Converted CB transceiver --> 10-METER (28MHz)
This CB-transceiver based on the Cybernet PTBM117AoX is converted to the 10 meter amateurband (28MHz).
De PCB which is used for the frequency generation:
The above PCB replaces the excisting PLL, in this case the PLL08A.
What has been done to this transceiver :
• LED-display is replaced by a 0.96" 128x64 SPI OLED Display. Also the red windows in front of the display is replaced.
• Channel switch is replaced by an up/down encoder with spitch.
• PLL08A is replaced by a PCB with Arduino, DDS and PLL.
• Final PA transistor 2SC1384 is replaced by a RD16HHF1 to increase the power to 3 watt.
• VCO has go an extra varicap to increase the range (1.7MHz) .
• Lamps (of which some where broken) are replaced by LED's also to save power for the transmitter.
Data of the transceiver after conversion.
Transmitter | Measured Value |
Frequency range | 28.000 - 29.700 MHz |
TX power | 3 Watt |
2e harmonic | >65dB |
3e harmonc | >70dB |
4e harmonic | >70dB |
Receiver | Measured Value |
Sensitivity 12dB sinad | 0.18uV |
Sensitivity 20dB sinad | 0.33uV |
Neighbourchannel suppression (10kHz) | 55dB |
RF gain range | 40dB |
Squelch range | 0.125uV tot 7uV |
LO leakage | -to be measured |
Schematic diagram with the changes in red.
More info about the PCB with the Arduino can be found
here .
Some pictures of the transceiver taken during the conversion proces.