All English articles
Description of wideband amplifier MITEQ AMF-2F-005010-15-10P-L
April 18th 2020
Analysis of an unknown Bias-T for the HF-Bands
April 17th 2024
Controlling the R&S URVD/NRVD Power Meter by LabView
April 16th 2024
Analysis of a 1.3GHz 20W amplifier from China
April 15th 2024
Transmit-Receive-Switch with Attenuator for IF frequencies of 145MHz and 435MHz
April 14th 2024
Analysis of a 2.4GHz 20W amplifier from JDElektronik DJ4ZZ
April 13th 2024
A 4 pole bandpass filter for the 70cm band recycled from a UHF duplexer
April 12th 2024
AMSAT-DL proposal to ESA for a Geostationary Microwave Ham Radio Payload
April 11th 2024
Fullduplex operation in FT8 and FT4 via QO-100
April 10th 2024
Problems with measurement of a 5.7GHz LNA
April 9th 2024
Low cost DIY digital readout for an X-Y-axis table
April 8th 2024
Wideband Amplifier MITEQ AMF-5S-122132-12-13P
April 7th 2024
Wideband Amplifier MITEQ AFS3-02000400-06-10P-4
April 6th 2024
Analysis of an unknown variable attenuator
April 5th 2024
Analysis of a 2.4GHz 1.3W amplifier from Phillip Prinz DL2AM
April 4th 2024
Analysis of a 2.4GHz 900mW amplifier from ID-Elektronik
April 3rd 2024
Building some new Bias-Ts
April 2nd 2024
1.3GHz 2W driver amplifier with M67715
April 1st 2024
Remote VSWR & Power Meter - Presentation at 68th UKW-Tagung Weinheim/Germany 2023
Sept. 9th 2023
Remote VSWR & Power Meter - Paper in the proceedings of the 68th UKW-Tagung Weinheim/Germany 2023
DC overvoltage protection with BTS555
April 26th 2023
How to become QRV on the QO-100 NB transponder - Presentation at meeting of DARC OV A05 in Freiburg/Germany
Mar. 24th 2023
How to become QRV on the QO-100 NB transponder - Presentation at the Dreilaender Sysop Meeting 2023 in Engen/Germany
Feb. 11th 2023
Excellent isolator for the 13cm band of unknown type and brand
Feb. 9th 2023
Retuning Circulator TELEDYNE MICROWAVE C-1S13T-3 to 868MHz
Feb. 5th 2023
Broadband CATV amplifier based on MHW5142A
Feb. 4th 2023
Artificial Mains Network (AMN/LISN) with isolating variable ratio transformer
Jan. 30th 2023
8.4 GHz LHCP Dish Feed
Jan. 27th 2023
ALCATEL FERROCOM 20B1-31 circulator for 1700-2300MHz
Jan. 22nd 2023
Circulator Kathrein France CHF 05080 for the 70cm band
Jan 15th 2023
2.4GHz 200W Circulator based on Skyworks SKYFR-000827
Oct 25th 2022
70cm High Power Circulator by retuning VALVO Band V Circulator
Oct 16th 2022
Connecting the ADALM Pluto SDR to the LAN
Sept. 19th 2022
2400MHz 40W Power Amplifier with MW7IC2400
Sep. 4th 2022
Anritsu Preamplifier MA8610A
Aug 9th 2022
70cm low noise preamplifier P432VDG from Advanced Receiver Research
Wideband Amplifier MITEQ AFS2-04001800-50-8P-2
Aug 8th 2022
Wideband Amplifier MITEQ AMF-5F-06001800-15-10P-E
Unknown 13cm Circulator
Aug 7th 2022
Wideband Amplifier MITEQ AMF-3F-00820096-14-30P
July 28th 2022
ARISS contact with German Astronaut Matthias Maurer Presentation at the Microwave & EME Symposium in Radkow/Poland 2022
June 10th 2022
Ham Radio via QO-100 from DP0GVN in Antarctica Presentation at the Microwave & EME Symposium in Radkow/Poland 2022
HP Server Power Supply HP-HSTNS-PL14 modified for Ham Radio use
June 4th 2022
2-6 GHz Isolator QUEST SM2060T02 characterized at 2.4GHz
June 2nd 2022
Improvement of receiver SNR as a function of its image rejection ratio
Manual for the AMSAT-DL Highspeed Multimedia Modem Software from Kurt DJ0ABR
May 26th 2022
