From: Steve73@...
To: n0rc@...
Subject: Super Rock Mite pic 1
Date: Monday, February 17, 2003 6:54 PM

Hi Rod,

I am sending several pictures to you for use on your Rock-Mite files.

I made a plexiglass case for it just so I could look at that amazing
little rig.  Iím up to 34 states, and 3 continents with it so far.
The VXO uses a variable capacitor from an old transistor radio.  It
allows me to venture up about 5 khz and down about 5 khz.  Having
blown L1 with early experiments with more power, I now use a higher
capacity choke for L1 for my RM 20, (Mouser 434-23-4R7).  I use a
2N2219 with a heatsink for Q6 now.  I have replaced R18 with a 20 ohm
trimmer pot so I can adjust power from about 500 mw down to just a few
milliwatts.  L1, Q6, Y2, and C8 have machined sleeves for easy
replacement of components.  My RM audio filter is configured so I can
switch between the second stage for maximum filtering or I can bypass
the filtering entirely.  Instead of the 50k volume pot described in
the filter directions, I found a 47k resistor in series with a 5k pot
gave me all the audio control I needed.  There is some howling at the
higher volume levels when using the filter.  The LM386 provides more
than enough audio amplification even when R2 and R3 were replaced with
10k.  I added an audio output on the rear for an external DSP filter
for when QRM is particularly heavy.

I have been dedicated to QRP for a long time, but am now having a ball
with this QRPp Rock Mite.  What a fantastic little rig.


Steve Russell, N7SR