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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.
TransmitterMeasured Value
Frequency range 28.000 - 29.700 MHz
TX power 3 Watt
2e harmonic>65dB
3e harmonc>70dB
4e harmonic>70dB
ReceiverMeasured Value
Sensitivity 12dB sinad0.18uV
Sensitivity 20dB sinad0.33uV
Neighbourchannel suppression (10kHz)55dB
RF gain range40dB
Squelch range0.125uV 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.