EME UHF-LVR Power and SWR Meter 430-2400MHz
May 24th 2022
A 868MHz bandpass filter K&L Microwave 10B120-865/530-0
May 3rd 2022
A 868MHz bandpass filter for LORAWAN
Mar. 31st 2022
The WellGood active loop antenna tested with the Airspy HF+ SDR
Mar. 6th 2022
Wideband Amplifier MITEQ AMF-3F-005010-10-20P-ITC
Jan 23rd 2022
Unknown 1.9-2.3GHz Isolator
Jan 22nd 2022
A 35MHz-4400MHz RF Signal Generator based on an ADF4351 synthesizer and a PE43702 digital step attenuator
Jan 8th 2022
2400MHz Wilkinson power splitter/combiner
Jan 1st 2022
Comparison table signal generator phase noise
Dec 31st 2021
Table with the most important parameters of various coaxial cables
Isolator 1500-3000 MHz TMT H3930 for the 13cm band
Dec 21st 2021
Isolator AEROTEK E60-1L1FM for the 13cm band
Dec 19th 2021
Circulator SMT 1CY63 SMC1530 for the 13cm band
Nov 24th 2021
S-Band Isolator Western Microwave Model ICS-3113
Oct 14th 2021
HRPT reception using an Airspy R2 and Odroid running Spyserver
July 23rd 2021
20dB Power Attenuator Aeroflex Weinschel Model 6464-1
July 21st 2021
S-band Isolator UTE Microwave Inc. CT-3240 OT
June 14th 2021
S-band Isolator Microwave Associates 7K948
Dualband Feed for EsHail-2
June 3rd 2021
Wideband Amplifier MITEQ AMF-4S-071770-08-13P
May 17th 2021
INMARSAT antenna system analysis and evaluation
What to do if XHRPT is no more running?
May 14th 2021
Characterization of the LNB Bias-T and reference injection board by G0MJW
May 9th 2021
2 Watt Chinese Amplifier module for 40-1200 MHz
May 5th 2021
2.4 GHz 6W PA with 46dB gain for operation via QO-100 especially with SDRs
April 28th 2021
Evaluation of a QFH-antenna-kit for L-Band (1.6 - 1.7 GHz)
Dual dipole linear feed for 1690 MHz to receive EWS-G1
April 25th 2021
1 Watt Chinese Amplifier module for 100-1300 MHz
Wideband Amplifier AVANTEK UT84-1915 10-500 MHz
April 3rd 2021
Wideband Amplifier MITEQ AFS3-05200600-07-10P-4
Vivaldi antenna 1.5 - 15 GHz
Jan. 13th 2021
Isolator ALCATEL FERROCOM 9A82-01 for the 23cm band
Dec. 15th 2020
Dummy load AWI 130.3-0028-008 based on EMC 5659 resistor
Dec. 14th 2020
Filtronic 3800 MHz lowpass filter SL013
Isolator N70522774 from Xiangyu China for the 13cm band
23cm circulator C1214 and isolator I124 from BONN Elektronik
Dec. 10th 2020
The new AMSAT-DL Highspeed Multimedia Modem for the QO-100 narrowband transponder
Dec. 5th 2020
A homebrew desk stand for the ICOM IC-705
Dec. 1st 2020
122 GHz Transverter from VK3CV/WQ1S - improved version from SP team with external reference input - Description
Nov. 29th 2020
122 GHz Transverter from VK3CV/WQ1S - improved version from SP team with external reference input - Schematic
The 2 Element YAGI antenna for 1270 MHz from SG-Labs
Nov. 22nd 2020
LimeSDR mini TX output power at VHF/UHF/SHF bands
Nov. 16th 2020
13cm bandpass filter from SSB-Electronic for QO-100
Nov. 9th 2020
3 pole UHF bandpass filter from R&S retuned to 435 MHz
Nov. 6th 2020
Portable station for QO-100 based on the modules of AMSAT-DL
Sept. 27th 2020
Portable station for QO-100 based on the modules of AMSAT-DL - Presentation at the AMSAT-DL Online Symposium 2020
Sept. 26th 2020
Agenda for the AMSAT-DL Online Symposium 2020
Sept 19th 2020
Surplus filter from NEC retuned from 5731MHz to 5761MHz
Sept. 9th 2020
Low Noise Frontend for 13cm band EME
Aug. 29th 2020
How well works a K&L 1990 MHz lowpass filter in the 13cm band ?
