TYT TH-9800 – Ultra-Technical Overview

The TYT TH-9800 (and its “Plus” revision) is a quad-band mobile transceiver designed for amateur radio operators who require coverage across HF, VHF, and UHF segments within a single platform. Its architecture supports simultaneous reception on two bands and high-power transmission on four primary amateur bands.

AYBERK BLOG

Ayberk Korkmaz

9/12/20252 min read

TYT TH-9800 – Ultra-Technical Overview

The TYT TH-9800 (and its “Plus” revision) is a quad-band mobile transceiver designed for amateur radio operators who require coverage across HF, VHF, and UHF segments within a single platform. Its architecture supports simultaneous reception on two bands and high-power transmission on four primary amateur bands.

Frequency Coverage

FunctionReceive (RX) RangeTransmit (TX) RangeWideband RX~26–33 MHz, 47–54 MHz, 108–180 MHz, 320–512 MHz, and in some versions 740–950 MHz—Amateur TX Bands—~26–33 MHz, 47–54 MHz, 134–174 MHz, 400–480 MHz

Native ham bands: 29 MHz (10 m), 50 MHz (6 m), 144 MHz (2 m), and 430 MHz (70 cm).

Transmitter Output Power

  • 29/50/144 MHz bands: up to 50 W

  • 430 MHz band: up to 40 W

  • User-selectable low/mid/high settings allow output between 5 W and 50 W (or 40 W on UHF).

Receiver Architecture & Performance

  • Topology: Dual-conversion superheterodyne

  • Intermediate Frequencies: ~49.95 MHz / 450 kHz (left band), 38.85 MHz / 450 kHz (right band)

  • Sensitivity: ≤ 0.2 µV for 12 dB SINAD

  • Squelch threshold: ≤ 0.16 µV

  • Selectivity: ~12 kHz / 30 kHz @ –6 dB / –60 dB

  • Narrow/Wide FM modes supported for adjacent-channel rejection.

Functional Highlights

  • Dual VFO / Dual RX: Independent A/B bands, combinations: V+V, V+U, U+U

  • Full Duplex between VHF and UHF

  • Cross-Band Repeat: Enables use as a field repeater

  • Tone Signalling: CTCSS (≈50 codes), DCS (≈1024), DTMF, 2-tone, 5-tone.

Memory & Stability

  • Memory: ~809 programmable channels

  • Channel step: 2.5 / 5 / 6.25 / 7.5 / 8.33 / 10 / 12.5 / 15 / 25 / 30 / 50 / 100 kHz

  • Frequency stability: ±5 ppm (–10 °C to +60 °C).

Electrical Characteristics

  • Supply voltage: 13.8 V DC (nominal)

  • Current draw: ~0.5 A on standby RX; 8–8.5 A at 50 W TX

  • Operating temperature: –20 °C to +60 °C.

Mechanical Parameters

  • Dimensions: ~140 × 41.5 × 168 mm

  • Weight: ~1.2 kg

  • Antenna impedance: 50 Ω (internal duplexer).

Audio & Modulation

  • AF output: ~2 W @ 8 Ω (≤ 5 % THD)

  • Modulation distortion: < 3 %

  • Spurious/harmonic suppression: typically < –60 dB (–50 dB worst case at 29 MHz).

Lab-Style Measurement Data

ParameterValueNotesSensitivity (12 dB SINAD)≤ 0.2 µVGood weak-signal performanceSquelch opening≤ 0.16 µVSelectivity12 kHz (–6 dB) / 30 kHz (–60 dB)TX distortion< 3 %TX current @ full power~8 A (UHF) / 8.5 A (VHF/HF)Audio response300 Hz–3 kHz flat, roll-off beyond

Expected Frequency Response & Spectral Behavior

  1. Passband shape: Roll-off at the –3 dB points for narrow/wide modes.

  2. Adjacent-channel rejection: ~–60 dB.

  3. AF response: Flat between 300 Hz and 3 kHz.

  4. Harmonics/spurious: 2nd/3rd harmonics below –60 dB under nominal conditions.

Engineering Notes

  • High RF output requires adequate heat dissipation; the transceiver’s chassis doubles as a heat sink.

  • Power cabling should support ≥10 A continuous draw with inline fusing.

  • Antenna system must handle >50 W and maintain <1.5:1 VSWR to protect the PA stage.

  • Performance degrades if supply voltage dips below ~11 V during high-power TX.

Technical Advantages

  • Wide multi-band coverage in a single chassis

  • Excellent flexibility (dual RX, cross-band repeat)

  • Competitive RF power for a compact mobile set

  • Solid audio and modulation fidelity.

Limitations

  • Compliance with local spectrum regulations is essential (10 m and 6 m TX may be restricted).

  • Harmonics increase slightly on 29 MHz at max power.

  • Not intended for continuous duty at full output without adequate ventilation.