The Radio Zone >Ham Radio Info >40 Meter QRP CW Trnscvr.

Site hosted by Angelfire.com: Build your free website today!

Radio Zone`s Quik Projects

40 Meter QRP CW Trnscvr

Here is a simple 40 meter QRP, CW transmitter. The Radio Zone makes no claims to the performance of the radio! This is a simple 40 meter xmtr; it should only take 15 minutes to build it (if you've got the parts).

Construction is quite simple, and there is not much to say about it. Reason: there isn't very little that can go wrong! Note: 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. slugtuned form (National XR-91 or equiv.)
M1 4.5 volt battery
M2 40-meter fundamental freq. crystal
Q1 GE-9 transistor
R1 91K resistor

Schematic

--------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.