Here's `simple'

---------

From: Jeffrey Herman (jeffrey@math.hawaii.edu)
Date: Wed Aug 31 1994 - 23:26:21 EDT


You can't get any simplier than this:

*****************************************************************
Subject: PROJECT 1: 40M QRP XMTR

Hi Gang,
   Here is the first of many very SIMPLE QRP transmitters. I make no
claims to their performance! In the next few weeks I'll give you xmtrs
for 80, 40, 20, and 2 meters; most requiring 3 or less transistors.
The circuits come from 2 out-of-print ham projects books (c. 1968) so
I will assume there will be no copyright problems.
   Project 1 is a simple 40 meter xmtr; it should only take 15 minutes
to build it (if you've got the parts). I wasn't able to draw the symbol
for each part on this terminal, so I put the part number in it's
place. Hope you don't mind... Note that the case of Q1 should be
grounded. Here's the text for this project, taken from "101 EASY
HAM RADIO PROJECTS" by Robert M. Brown, k2zsq/w9hbf and Tom Kneital,
k2aes/wb2aai:

   "Want to really shake up your next contact? Just tell him you are
using this one-transistor CW rig! Most Novices and other hams shy
away from these little gems thinking they are hopelessly underpowered.
Not so! More than 50 contacts - all located over 75 miles distant -
have been logged with this rig connected to the backyard longwire!
   "Construction is quite simple and, in fact, there is not much to
say about it. Reason: there isn't very little that can go wrong!
   "L1 should be adjusted for maximum deflection on an FSM as the
key is depressed. Crystal should be a fundamental frequency type
for 40-meter operation."

Parts list:

C1 68 pF capacitor
C2 .015 uF capacitor
C3 10 pF capacitor
L1 25 turns of No. 26 enameled wire wound on a 3/8 in. slug-
     tuned form (National XR-91 or equiv.)
M1 4.5 volt battery
M2 40-meter fundamental freq. crystal
Q1 GE-9 transistor
R1 91K resistor

--------M2--------*----------*-----------*----------C3-----------ANT.
| | | |
| | | |
| C C1 L1
*--------------B Q1 | |
| E | |
| | ----*------------
| | | |
R1 GND | |
| C2 |
| | |
| GND |
| |
-----------------------------*---------_M1+---KEY-------GND

That's it! Note that GND = ground (and note the polarity of M1).
For Q1, I've labelled its leads B = base, C = collector, E = emitter.
* indicates a junction of 3 or more leads.
Remember, no flames if it doesn't work; I'm just the messanger!

Jeff, NH6IL


Search QRP-L Archives

[ QRP-L Archive | ]
[ 1993 | 1994 | 1995 | 1996 | 1997 | 1998 | 1999 | 2000 ]

---------

This archive was generated by hypermail 2b29 on Fri Jun 02 2000 - 11:26:57 EDT

kd4ab@kd4ab.org