Monthly Archives: November 2012

Rockmite

I have finally built a Rockmite.  Rockmite’s are popular little QRP transceiver kits that are designed and sold by Dave Benson (K1SWL) of Small Wonder Labs. Because Rockmites are well regarded and have been around for a bit over 10 years there is a small cottage industry that has sprung up around them to provide accessories and mods.  One in particular is a very nice case, the Mity Box that is built by American Morse Equipment.  They also build a matching key, the Porta Paddle.  I obtained both of these items for my Rockmite build.

Mity Box and Porta Paddle

The Rockmite kit includes all the components and the printed circuit board.  You can also purchase the connector kit which includes all the connectors and such that you will need to get your Rockmite up and running.  The Mity Box is designed to accommodate the connector kit that SWL sells.

Parts included in the connector kit

The first step was to sort out all of the parts.  There are 68 components needed to build a Rockmite.  I sorted them out using a block of Styrofoam.  (Obviously don’t put static sensitive components into the Styrofoam. Leave them in the anti-static bag they come in until you need them.)

Rockmite components

The Rockmite comes with a very good set of instructions for the build.  There is one SMD IC in the kit and you start with that.  Once that part is cleanly on the board you can proceed to add the rest of the components.  There are a few suggestions regarding build order as the board is rather small and you’ll want to follow the specified order so that you can get everything on with a minimum of interference.

SMD IC, resistors, chokes, and IC sockets in place

Board complete

Once all of the components are placed it’s time to add the external components from the connector kit.

Ready for testing

The Supplement To Rockmite Instructions document contains very useful information should you need to troubleshoot a build problem.  Thankfully mine worked correctly the first time.

If you wish to have an AF Gain control, and you will, you will need to remove R5 and use the 1Meg pot that is included in the connector kit.  In order to get the control to work correctly (CW increases AF Gain) connect the wiper to the hole previously occupied by the leg of R5 that went to Pin 7 of U2 and the right-side of the pot (as you look at the shaft) to Pin 6 of U2.

AF Gain pot detail

AF Gain connections

Once the board was built and tested the next task was to arrange everything correctly in order to get it all to fit into the Mity Box.  This is no small task.  After fiddling with it a bit I found it easiest to get the connectors for the Power, Antenna, and Key situated (you will have to solder the center conductor of the BNC for the antenna connector once you have the connector inserted in to the Mity Box) first though you will want to have the AF Gain pot inserted but loose else as you can see above you won’t be able to get it in once you get the board in as it is a tight fit with Y2.  It all fits in the case but there isn’t much room to spare.

Audio, Switch, and AF Gain

Power, Antenna, and Key

And the completed package

The completed package

After some testing at my station I took it over to my Uncle’s station to let him operate it.  He made the first contact with it to WB9GAA in Green Bay, WI.  About 500mW and a 599 signal report.

opr1

W9SIZ operating the Rockmite

opr2

W9SIZ at his station with the Rockmite

The Rockmite is a very nice QRP rig.  It’s fun to build and operate.  I’d recommend adding a Rockmite to your station.

Advertisements