Tubixie - QRP - TRX

Das Röhren Hybrid Transceiver Projekt für mehr Selbstbau im Amateurfunk

Tubixie Tube Hybrid QRP CW Transceiver Kit


- S O L D    O U T -

The Tubixie is a Shortwave Tube Hybrid QRP CW Transceiver Kit for

80m (3.579 mhz Crystal included, you can use any other Crystal from 80m without other changes) or

40m (7.023 mhz Crystal included, you can use any other Crystal from 40m without other changes) or

20m (14.060 mhz Crystal included, you can use any other Crystal from 20m without other changes)

The Circuit based on Pixie II TRX - it´s a simple fun CW-Transceiver.



It is a kit for beginners and professionals - it is very easy to set up. No coils need to be wound. Also tuning works not necessary. Construction time for newcomers about one afternoon, professionals about one hour.

Each kit comes with a circuit diagram and a parts list.

Power measurement with the oscilloscope Agilent Technologies InfiniiVision DSO-X 2004A 70Mhz at a 50 Ohm Dummyload

Output Power at 80m with 3,579 MHz Crystal, 16,5V Sp-Sp (Voltage Peak-Peak)

-> 0,681W = 681mW or ~28dBm :


Output Power at 40m with 7,023 MHz Crystal, 14,4V Sp-Sp (Voltage Peak-Peak)

-> 0,518W = 518mW or ~27dBm :


Output Power at 20m with 14,060 MHz Crystal, 14,3V Sp-Sp (Voltage Peak-Peak)

-> 0,511W = 511mW or ~27dBm :



The kit contains all parts for the selected band - PCB, all electronic Components, Tube, Enclosure, Part list and Circuit. You only need Batteries.


Experience report by Colin DD5CF / G1ZOS:

(first buyer of the 80m Tubixie, special thanks for the first Feedback) 

Just finished building the Tubixie 80m QRP TRX by DO6AE Matthias, now waiting for the xtal socket and 12V batteries to arrive then Smoke Test, 73 Colin DD5CF / G1ZOS……….

The Tubixie is working, smoke test results, no smoke, the 12v batteries arrived but I didn't wait for the xtal socket (to change xtals in the 80m band) and used 3x IC chip pin single row sockets with the center pin cut off instead, it puts out about 300mW and I was using a full size G5RV with homebrew T match, the G5RV has been neglected because it is on the roof and I am not able to get to it anymore at 63 so it it saging in places (same as me) , I was heard by DJ9IE at a distance of 105 Kms, I was was also able to hear a nice clean tone of the Tubixie on the Kiwi SDR website in Bochum, there is no sidetone (like the Pixie) the audio is good , you know when the 9v battery is on its last legs as you get a 70's arcade motorbike game noise in the headphones, I added a switch for the 9v battery, if like me you want to leave the batteries in the case you will need it as the orange LED is always on, the case is of very good quality but I find opening it with my arthritic thumbs difficult, your CW key will need to have a stereo plug, mono plugs short circuit the key socket, my first impressions of the kit are positive, the PCB is well made, you will need a soldering iron with a fine tip, it has no silk screen print on the component side which might be a problem for the inexperienced builder, the position of the polarized components are marked with a + and - signs on the solder side, the circuit diagram and building instructions are very good with a resistor color chart and capacitor markings included, I will try the kit again early tomorrow to see if I can get further and look forward to using the Tubixie on portable ops with a 41m doublet antenna hung up in the trees on the river Rhine, I have received no concession from Matthias DO6AE, I am a satisfied customer, Vy 73 Colin DD5CF / G1ZOS……      .....Just reached 535 Km spotted by DL3KR on 80m and G5RV and 300mW with the Tubixie

Just finished putting the Pixie Switch into the Tubixie, I will need to fix it somehow to stop it moving about, Vy 73 Colin DD5CF/G1ZOS


Experience report by Andy KB1OIQ:

(40m Tubixie, special thanks for the Feedback)

Hi Matthias, I enjoyed building the Tubixie QRP transceiver kit for 40m.  It is the only tube transceiver in my shack.  I have several crystals for that band, in addition to the supplied crystal for 7.023 MHz. One should consider the use of a socket for the crystal. Use care when soldering.  I had 3 solder bridges that required extra time to debug and repair, but now my Tubixie is working quite well!

I measured the following:

1.5V - 48mA always

9.0V - 13mA receive, 135mA transmit

48V  - 2mA always

Power output:  300mW - 400 mW depending on frequency and battery voltage. Moving the switch to the right turns off the Tubixie, but it does not turn off the 9V power.  One might wish to add an additional switch. Move the switch to the left for normal operation. Also, note that there is no side tone during transmit.  Listening on another receiver is very helpful.  The plastic enclosure is very good quality, and I especially like the selection of colors.  The LED at the base of the tube was a nice addition.

Thank you, Matthias, for the Tubixie!

73, Andy KB1OIQ