For the last few weeks, as time permitted, I have been working on building a 40 Meter Transceiver kit. The kit is called the 2n2/40 and it is kitted by the Norcal QRP Club (click). They make great kits at very reasonable prices. Since this is a labor of love for them, they do all of the development and kit production for free and sell everything at cost. They have temporarily suspended taking new orders, but I understand they should begin accepting new orders in the next week or so. The kit is available in 40 M, 30 M and 20 M versions – I ordered the 40 M version.
The kit designer is QRP legend, Jim Kortge – K8IQY. Jim perfected a circuit board building technique called Manhattan Construction. Rather than etch circuit boards and drill holes, the builder uses small islands of circuit board material and glues (Crazy Glue) them to a blank circuit board. The connections between components are made on top of these “islands” by simply bending the component leads so that they stand upright (so the board looks like downtown Manhattan, I guess). You solder the leads to the islands. You can see an example of this construction technique here (click). You've got to see these pictures to appreciate the simplicity of this technique and Jim's craftsmanship. Jim has designed a whole series of rigs around the venerable 2N2222 transistor (the cockroach of the solid state world). The rigs perform as well as store bought rigs costing hundreds, if not thousands, of dollars (except they are CW only and top out at 5W).
However, K8IQY and Norcal have teamed up to produce these kits using traditional circuit boards. Now you can stuff a traditional circuit board, solder some leads and build one of Jim's rigs cheaper than you could order the parts yourself.
The assembly manual (online at the Norcal site) is every bit as good, and simple, as one of the old Heathkit manuals. However, that has not stopped me from making a few mistakes as I go along. Did you know a circuit is not likely to work if you install the diodes backwards, or put the wrong resistors in the right holes (or is it the right resistors in the wrong holes)? But the Norcal manual provides easy testing procedures at each stage of the build, and there is a very supportive Yahoo group where K8IQY lurks to help you with troubleshooting problems. I have completed the receiver portion of the 2N2/40. Here is a picture of the circuit board with the receiver strip completed (some controls are temporarily tacked in right now – awaiting their home in the cabinet). Now, on to building the transmitter portion!
The receiver is very sensitive and the audio is good and strong and rock solid. I think I'm in love.
UPDATE: I just saw that Norcal is once again accepting orders for the 2n2/xx kit. It's a limited run of 500 kits.
Brad - WA5PSA
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3 comments:
That is super-cool. I bet it feels good to know you "made it yourself". Do you feel like you understand how it works ? Did the instructions come with a "theory of operation" chapter ?
73
Scott
KD5NJR
No "theory" chapter, but the detailed testing and alignment procedures in the manual sure give you a feel for what's happening at each stage. Also, if you have any kind of question about how something works, K8IQY is very good at patiently answering questions for the tech-impaired (like me). He's a great teacher.
Yes, it is cool to hear signals coming through some headphones, knowing that I built the thing. It adds some extra magic into this already magical radio thing.
I just saw that Norcal is now allowing new orders for the 2n2/xx kit.
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