I try to fix a HARDROCK-50 amplifier, which a fellow HAM bought second hand but it didn't really work.

2-tone generator - FA-2-NF etc.

One of my HAM fellows has build a new 2kW HF amplifier. Together with his SDR ANAN-100 he gets really impressive IM3 values.

This inspires me also to do some measurements on my existing HF transceivers - K3 & KX3. For this I needed a two-tone generator.

Cheat sheet for HamGadgets Ultra Picokeyer

I've made a simple cheat sheet for my HamGadgets Ultra Picokeyer because it is hard to remember the various key sequences and abbreviations in the menu mode :-)

100W Dummyload (Funkamateur)

Die Zeitschrift Funkamateuer bietet einen Bausatz für ein Leistungsdämpfungsglied an.


Last week I received my long awaited K-POD from QRP-Project in Berlin.


Detailed measurement on audio CW-filter

Here I've build an audio CW-filter based on the circuit from NM0S/4SQRP.

This filter works pretty well. I've done some audio analysis using a cheap soundcard from BEHRINGER and the shareware application AUDIOTESTER.

Audio CW-Filter finished

Now I've finished the Audio CW-filter I've decribed here in details.

Audio CW-Filter NM0S/4SQRP

Last year I've build the cheap Frog Sounds QRP Transceiver. This transceiver has a pretty basic audio section - a simple LM386 audio amplifier with some LC/RC filtering.

Rotator control and the NodeMCU - a proof of concept


Inspired from the work of EA4TX and K3NG I decided to check, whether the ESP8266 based NodeMCU 1.0 (ESP-12E) is usable as a simple remote IP-based rotator control. You can get the NodeMCU in a decent quality on eBay.

Idea was, to link a local emulated serial port to the NodeMCU module. The HAM Radio applications are communicating via the standard Yaesu GS232A protocol with the emulated serial port.  This emulated serial port then forwards the serial requests to the NodeMCU.

CW-Sensor-Keyer reloaded

You may have seen my build version of the M0UKD sensor keyer and the Bamatech sensor head

As you can see in this post, I've used a simple slide switch to control the power for the sensor keyer. This was a little bit annoying, as you must always check, whether you've turned of the power, when you leave the shack.

As power consumption is not really a big issue - the keyer draws about 2.5mA from two AA-cells. Based on the capacity of an average Energizer Classic AA battery of 1.200mA you will get an on-time of about 300h.

Since many months I've had the idea, to add an electronic switch to the keyer, so it switch of automatically after 15 minutes of idle time.


Based on the work of John, M0UKD, I've build a small sensor-keyer. I used a surplus aluminium shelf and two aluminium stand-offs as "paddles".

See the evolution of this project here.

nanoKeyer - neue Frontplatte

Für den ersten nanoKeyer habe ich mir zwar das Original-Gehäuse gekauft, aber der Einfachheit halber eine simple Alu-Fronplatte genommen. So richtig schick war die auf Dauer nicht. Es wurde langsam Zeit, dass er noch eine schöne Frontplatte bekommt.

XPhase - Interference reduction

Some weeks ago I've build a full-featured XPhase for my father, DK1UO. He is sometimes affected by heavy interference from Plasma-TVs or similar scrap

The function of the XPhase is based on the fact that the interfering signal, received by an auxiliary antenna, is added phase-shifted to the signal received from the main antenna. When the phase-shift is more or less 180°, the interfering signal is canceled out.

My XPhase is based on the work of Hanns, DK9NL. A commercial versions can be found here under the name QRM-Eliminator. Google will provide you some futher informations.

Splitter/Combiner - Funkamateur.de

Heute ist mein Bausatz vom Funkamateur für den Splitter/Combiner für den Frequenzbereich von 0,1-450MHz geliefert worden. Nun Bausatz ist ja schon fast übertrieben - vier Bauteile sind einzulöten; 1xCombinermodul + 3xBNC Buchsen.

Powermeter von DG7XO

Ich habe das Leistungsmessmodul von Oliver, DG7XO nachgebaut. Es wurde in zwei Versionen in der cqDL vorgestellt. Oliver hat mir freundlicherweise eine Platine geätzt und den AVR programmiert, so dass nur noch Löten und Mechanik angesagt war...

nanoKeyer - Extensions - 2nd

Saving parameter to EEPROM

I've discovered, that the value of the weighting feature is not saved to the EEPROM. I'Ve updated the Sketch.

All my changes in the sketch are surrounded with a conditional statement:

#ifdef DL2SBA...#endif

and should be discovered easily.

nanoKeyer -Extensions


I've applied the following extension to my nanoKeyer:

  • Powersupply
  • Memory bank selection
  • smaller code changes


Mini Morsetaste SQUEEKY

Neu im Stall ist die kleine Morsetaste SQUEEKY von DK1WE 


Aus Zeitmangel zu verkaufen - Bei Interesse bitte Diese E-Mail-Adresse ist vor Spambots geschützt! Zur Anzeige muss JavaScript eingeschaltet sein!.

Nachdem ich mit Olivers Powermeter meine ersten Schritte in Richtung Shack-Automation unternommen habe, habe ich ein bischen weitergebaut …

Ich habe nun neben dem Powermeter auch noch ein WAVENODE SWR-Meter sowie meine beiden DIERKING Antennenumschalter integriert.