August 20th 2020
A 2m FM receiver for UoSAT designed by G8FXB in 1981
August 19th 2020
A surplus 4 pole S-band filter modified and retuned to 2320 MHz
A 739MHz bandpass filter for the IF of a QO-100 receiver
August 18th 2020
A surplus 4 pole S-band filter modified and retuned to 2400 MHz
August 15th 2020
50 Ohm 1250W dummy load SPINNER BN154796
July 18th 2020
WeatherBox for real-time measurement of atmospheric data and microwave propagation prediction
July 3rd 2020
A 3D printed encasing for the NanoVNA V2
June 24th 2020
Evaluation of low-cost Chinese directional couplers 800-2500MHz for the 23cm and 13cm bands
June 9th 2020
3 GHz O-S-L Cal-Kit with SMA connectors for the Nano-VNA V2
June 7th 2020
50 Ohm 150W dummy load based on Filtronics 921-0028 load assembly
May 23rd 2020
Maximum frequency range of the 50Ohm 50W dummy load RS96610-2 from Radiosystem Sweden
UoSAT-1 bulletins #100 - #109 received by DB2OS
UoSAT-1 bulletins #080 - #100 received by DB2OS
UoSAT-1 bulletins #065 - #079 received by DB2OS
UoSAT-1 bulletins #041 - #064 received by DB2OS
UoSAT-1 bulletins #010 - #040 received by DB2OS
Circulator Philips 2722 162 08591 for the 70cm band
May 17th 2020
Brief comparison of NanoVNA V2 with HP-8753E
April 17th 2020
2.4 GHz 1.3W power amplifier MHL21336
Mar. 21st 2020
2.4 GHz 27W power amplifier with MRF21045
Feb. 23rd 2020
High Power 2320-2400 MHz quadrature hybrid coupler
Feb. 7th 2020
OSL-Cal-Kit from surplus components
Feb. 6th 2020
S-band 90 degree hybrid coupler / branch line coupler
Feb. 5th 2020
Wideband Amplifier MITEQ AMF-3F-01000200-04-13P
Feb. 4th 2020
Diplexer for 23cm and 13cm band
Feb. 3rd 2020
2 GHz 125W dummy load based on EMC 5307ALN resistor
Feb. 2rd 2020
1296 MHz lowpass filter with harmonic notches and integrated reflectometer
Feb. 2nd 2020
Commercial 2300-2400 MHz band-pass filter retuned for QO-100 uplink at 2400-2410 MHz
Jan. 30th 2020
1420 MHz Low Noise Amplifier SLN-1420 from SSB-Electronic
Jan. 29th 2020
Peripheral Mode Isolator WMI PMI-4444-2
Jan. 28th 2020
Characterization of unknown 13cm band isolator
Characterization of unknown S-band isolator 3T-74/097 REV.B
Jan. 27th 2020
Characterization of the Renaissance 3A4NCG circulator in the 13cm band
Jan. 26th 2020
Marconi F1094-11 isolator for 1700-2400MHz
Jan. 25th 2020
2.4 GHz medium power amplifier DG0VE PA13-2-600mW
Jan. 24th 2020
2.3 GHz low noise amplifier KUHNE MKU LNA 231 AH
Jan. 23rd 2020
2.4 GHz power amplifier KUHNE MKU231XL
Jan. 22nd 2020
145 MHz 40W power amplifier based on the Hybrid Module Mitsubishi M57727
Jan. 19th 2020
2.4 GHz 4W power amplifier MHT1008N designed by DJ0ABR and DC1RJJ
Nov. 23rd 2019
LimeSDR mini output power at 2.4 GHz as a function of drive level
Nov. 20th 2019
Unknown isolator for the 70cm band
Nov. 18th 2019
Description of wideband amplifier MITEQ AFS3-00300300-10-10P
120MHz high pass filter K&L 6LH41-120-2000-0-0
Isolator N70522768 from Xiangyu China for the 23cm band
Nov. 17th 2019
4.3-5.0 GHz bandpass filter from surplus BOSCH filter unit
Presentation about QO-100 NB transponder at AMSAT-DL Symposium 2019
Nov. 11th 2019
