The USBtinyISP – The First Step In Building Etherkit’s New CC-40 40M QRP Transceiver

Jason NT7S is currently busy building the first beta of his new CC-40 40M QRP transceiver that uses the PCB’s he designed. It hasn’t been completely smooth but then, that’s why beta versions are built before kits go out to the general kit-buying public. The beta builders are beginning to congregate on our private beta builders forum on the etherkit site (I’m sure we all feel very special – I know I do) and we’re all ready and raring to go with our beta builds. Among the beta builders are Brian N1FIY and Mike WB8ICN who are more experienced at building NT7S designs than myself, as they have both built the Willamette Transceiver.  Brian’s Willamette is a little more than half complete. Mike’s is finished and is a real beauty! I did build Jason’s VRX-1 Direct Conversion Receiver as offered by 4SQRP, but it was a simple and straightforward project, so I haven’t truly lost my NT7S virginity yet. Good grief, that didn’t sound right.

In case you’re tuning in for the first time. Here’s a link to the page on Jason’s blog in which he describes the features of this upcoming transceiver. Bear in mind that these are preliminary features; things may change a little by the time the CC-40 reaches the production stage, and also bear in mind the fact that the picture in Jason’s post is a prototype; the kit you receive will have a beautifully produced PCB (oh – and the final version employs surface mounted devices for most of the active and passive devices – in other words, nearly all the components are SMT’s.)

I have to take issue with the name of your blog post though Jason – it’s not exactly lifted out of the pages of the first lesson in the class “Effective Marketing 101”!  Contrary to the title of the post, I think a lot of folk are going to care about this transceiver. The microcontroller, which will control muting, frequency readout, keying, battery status, and possibly other functions in the future can be programmed in-circuit.  By the time the kit is available on the etherkit site, I’m sure that the firmware included on the controller will be very capable, but if you ever need to update the firmware, you’ll be able to do so with the aid of a simple device like the USBtinyISP.

For beta builders like myself, it’s pretty important that we are able to update the firmware ourselves, as Jason is still putting the finishing touches to it, and we won’t have anything like a final version of the firmware with our beta kits.  We could mail the transceiver back to him for re-programming, but it’s probably simpler to do it ourselves, which is where the USBtinyISP kit from Adafruit Industries comes in.  It’s an In-System-Programmer (hence the acronym) for AVR microcontrollers, meaing that to flash new firmware onto the chip, you don’t have to take it out of circuit – you can do it while the chip is still installed on the board in-circuit.

This is hardly worth that much of a description as it’s such a simple kit to build, but I like taking pictures of what goes on here and posting them, so here’s the bag the kit comes in:

You’ll notice that as well as being used as an AVR In-System Programmer (our intended use), it can also be used as a SpokePOV Adapter. What the heck is one of those, I wondered? I thought it was some highly technical buzz-word that had passed me by (as in “Hey Bill, you were coming in 599 when you were using the SpokePOV Adapter wired in parallel with the wim-bim-fertang-fertang-bus-stop-ole-biscuit-barrel.”) Turns out that Adafruit sell a kit for a thing called a SpokePOV which is an array of LED’s that you fix to the back wheel of your bicycle.  POV stands for Persistence Of Vision, and the idea is that as your back wheel spins round, the individual LED’s appear as solid blocks of light.  You can use this USBtinyISP kit to program the patterns that appear on your back wheel, if you also have a SpokePOV kit from Adafruit.

If on the other hand, you’re a boring old fart like me, and just want to use the USBtinyISP to flash new firmware onto the AVR microcontroller in your new CC-40 from etherkit (or any other AVR microcontroller for that matter) just make sure to install wire jumpers in place of R4 and R7 per the instructions.

Look what a simple kit this is:

Here’s the completed board:

and fitted inside the case:

Hey, if I can build this, I can build an Elecraft K2 right? (Well, joking aside, I’m sure that there is nothing hard about the K2 other than an awful lot more parts to be stuffed and soldered.)

Now to find me some small tweezers and some .02″ diameter solder for all those SMT devices in the CC-40 and I’ll be all set.

There’s only one other thing for me to do to in order to get ready for this cool new QRP transceiver, and that is to keep plugging away at the CW, but that’s a subject for another post.

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