1.SDR HF  I/Q S/H receivers DR2A+ and DR2A++ has now DR (dynamic range) IMD3 free close to the 100dB with SMD substitute Philips IC 74LVC4066. DR2A+ and DR2A++ are going from 30 kHz to the 52 MHz without input filters!!

2. SDR HF receiver DR2G. DR2G is my first completely SMT SDR receiver. The SDR RX DR2G goes from 30 kHz to the 70(100)MHz without input filters!!!!

3. ADTRX-2 is new version of my low power SDR transceivers ADTRX1 and ADTRX1-1. The new mono-band QRP SDR HF transceiver AVALA-01 is ADTRX-2 transceiver with added QRP power amplifier and built in band oscillator all on one single side PCB board. Transceiver is optimized for unique PC control in all software.

4. Low power SDR HF I/Q S/H (Sample and Hold) transceiver based on use 74HC4053- ADTRX1 goes from 30 kHz-35 MHz with new boards B3 and B4. Transmission is possible at 3 bands harmonically related. The boards have  built in 4 channel crystal oscillator  with QRP 5Wout power amplifier with LP/BP- part3

5. I translate original articles about DC (direct conversion) receivers from Serbian language to the English and I added some photos of realizations.

6. Article with classification all YU1LM/QRP SDR designs

7. This design is good and small active antenna built  by Reolof Bakker PA0RDT & Aldo Moroni. Every my SDR RX can now receive weak signals in HF range without big antennas.

8. New SDR photo gallery + links related to my design

JANUARY 2007 HOMEBREW

1. Low power SDR HF I/Q S/H (Sample and Hold) transceiver based on use 74HC4053 - ADTRX1 from 30 kHz-35 MHz with external LO - control boards B1 and B2- part2

2. SDR HF I/Q S/H receiver DR2-2. The DR2-2 is DR2 modification of HF SDR receiver without any RF parts. DR2-2 has no coils only R,C and  cheap ICs but it is with outstanding performances.

3.SDR HF  I/Q S/H receiver DR2D. The DR2D SDR RX is DR2B, DR3X modification with possibility to work with 2 times higher LO frequency instead usual optimal 4 times higher . This receiver is working to the maximum input frequency of 50 MHz. With common used AD9850 DDS we can receive 30 MHz without problems with DDS REF frequency of 125 MHz.

4.SDR HF  I/Q S/H receiver DR2E. DR2E is DR2 modification with new post detector amplifiers to improve performances of original design.

5. SDR HF receiver DR2A additional measurements - Tasa YU1LM& Norbert DG1KPN

6. Corrections in previously published my SDR designs

7. AF all pass quadrature  networks - old technique effectively revised

8. 3 Band pass filters for 50 MHz ( 6 m ) band

9. Band pass filters for 144 MHz ( 2 m ) band

10. HF/VHF/UHF SDR receivers part1. I describe some theoretical problems in realization and a I describe a couple SDR receivers without image rejection.

11. Universal crystal HF/VHF oscillator with possibility switching 4 crystals. This is attempt to help SDR fans in  LO realization for my SDR projects.

12.  New SDR Photo gallery

 JULY 2006 HOMEBREW

 All 4 new design are based on use 74HC4053 IC as S/H (sample and hold ) element in demodulators , modulator and transceiver.

1. SDR HF I/Q S/H (Sample and Hold) Receiver-DR3X from 30 kHz-35 MHz  for 3 bands harmonically related with 1(one)  oscillator or 1 XTAL 

2.SDR HF I/Q S/H (Sample and Hold)  Receiver - DR2B  from 30 kHz- 35 MHz with external LO (local oscillator)

3.SDR HF I/Q S/H (Sample and Hold) Mono band Receiver - DR2C from 30 kHz- 50 MHz with LO (local oscillator) at receiving  frequency

4. Low power SDR HF I/Q S/H (Sample and Hold) transceiver- ADTRX1 from 30 kHz-35 MHz with external LO- part1

5. New SDR Photo gallery

6. Forum devoted to my SDR design 

http://www.qrpforum.de/thread.php?threadid=987

 1.  BP 160M  Photo and corrected article

 2.  My QRP Contest philosophy and some my results in contests

 MARCH 2006 HOMEBREW

 1.  SDR Photo gallery

 2.  Band pass filters for Top band -160m       

JANUARY 2006 HOMEBREW

 HAM S/H Sample and Hold SDR (Software Defined Radio) Modulator/Transmitter for DSB, SSB, CW, AM, FM, DRM.. On HF (30 kHz to 70 MHz) in Connection With PC Sound Card or Other Audio Source – Make it Simple as Possible with Outstanding performances - part2

FINAL SOLUTION – Optimized HAM S/H Sample and Hold SDR (Software Defined Radio) Receivers, Modulator/Transmitter for  DSB, SSB, CW, AM, FM, DRM…. HF (30 kHz to 70 MHz) in Connection With PC Sound Card - Make it Simple as Possible with Outstanding Performances -part3

DECEMBER 2005 HOMEBREW