Description of R&S NG-Z Over Voltage Protection Unit "Überspannungsschutz"
Nov. 4th 2019
Portable setup for QO-100 SSB operations
Oct. 23rd 2019
Transcript of the questions from the students and answers from Luca Parmitano in English including the recorded original sound
Oct. 17th 2019
Video from the ARISS school contact of Luca Parmitano on the ISS with students of GHSE Emmendingen in Europapark Rust
How to to update the firmware of the AOR ARD-300 Multi-Digital Voice Decoder
Oct. 4th 2019
Using a Kathrein 791 145 Dual-Band Combiner as a UHF/SHF Diplexer
Sept. 27th 2019
Optimization and measurement results of the 2m Eggbeater Antenna EGB145RE from ANjO-Antennen
Sept. 5th 2019
Comparison of Dual-Band Feeds POTY and from DJ7GP for QO-100
Aug. 9th 2019
MITEQ FTL-104052 BPF retuned from 2240 MHz to 2350 MHz
Aug. 5th 2019
Homebrew 2.4 GHz 5 pole BPF for QO-10
Aug. 4th 2019
Homebrew 2.4 GHz 4 pole BPF for QO-10
2400 MHz 90 degree hybrid coupler for instance for QO-100
July 27th 2019
10 MHz distribution unit with 4 isolated output ports
July 13th 2019
Case study of a SDR based ground station for Quatar OSCAR-100 - Presentation at Microwave & EME Symposium in Gajow/Poland
June 9th 2018
Description of wideband amplifier MITEQ 121643-15-17
May 22nd 2019
Description of widband amplifier MITEQ 121643-10-17
What's inside the PolyPhaser 101-0103S-A lightning protector
May 15th 2019
KUHNE MKU-342A LNA for the 9cm band
May 1st 2019
L-Band LNA-1535 from WILMANCO
ADALM Pluto TX output power at 2.4 GHz
Apr. 10th 2019
Measurements of TX output power and harmonics of the LimeSDR-USB
How to connect the LimeSDR-USB to the GPIO-Board
Apr. 8th 2019
Bandpassfilter RTX COH2438.75 for 2400 MHz uplink to QO-100
Mar. 31st 2019
TX drift measurements at the ADALM Pluto
Mar. 25th 2019
EsHail-2 / Qatar OSCAR-100 400 Baud PSK beacon - Description of Telemetry Block Format of AO-13 for reference
Mar. 14th 2019
Be careful with cheap 88-108 MHz band reject filters
Jan. 30th 2019
Short S-Band helical omni antenna
Jan. 25th 2019
S-Band Low Noise Amplifier LNA2420
January 24th 2019
10 GHz LNA built from old KU-band LNB
Reception results of the engineering beacon of Eshail-1, EsHail-2 and BADR-7
January 22nd 2019
Description of the R&S SMBV-Z1 reference frequency converter
Analysis of an unknown active biconical S-band antenna
Jan. 21st 2019
What's inside the Kathrein antennas for trains and uses
Jan. 16th 2019
Homebrew DC Dummy Load to test power supplies
Jan. 10th 2019
Analysis of the 12 GHz prescaler teil12-100-1000 from DG0VE
Jan. 7th 2019
Analysis of the 10 MHz Inserter / Extractor from Global Communicatons
Jan. 5th 2019
Frequency Doubler from 3.1-6.4 GHz to 6.2-12.8 GHz based on HMC204MS
Jan. 4th 2019
What's inside the 5.5 GHz high-pass filter HPF5500M
Description of wideband amplifier MITEQ AMF5S-040080-12-13P-V
Dec. 2nd 2018
Transmitting DATV with DATV-Express and the LimeSDR
Nov. 24th 2018
Low Noise Amplifier for 23cm band EME
Nov. 4th 2018
Simple rotator interface based on N1VF adapted to Vicon V380PTX PZT
Nov. 1st 2018
Description of the Isolator Melabs Model H350-153,4T
Sept. 16th 2018
