Trevor Woods found this report from Arnie Coro (SK) CO2KK:
February 2009:Here is now item three in detail: It was quite a long time ago, when I heard about a nice project sponsored by IARU, the International Amateur Radio Union, that was promoting the design of a kit, a simple single band transceiver kit that could be sent in a small air mail parcel to radio clubs in Third World nations which could then deliver them to would-be radio amateurs, and help them build and align the radios... But, unfortunately I lost track of the project, and as many of our listeners may realize there is still a great need of such a project... Past efforts along this line have had some problems, among them the mistaken approach of using of very sophisticated electronic components that in case of a breakdown would be impossible to replace locally; and also, all attempts seemed to try to make the transceiver an ultra- or near-ultra-miniature radio, something that won't help at all with beginners...
So, when I recenlty received an e-mail from Canada, asking what I thought about reviving this great idea, our Canadian amigo asked what we had already done here in Cuba, with our JAGUEY double side band plus CW 10 watt transceiver that went up to REVISION NUMBER 5. , This was the last upgrade, done about three or four years ago, and we named it the Jaguey FIVE, as it generates 5 watts of CW... The Jaguey FIVE was a low parts count, not miniature, easy to build single band transceiver that used readily available components, instead of sophisticated state of the art parts...
In order to please the friend who wrote about this topic, here is a brief, on the air, description of our Jaguey FIVE and by the way, Jaguey is the name of a town, actually it is Jaguey Grande, or big Jaguey, and the Jaguey is a beautiful tropical tree... The original Jaguey transceiver originated in that Matanzas province town in 1982,
The receiver part starts with a simple yet effective RF attenuator, then it feeds a bandpass
filter made of two tuned circuits... we use shielded IF transformers from old TV sets 4.5 megaHertz audio chains... A simple bipolar NPN small signal transistor grounded base amplifier feeds a homebrew double balanced mixer... and we "discovered" quote, unquote, that the antenna balun transformers used in TV sets, the 300 to 75 ohms baluns, had a ferrite core with two holes that makes a wonderful broadband transformer for the double balanced mixer...
We use computer diodes removed from defunct ISA old computer cards and motherboards and developed a very simple test jig to match the diodes... The double balanced mixer is fed on the other port from a simple three transistor oscillator, of which we have two versions, one using three NPN bipolar transistors and the other one using an FET oscillator followed by two bipolars... at the output of the mixer we have AUDIO, as this is a direct conversion receiver, amigos!!!
Now we amplify the audio using discrete components and again we have two versions of audio filters, one with bipolar NPN transistors and the other using a very common operational amplifier IC... The audio power output stage also is available to the builder in two versions, one using discrete components and the other using an integrated circuit audio amplifier that is locally available here in Cuba and produces a booming 2 watts of audio, with a lot of gain and rather low noise! This is the audio IC used by the most popular TV set in use here in Cuba, so we were able to obtain them from the TV repair shops at low cost.
Well, that's why I will describe as a flexible design... again, no attempt is made to make the Jaguey single band amateur transceiver a miniature rig, as miniaturization is definitely not for beginners!!! And following up this description of the receive section of the Jaguey, in our upcoming mid-week edition of Dxers Unlimited, I will describe the transmitter section of the rig,that shares the same variable frequency oscillator with the receiver.... I think that a new more up to date version of the Jaguey transceiver could very well be made available in kit form, with large-sized and easy to assemble circuit boards. The old Version 5 uses three circuit boards, one for the receiver, one for the VFO and one for the transmitter, so the newcomer can assemble just the receiver and start listening to amateur radio communications before having his or her own ham license!!!
You are listening to the weekend edition of Dxers Unlimited coming to you from Havana on the air and on the web at our Dxers Unlimited blog.
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A video of Jaguey Grande, Cuba: https://www.youtube.com/watch?v=krblz_5o6jU
Earlier posts about the Jaguey on the SolderSmoke blog: https://soldersmoke.blogspot.com/search?q=Jaguey
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