Fig. 1. 23 cm transverter block diagram.
The transverter's IF is 144 MHz. RF output is 1296-1298 MHz at 2 W which is raised to 25 W using the PA. Both units have two multi-color LEDs on the front:
- Input power LED
- Output SWR LED
When a LED is green, all is well. Yellow means warning, and red means a dangerous condition. Figure 2 below shows "all well" on the PA module to the right. The transverter LEDs display yellow and green. The reason for yellow is low input power. This is necessary not to overload the PA module.
Fig. 2. LED indications on transverter and PA during transmit.
The IF-transceiver is Yaesu FT-847. It has a STBY port on the rear panel which goes low during TX. The STBY port is connected to the transverter's PTT port via a coax-cable.
Fig. 3. Transverter and PA inside the alu-box.
Figure 3 shows the transverter and the PA mounted inside a Hammond 1550J alu-box. The RF ports on both modules are fitted with SMA-female connectors. The modules are interconnected with short pieces of RG316D cable having SMA-male connectors.
The PA module becomes warm, but not hot during transmit. The PA module contains a pre-amp with 10 dB gain and NF 0.8 dB.
Fig. 4. The transverter is mounted below the 23 cm antenna.
The water-proof alu-box containing the transverter is mounted below the 23 cm antenna (fig. 4). The middle antenna is a 10-element yagi for 70 cm, and the lower antenna is a 6-element yagi for the 2 meter band.
