Repeater interface to TYT TH-9000 mobile radio

Radio-side connector

There is a connector on the TH-9000 circuit board with the signals necessary for repeater operation. The pinout is the same as the Jetstream JT-220:

Pin	Function
1	Ground
2	Tx Audio
3	COS (Active Low)
4	Rx Audio
5	PTT (Active Low)
6	5V

(Source: http://www.slvrc.org/220band.htm)

A mating cable harness for the 1.5mm header is made by TE Connectivity (2058943-5, Digikey A100196-ND). The radio normally has no external connector for this header, but there is a DE-sized cutout on the back below the center heat sink protrusion. Because the COS output is active low and the NHRC-2.1 repeater controller requires an active high signal, a conversion circuit is required. The inverted signal can be connected to an unused pin on the DE-9 connector, making the complete external pinout:

Pin	Function
1	Ground
2	Tx Audio
3	COS (Active Low)
4	Rx Audio
5	PTT (Active Low)
6	5V
7	COS (Active High)

NHRC-2.1 connector

Pin	Function
1	Ground
2	CTCSS Decode
3	PTT (Active Low)
4	Tx Audio
5	Rx Audio
6	NC
7	CAS (Active High)
8	Ground
9	Fan

Interface Cable (Simplex)

This interface cable connects the radio to both sides of the controller, allowing simplex repeater mode.

TH-9000	Function	NHRC-2.1
1	Ground	1
2	Tx Audio	4
4	Rx Audio	5
5	PTT	3
7	COS	7

-- StephenCavilia 27 Apr 2014