Faulty TYT TH9000 Single Band Radios

[VK5MCH]

DO NOT BUY A TYT TH9000 RADIO. THEY ARE FAULTY FROM THE FACTORY.

Product

TYT TH-9000D (single-band mobile transceiver). Two brand-new units from the same supplier.

Defect summary
After every transmission, the receiver remains muted ("sticky squelch") and does not resume normal reception until a much stronger signal appears. Weak and marginal voice signals never unlock the squelch. This occurs with default settings and persists across power cycles and resets. Reproduced on two brand new units.

How to reproduce
1.   Program a local repeater or simplex channel.
2.   Set SQL to 0 so the audio is open and turn up the volume. Disable CTCSS/DCS.
3.   Plug in an antenna or dummy load.
4.   Transmit for 1–2 s, then unkey.
5.   Observe: RX stays muted. Only a strong carrier re-opens it. Weak signals and noise do not.
6.   Get another radio (Quanshang or similar) and set it to the same frequency. Press the PTT on this radio so the TYT receives a strong signal. Release the PTT on this radio. The TYT now unmutes and goes to fully open audio again.
7.   Issue repeats indefinitely.

Why this is a known model defect (independent sources)
•   Detailed technical write-up: SQL=0 is not truly open; CPU continues to gate audio; post-signal spikes re-close squelch. Includes scope traces and an engineering analysis for APRS use. F4FXL
•   Video reference to the same "TH-9000D squelch problem." YouTube
•   Long-running owner reports citing squelch problems on receive with this model family. myGMRS.com Forums
•   User reviews noting "poppy" squelch closure behavior on the TH-9000 series (evidence of faulty squelch handling). eham.net
•   TYT's own manual shows only standard BCLO/SQL features and provides no fix or setting that resolves the post-TX mute condition. FCC Report+1

Evidence from my order
•   Two brand-new radios exhibit the identical defect out of the box.
•   Not an installation issue: stable 13.8 V supply, low-SWR antenna/load, default programming.
•   Not a configuration issue: SQL levels tested from 0 to 9; BCLO off; no signalling; factory reset tried.
•   Not a one-off failure: matches documented behaviour in independent reports above.

Impact
•   Unfit for purpose as a voice radio. The radio is not fit for purpose as it fails to unlock the squelch after releasing the PTT.
•   Misses weak calls after each transmission.
•   Safety and reliability concern for repeater or link service.

Requested remedy
•   Full refund and return of the radio to you.

References (links)

1.   F4FXL engineering analysis: "And so I wanted to use a TYT TH-9000D for APRS ..." (SQL=0 not truly open; CPU keeps closing squelch). F4FXL
2.   F4FXL video: "TYT TH-9000D squelch problem." YouTube
3.   myGMRS forum review thread noting receive squelch issues on TH-9000. myGMRS.com Forums
4.   eHam user reviews mentioning poppy squelch closure on the TH-9000 series. eham.net
5.   TYT TH-9000D manuals (no documented fix beyond basic SQL/BCLO). FCC Report+1

My YouTube video can be found here https://youtu.be/OazN898Ssaw