Dave Richards AA7EE

February 10, 2016

The Muppet-Style Construction of John N8RVE

I have been meaning to write a post featuring the inspiring construction work of John N8RVE for almost a year now but sadly, am only able to think about one thing at a time, and The Sproutie MK II took up a lot of space in my head last year. Then, after finishing that, my one-track mind switched off from home-brewing and blogging activities completely. I am still unable to contemplate any more construction projects, and think that I may have done everything I set out to do with home-brewing, at least for a while.

In the meantime, there are a couple of things I’ve been wanting you to know about, and one of them is the excellent approach that John takes with his projects. John and I first became acquainted when he built a Rugster direct conversion receiver, and a WBR. Then I saw his build of a broadcast band regen, and that classic QRP design, Dave Benson’s SW+40, and really started to take notice.

John uses a form of construction that has been championed by Chuck Adams K7QO, in his QRP-Tech group on Yahoo Groups. Chuck calls it Muppet Construction and it refers to the practice of using an etched PCB, but soldering the components directly to the copper traces, thereby negating the need to drill holes in the board for component leads. It makes the process of creating the board easier, as there are no holes to drill. Also, after the circuit has been constructed, it is easier to look at the component side of the board and figure out what is connected to what – a process that is much harder with conventional through-hole PCB’s.

Back in January of last year, John finished construction of a broadcast band regen receiver, based on a design by Rick Andersen KE3IJ. Here is his very nicely etched “Muppet” PCB –

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BCB Regen Receiver (Photo courtesy of John N8RVE)

The board partway through construction –

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BCB Regen Receiver (Photo courtesy of John N8RVE)

And the completed regen (note the use of a rubber pinch wheel to achieve slow-motion tuning –

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BCB Regen Receiver (Photo courtesy of N8RVE)

John’s next project really caught my attention. It is the classic QRP design, Dave Benson’s SW40+. Dave has retired, and the SW40+ is no longer available as a kit (perhaps sometime in the future it will be again?) I’m sure there are many folk who would love to build a SW40+ but lament the lack of availability of a kit. Luckily, the kit manual, including schematic, is freely available online so the obvious answer is to build your own, which is exactly what John did. You could build it Ugly-style, Manhattan-style or, as John chose, Muppet-style. Here is his fully populated board –

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SW40+ (Photo courtesy of N8RVE)

Doesn’t this just look fantastic? This is very inspiring John!

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SW40+ (Photo courtesy of N8RVE)

Then, using the same technique, John built a HiMite 20. The HiMite 15 and 20 were next-generation QRP transceivers based on the Rockmites and, like the SW series of rigs, were the brainchild of Dave Benson. This is John’s version of the HiMite 20. When he first e-mailed me with news of this project, he was having some problems with the receiver. I’m not sure if he was able to solve the issues, but I think it looks great –

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HiMite 20 (Photo courtesy of N8RVE)

Just before¬†his muppet construction odyssey began, John built a WBR, but ended up giving it to a friend who liked it. What to do? Build another one! This one is for the 31M broadcast band. John has had some issues with the volume level though otherwise, it is working OK –

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WBR Receiver (Photo courtesy of N8RVE)

One of the great things about developing the ability to scratch-build (as opposed to assembling projects from kits) is that you can pretty build anything you want, as long as you have the schematic. You can build it using any one of a number of techniques – Ugly Construction, Manhattan, Muppet, or any combination that you wish. You could even design your own PCB and take the drastic measure of drilling holes in it for component leads ūüôā

Thank you for sharing the details of some of your projects with us John, and I hope they inspire some readers the way they did me!

 

August 6, 2014

N8RVE’s WBR Regen Receiver

Filed under: Uncategorized — AA7EE @ 10:54 pm
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I’ve been chatting with John N8RVE via e-mail for a while now. He built a little receiver that I dubbed “The Rugster” – it’s a direct conversion receiver consisting of a standard NE602 front end, with a “poor man’s varactor” (1N4001) to tune the bottom 50KHz of 40M. The AF stages and narrow filtering are provided by the 4SQRP Hi-Per-Mite filter. ¬†John’s Rugster initially drifted a little, then when he used NPO caps in the frequency sensitive ¬†parts of the circuit, the drift issue cleared right up (funny how that happens!) ¬†He was very happy with his Rugster, as am I with mine. ¬†It’s always great to hear of fellow homebuilders successfully completing projects.

More recently, John built a WBR regen receiver with a FAR Circuits board that he picked up at Dayton, and sent along some pictures of the final receiver. Talk about a neat and original enclosure – he used a piece of plexiglass and a reticle from an oscilloscope –

That’s a neatly wound toroid John –

John says that it sounds great, though he uses an outboard amp, as the audio level was low. ¬†I’m thinking it shouldn’t be too hard to construct a one-transistor pre-amp ugly-style, so that this receiver can pack a little more audio output.

Great job John, and thank you for sharing your success with us!

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