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The 'Rock-Mite '
A simple CW transceiver for 40 or 20 meters!

see the schematic full size by cklicking the little picture

 The 'Rock-Mite' design grew out of my desire to offer a 'one-evening' CW transceiver kit which would be both affordable and easy to construct. It first appeared at 'Lobstercon' - a QRP gathering on the Maine coast- in early July, 2002, where it was provided to all attendees courtesy of Small Wonder Labs and the NorCal QRP club.


     The Rock-Mite is a crystal-controlled direct-conversion transceiver operating on 7040 KHz / 17060 kHz, the North American 'watering-holes' for QRP activity. (For Europe QRPproject provides  7030 Xtals to meet the European QRP Frequency.  It has an 8-pin PIC microcontroller on-board which controls a T-R offset on key-down. A brief tap of a pushbutton control switch reverses the offset to yield a second operating frequency. Pushing and holding on the pushbutton activates the speed adjustment routine for the built-in Iambic keyer. If you'd rather use an external keyer or straight key, there's a 'drop-through' mode which allows use of an external keying source.

You'll note in the image above that the Rock-Mite uses two crystals. The first is used in the local oscillator for transmitter and receiver. The second is used as a receiver front-end filter. This crystal significantly reduces the 7100-7150 khz SWBC energy present at the receiver mixer; as a result, unwanted SWBC reception is dramatically reduced.

The Rock-mite uses one surface-mount part with fairly large spacing. There are no toroids to wind, so assembly should be a snap! The Rock-Mite uses subminiature epoxy-encapsulated RF chokes instead of toroids- maximum harmonic content is -34 dBc.

SPECIFICATIONS:-

- Double-sided PCB 2.0" x 2.5", plated-thru-holes, solder masked & silkscreened for easy assembly

- 0.5W power output at 12V supply.

- Supply voltage range 8-15V

- Tuning: fix-tuned,  ~7029/7030 Khz (14059/14060)

-automatic T/R offset, reversible

-Built-in Iambic keyer, 5-40 WPM

-Built in sidetone, 700 Hz

- Includes assembly instructions and operating tips

- All on-board parts supplied in kit (as pictured above)

AVAILABILITY:
40m Version:  from Berlin Stock

20m Version:
 we take orders now, kits are on the way from USA

40m European Version, incl 2 7030 kHz Xtals      
20m Version, incl 2 14060 Xtals:                              

Please Note: There's no enclosure kit available for the Rock-Mite. It's 'Altoids-compatible', however, so a source of enclosures is probably as close as your nearest market or pharmacy!
 

 

As an AddOn we offer a Peripheral kit with all parts including a Fishermens or Altoid box.


 BNC 
2x Stereo female for paddle and headphode
Female and male 2,1mm for power
Fishermens or Altoid box (filled, you have to eat by your own :-)
 


 

Link to US RockMite friends, klick the picture

More RockMites, klick the picture

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