I've build the original QRP-labs U3S from stock. Means the supplied crystal on the PLL-based synthesiser-board.

This configuration is basically working up to 20m with a lot amount of drift, but you will get many decodes on wsprnet.org. On 6m you can also get spots - once a day :-/

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Kategorie: WSPR

I've finished my second U3s.

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Kategorie: WSPR

Check out my new KiwiSDR running:

 

http://dl2sba.ddns.net:8073

 

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Kategorie: SDR

In this post I describe in details, how you can create the calibration factors for k0 ... k3 based on raw data measured with the power sensor.

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Kategorie: RF Powermeter

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...

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Kategorie: Shack

Test setup

MA1

I made some measurements using my miniVNApro with a simple test fixture fittig the QRP labs lowpass filters.

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Kategorie: WSPR

Measurement of the signal quality of QRP-Labs U3s with low-pass filters.Transmitter output is fed into a homemade 40dB power pad. The spectrum is measured using an SIGLENT SSA3021X analyzer.
The bias voltage was about 2.6VDC and the PA voltage was abt. 7VDC.

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Kategorie: WSPR

My new U3S is online :-)

U3S 2

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Kategorie: WSPR

I've read the PA bias study from Hans and tried to tweak the PA of my U3S for optimum harmonics suppression etc. The spectrum is measured using an SIGLENT SSA3021X analyzer. The power is measured using a 40dB tap and a cheap 20w Dummyload from Diamond: ATT The tap is based on the work of OZ2CPU.

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Kategorie: WSPR

  1. RF Powermeter - Firmware 1.8.1
  2. RF Powermeter - Unstable reading - Reloaded
  3. hamware AT-515 Firmware
  4. hamware AT-615U Firmware
  5. hamware AT-615B Firmware
  6. hamware AT-502/AT-515/AT-615U Interface
  7. hamware AT-502 Firmware - Erweiterung für 160m und 80m
  8. hamware AT-502 Firmware - Update CI-V Schnittstelle
  9. hamware AT-502 Firmware - IRB P02
  10. hamware AT-502 Firmware - K2+RUMLOG
  11. hamware AT-502 Firmware - Kenwood erweitert
  12. GPSDO - Distribution Amplifier
  13. GPSDO - Commandline interface
  14. GPSDO - Some Measurements
  15. GPSDO - GPS Disciplined Oscillator
  16. RF Powermeter - Firmware 1.8.0
  17. RF Powermeter - Firmware 1.7.2
  18. RF Powermeter - Unstable readings
  19. RF Powermeter - Firmware 1.7.1
  20. RF Powermeter - Firmware 1.5.0
  21. RF Powermeter - Adopted Nextion library
  22. RF Powermeter - Precision
  23. SOTA - Flight deck for KX3
  24. SOTA - DM/BW-094 - Kornberg
  25. SOTA - DM/BM-344 - Kleiner Kulm - My first activation is done
  26. SOTA - Working conditions
  27. Switch-mode DC-DC converter
  28. Frog Sounds - Spurious emissions
  29. Frog sounds - The frog has arrived
  30. Frog sounds - How far can you hear a frog croak?

2014 CW (Morse Telegraphy) was added to the German Nationwide Inventory of Intangible Cultural Heritage.

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