Category Archives: Electronics

1×6 switch

Last year I built a 1×6 antenna switch. The switch was designed for my SO2R station. The goal was to built a 2×6 switch (see Top Ten Devices app note) with a high isolation between the different ports.

Previous designs for a 2×6 switch failed due to bad isolation values (less than 50dB). These designs were build with loads of relays, but without a PCB. After some experiments with a A/B switch (with isolation values of around 100dB) the 1×6 switch was designed.

PD9X has some nice images of the switch.

schematic

PCB

BOM

Antenna Splitter

This weekend I built 2 antenne splitters. With the splitter connected to the RX OUT of the K3 I am able to route the antenna signal to both the K3 and the QS1R. The splitter plugs directly into the K3 and only 1 cable is needed to the QS1R.

Design based on W8JI and F6AOJ.

 

 

Skimmer PC

Recently I purchased a QS1R receiver (http://www.srl-llc.com/). I want to run this receiver on a separate computer. Below the suggested specs. The computer will be installed in a 19” box which will not only containt the computer but also the QS1R receiver and the input circuits needed.

MoboCaseCPUPSUSSDMemoryGPU 

TXBPF

This spring I build 2 TXBPF (http://www.5b4agn.net/) filter sets (based on the W3NQN filter designs part 1 and part 2) which were installed in an 19” cabinet.

Beverage switch

For the CQ WW 160m CW contest and the Dutch PACC contest I developed and build (together with PA3FAL) a switchbox which is used to route all beverages to the RX input of the low band stations (40/80/160).

The system is designed to handle 8 receive antennes and route the signals to max 6 radios (2 radios per band). Every station has a remote control box to select one of the RX antennes. Softrock receivers can be stacked onto the mainboard of the PCB which are connected to a Delta 1010LT ADC.

High Power LPFs

Based on the W3NQN designs I build 5 low pass filters. These filters were build to be used with legal limit output power.