Analysis of a chinese wideband low noise amplifier based on SPF5189Z
Sept. 2nd 2018
Analysis of a chinese broadband Bias-T 10 MHz to 6 GHz
Sept. 1st 2018
Description of wideband amplifier MITEQ AFS3-08500960-15-10P-TC-4
Aug. 27th 2018
Using CHIRP with a RT-Systems USB-Adapter to program the YAESU VX-8R
Aug. 13th 2018
A low cost signal generator for 54 MHz to 13.4 GHz based on ADF5355 - Presentation at Microwave & EME Symposium in Gajow/Poland
3D printing a 1U Cubesat
Jun. 5th 2018
What's inside the PolyPhaser 098-1013G-A lightning protector
June 2nd 2018
Retuning a L-Band branch line coupler
May 10th 2018
Description of the LTE Blocking Filter 67510
April 23rd 2018
April 10th 2018
Improving the ADF5355 synthesizer board (Version with Touch-Display)
Mar. 24th 2018
Dressler ARA-2000 active wideband antenna - what's inside ?
Mar. 13th 2018
Retuning a Microdyne Tubular BPF to 2200-2300 MHz
Feb. 25th 2018
Description of wideband amplifier MITEQ AFS3-04000200-13-LN
Feb. 20th 2018
Analysis of HP 5086-7271 Microwave Power Amplifier
Feb. 6th 2018
10 MHz reference source with automatic switching between OCXO and external reference
Description of Huber + Suhner Lowpass Filter 2500 MHz
Jan. 29th 2018
Description of wideband amplifier MITEQ AMF-5S-107117-12-13P
Jan. 27th 2018
Analysis of the 5.4 GHz Diplex-Filter M00090-01-06 from Elettronica Roma
Jan. 26th 2018
Description of the Fixed Bandpass Filter 612608-001 from Watkins Johnson
Dec. 20th 2017
What's inside of a Dressler ARA-30 active antenna?
Dec. 1st 2017
Description of K&L Bandpass Filter 5B120-2450/180-O/OP
Nov. 24th 2017
Commercial L-Band dielectrical bandpass-filter from Lorch
4. Nov.21st 2017
Description of the MASPRO 2SPN8 Satellite 2-way Splitter
Nov. 1st 2017
What's inside this noname Chinese lightning protector
Oct. 9th 2017
RF-Systems DX-one Active Amplifier rebuilt with New Amplifier by Ulrich HB9AIK
Sept. 25th 2017
Description of wideband amplifier MITEQ IFS4-00101275-45-10P
July 21st 2017
Description of wideband amplifier MITEQ AFS3-00100300-25-23P-6S
Description of wideband amplifier Herotek A1812-119C
Description of wideband amplifier Herotek A152-198
Description of Huber + Suhner Lowpass Filter 2600 MHz
July 18th 2017
Description of K&L Lowpass Filter 13IL10-1920/X2200-N/N
Description of K&L Highpass Filter 11SH10-2400/U13000-N/N
Description of some surplus Power Dividers from Merrimac
July 1st 2017
Modification of the Worldspace Antenna ANA-10L for wideband use
May 1st 2017
Measurement results of a Worldspace 15V low noise amplifier
Measurement results of a Worldspace 2,3V low noise amplifier
Description of the Anritsu MS616B Modulation Analyzer
Instruction Manual FM-AM Signal Generator Boonton Model 102D
A proper metal encasing for the Lime-SDR
April 30th 2017
Service Manual AOR AR-8600 receiver
Radio Amateurs who are also a member of the NexStar Yahoo group
June 23rd 2016
MIRNEWS - Collection of most of the excellent bulletins issued 1991-2001 by Chris van den Berg
April 24th 2016
Description of the wideband amplifier Picosecond 5812
Feb 28th 2016
