The next generation CAR UNIT replacement for the Kenwood TS850 transceiver
This board is a aftermarked replacement for the Kenwood CAR UNIT (X50-3140-00) with four YM6631 and/or YM66312 DDS chips, which is no longer available as original spare part.
The CAR UNIT do many different things in the TS850: from generating 4 different RF signals used as LO signals in the mixers – to even generating the side tone when sending CW or CTCSS sub tones in FM split mode.
TS850 "NG CARRIER UNIT" Project webpage
To replace the original CAR UNIT, the new board was developed based on a high performance FPGA chip (Field Programmable Gate Array), which include the function of all 4 ASIC’s YM6631/YM66312 and some peripheral circuits in only one chip !!
Due the high performance of the FPGA the functions of the peripheral circuits (mixers, ceramic filters etc.) could be minimized to achieve a higher design flexibility of this board. Furthermore, a high spectral purity of generated RF signals and matched output levels are the results of an accurate signal routing, PCB design and analog circuits.
All screw mounting holes are in the same location and all connector labels have the same description on the printed circuit board as on the original unit, which permit a easy “plug and play” replacement of a defectiv CAR UNIT. Furthermore there are no alignments necessary on the transceiver after the replacement of this board.