The QYT KT8900 radio with an Allstarlink node

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Good news: The QYT KT-8900 and KT-8900D radios are well suited for running an Allstalink node. The configuration menu REP-M (#43 on KT-8900, #51 on KT-8900D) allows two radios to make a repeater by connecting a cable between the two microphone connectors (RJ45 plugs). The configuration feeds a RPT-CTLR signal when the squelch opens (or subtone received) through the mic connector which is wired to the PTT on the other radio.

The RPT-CTLR is effectively a COR signal which can be wired to the DMK URI for Allstarlink operation, and no modification to the radio circuit board is necessary. As a proof of concept, I sacrificed an ethernet cable and soldered a DB25 plug on it according to the wiring shown on the picture. This works as expected and with good sound quality. The KT-8900D offers much radio for the money, and I believe it should be interesting for use in private Allstarlink nodes.
The RPT-CTLR is active low, so you need to set “carrierfrom=usbinvert” in simpleusb.conf

After 3 hours operation on 95% duty cycle, the radio is only lukewarm, using low output power (10w)

The Allstalink node connected to the Mic connector of KT8900D

The wiring arrangement for the DB25 and the DMK URI board

One thought on “The QYT KT8900 radio with an Allstarlink node

  1. Pingback: QYT KT-8900D: Best Budget Mobile Radio – Ham Radio Insights

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