VHF/UHF satellite frequencies for Frequency Manager in SDR# (based on frequency tables from Maik Hermenau)
Aug. 19th 2015
Description of the tunable bandpass filter Telonics TTA-1500-3-5EE
Jan 10th 2015
Orbitron Note Files
Mar. 15th 2014
Low Noise Amplifier HFC LNA-4000
Oct. 13th 2013
A rubidium frequency standard as a precise reference frequency source for the ham radio station
Sep 29th 2013
Standard AX700E - Scanning Receiver with Panoramic Display - Brochure
March 26th 2013
Extending the frequency range of a Hyperlog 7025 / 7040 logarithmic periodic antenna
April 20th 2012
Low Noise Amplifier LNA-3000 SSB-Electronic
Mar. 11th 2012
Automatic antenna switch for the AOR AR5000 receiver
Jan. 5th 2012
Description of the Accesssory Ports of the AOR AR5000
Jan. 3rd 2012
Simple DOS Software to control the rubidium standard FE5680A
Jan 2nd 2012
Main differences of Radio Direction Finder DDF6001 compared to DDF6000
Dec. 26th 2011
Directional Power Meter RFM 100 from Rohde & Schwarz - English Flyer
Dec. 25h 2011
Radio Direction Finder DDF6000 from Doppler Systems at a first glance
Dec. 9th 2011
Service Manual of the Standard AX-700 receiver / scanner (56 pages, 31 MBytes)
Sept 24th. 2011
What's inside a SSB-Electronic K1701G downconverter (by Marco Bauer)
Aug 6th 2011
Inside the SSB-Electronic ACS-204 antenna switch system
July 2nd 2011
What's inside an X-Phaser
A vintage 2m - 70cm transverter from uk-elektronik (looking for information)
June 24th 2011
How to control (reaction tune) a AOR AR-8600 receiver using a ACECO FC-3002 frequency finder
June 2nd 2011
Table of artificial satellites launched in 1992
April 15th 2011
Table of artificial satellites launched in 1993
Nov 13th 2010
Table of artificial satellites launched in 1991
Oct 17th 2010
Table of artificial satellites launched in 1990
Table of artificial satellites launched in 1989
Table of artificial satellites launched in 1988
Table of artificial satellites launched in 1987
Table of artificial satellites launched in 1986
Table of artificial satellites launched in 1985
Table of artificial satellites launched between 1977 and 1984
Table of artificial satellites launched between 1957 and 1976
A comparison of active magnetic loop antennas
May 8th 2010
A strange logarithmic periodic antenna design - a short analysis
April 1st 2010
Analysis of the "Electronic Antenna" - a novel antenna design
April 1st 2008
A surplus 8 GHz down-converter from NERA
Jan 26th 2008
Schematics of the Standard AX-700 receiver / scanner
Jan 13th. 2008
J.I.L. SX-400 Wideband Receiver/Scanner Schematicsl
Dec. 24th 2007
J.I.L. SX-400 Wideband Receiver/Scanner Service Manual
J.I.L. SX-400 Wideband Receiver/Scanner Owners Manual
Homebrew S-Meter for the AOR AR8600
Oct. 6th 2007
A new toy in the Radio Shack: the ICOM PCR-1000 wideband receiver (a review and tips for improvements incl. DRM)
March 03rd 2007
An RF Proof 30 Amps Power Supply
Dec 29th 2006
Short analysis of the Hawkins WiFi Signal Booster
Sept 10th 2005
How to modify the ICOM IC-735 for DRM reception
July 11th 2004
200 mW power amplifier for 2.4 GHz
Dec. 22nd 2002
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