RF Powermeter - Precision
As described here, I've build an RF Powermeter.
The basic firmware is now running. So I started analysing the accuracy of the used meter head.
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- Kategorie: RF Powermeter
SOTA - Flight deck for KX3
Inspired by the work of Richard G3CWI from SOTABEAMS and his flight decks for some QRP transceivers, I decided to build a matching one for my ELECRAFT KX3.
Starting point was a clipboard which can be found for some bucks at AMAZON. In the lower section, I can simply secure my log sheets with the strong clip.
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- Kategorie: SOTA
SOTA - DM/BW-094 - Kornberg
My second SOTA activation is done. Monika (DL6SCF) and I made a short hiking trip on the Swabian Alps. On top of the Kornberg we made a stop and started the activation ... unfortunately we have to shut down operation due to a rising thunderstorm.
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- Kategorie: SOTA
SOTA - DM/BM-344 - Kleiner Kulm - My first activation is done
During a business trip, I took the chance to activate a mountain in the Bavarian low mountains - Kleiner Kulm.
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- Kategorie: SOTA
Weiterlesen: SOTA - DM/BM-344 - Kleiner Kulm - My first activation is done
SOTA - Working conditions
My current working conditions for SOTA are:
- ELECRAFT KX3. With its build in antenna tuner it does a quite remarkable job.
- For the power I use a LiFePO4 battery with 12V 6,6Ah with a build in BMS.
- Microphone for the SSB contacts is the stock-mike from ELECRAFT.
- For CW I use the Palm Pico Paddle.
- Antenna is a HYENDFED 3-band antenna.
- Flight-Deck for KX3
- A 10m fibre pole from DX-Wire - MINI
- Some velcro-straps
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- Kategorie: SOTA
Switch-mode DC-DC converter
I've used one of these cheap switch-mode DC-DC converters (available on eBay for a few bucks) for my WSPR U3S transmitter. Checking the transmitted signal reveals strong spurious emissions. Hints from the QRPLabs group leads me to the cause - the DC-DC converter. Replacing it with a linear LM317 one solves the problem.
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- Kategorie: Power supply
Frog Sounds - Spurious emissions
I've checked this extremly simple concept for spurious emissions and whether they're compliant with the current regulations ...
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- Kategorie: QRP
Frog sounds - The frog has arrived
Yesterday I've build the FROG SOUNDS 40m CW QRP transceiver.
I've ordered it as a kit from eBay Seller for about €10,- inclusive shipping to DL. The kit arrived well packed after about 15 days in my postbox.
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- Kategorie: QRP
Frog sounds - How far can you hear a frog croak?
Currently I've done 6 QSOs with the Frog and my dipole antenna.
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- Kategorie: QRP
Weiterlesen: Frog sounds - How far can you hear a frog croak?
Frog Sounds - Enhancements to the Frog
In 2015 I've build the Frog Sounds QRP transceiver.
This little transceiver still needs improvement:
- The output is still only 400mW
- The key-click is horrible - even with the additional audio cw-filter.
- The suppresion of harmonics is very bad. Check below.
If someone has any ideas how to fix this, please Diese E-Mail-Adresse ist vor Spambots geschützt! Zur Anzeige muss JavaScript eingeschaltet sein!.
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- Kategorie: QRP
Miss Mosquita - a new girl in town
Since last weekend a new QRP transceiver joined my shack 
I bought her used from a German HAM via the QRPFORUM community. The transceiver is one of the older projects from the DL-QRP-AG but still a neat little transceiver. It is still offered in kit-form from QRP-Project in Berlin.
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- Kategorie: QRP
WSPR some data
Here some analysis of my recorded spots data with my spot data collector. As of today there are 45.000 spots recorded in my database.
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- Kategorie: WSPR
RF detectors
I've done some measurements on two RF detectors - one on an older diode detector from ELDITEST 
and another one on an AD8307 based one 
from SV1AFN.
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- Kategorie: Measuring Technology
WSPR first data analysis
My WSPR data collector is now running some days and I started with some basic data analysis.
The power on the bands 60m to 20m is about 100mW!
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- Kategorie: WSPR
WSPR data collector
Inspired from some work found on the Internet and the full functionality of my U3S I've build an automatic spot collector. The spot collector pulls every 5 minutes my spots from WSPRnet.org and puts it into a MYSQL database for later analysis. See the schematic for this setup 
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- Kategorie: WSPR
vna/J ist umgezogen
Alle Informationen bezüglich vna/J sind auf eine neue Webseite umgezogen:
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- Kategorie: vna/J
vna/J moved to a new location
All information regardung vna/J is moved to my new site
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- Kategorie: vna/J
Reflash Arduino UNO ATMEGA16U2
In case you've bricked the UNO bootloader or even the USB bootloader in the ATMEGA16U2, this may help ...
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- Kategorie: Arduino
2014 CW (Morse Telegraphy) was added to the German Nationwide Inventory of Intangible Cultural Heritage.
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© 2022 Dietmar Krause, DL2SBA