, ever since finding out about ham radio and visiting a QRP CW operator in Wales as a 12 year old. Hoping to learn a lot. Should be slowly accumulating the equipment to actually build and test over the next few years. Tristan KJ7FWK / M3MQG |
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Re: Group Introduction: If you're going to post on the group, reply here!
On Sun, Nov 10, 2019 at 08:57 PM, Ramakrishnan Muthukrishnan wrote:
Hello Ram and the new group, Two years ago on Chuck's old group he started the NC-40a project.? Many of us built the rig and I really like mine. Yes, this group should do some group builds again.? I was getting excited by the 2Nxx everyone was talking about. I googled it and that killed my enthusiasm.? That rig looks like an amazing piece of engineering, wish I could design something like that (but no way!).? 300 parts on a really tight PCB is pretty crazy, would not be a beginners project for sure. You guys who now can not get a PCB for that project should take a look at the NC-40a.? It uses ICs, that's a good thing!? It might not have the receiver specs of the 2Nxx but it is fine for a qrp 2-3watt rig.? Chuck or the group found a great deal on chinese PCBs back then, something like 10 boards or $5 shipped, MANY of the boards must still be out there, many nice guys will probably share some of their extras.? Or the gerbers do exist, hopefully you could get them and order more boards.? I designed my own board over a weekend with free ExpressPCB software and home etched my own board, it was a very rewarding and successful project.? My board used mostly SMD which I find much easier than through hole, I can give the design if anyone wants it. The NC-40a has two good features I don't see in the 2Nxx (I might have missed them): AVC and Sidetone.?? These are really needed I think, and the sidetone is actually your transmitted signal so you know if it sounds correct and has the right offset, etc.? Mine puts out 3watts with a 20cent Chinese final that doesn't even need a heatsink. Think about it, 73, Gary WB6OGD |
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PCBs for NorCal 2N2/XX Rig
¿ªÔÆÌåÓýFor anyone who didn¡¯t see this on the 2N2 Group or original qrp-tech group ¡. ? Cheers ? Michael VE3WMB ? From: NorCal_2n2@... <NorCal_2n2@...>
Sent: Sunday, November 10, 2019 5:54 AM To: [email protected]; norcal_2n2@... Subject: [NorCal_2n2] PCBs for NorCal 2N2/XX Rig ? ? All, __._,_.___
? ? Unsubscribe ? . __,_._,___ |
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Re: Group Introduction: If you're going to post on the group, reply here!
Ram VU3RDD from Bangalore, India. I enjoy QRP and homebrew radios. Currently operating with a ?Bitx and have 80m and 40m antenna. Sadly no 20m yet. Currently gathering parts to build a Norcal 40a. I will make a separate post on this later. It would be nice if a bunch of us get started building projects as a group again. 73 -- Ramakrishnan VU3RDD |
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Re: PCBs for NorCal 2N2/XX Rig
That's too bad, but I understand Jim's reasoning. However, as he said, the info is all there for the taking.? I wonder which parts he's talking?about not being available anymore? I took a quick look through the schematics and didn't see anything that looked like it was made of unobtanium.? It does look like a fun project. I have a little experience with Kicad, but I don't think I could pull this off by myself.? 73 Mike M. KU4QO On Sun, Nov 10, 2019 at 12:50 PM Leland L. Bahr <w5drc@...> wrote:
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Group Introduction: If you're going to post on the group, reply here!
¿ªÔÆÌåÓýGary W0ITT checking in.? Thanks for the group. ? ? 72 de Gary W0ITT ? Sent from for Windows 10 ? |
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Re: Group Introduction: If you're going to post on the group, reply here!
Thanks Ryan
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73, Jim N2JJ -----Original Message-----
From: Jim Smith <g3zqc@...> |
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