Product Overview
SURECOM SF-103 Handheld Frequency Counter
Introduction
- Compact, pocket-sized frequency counter with advanced features including field strength measurement.
- Measures frequency of continuous carrier signals from two-way radios with signal strength indication.
- Ideal for maintenance personnel and wireless enthusiasts.
- Easy 4-button control and small size for portability.
- Uses TCXO for ±2 to ±4 ppm accuracy (-45°C to 65°C).
- Covers 2m HAM, VHF, UHF, and supports DMR radio signals.
- Battery level shown on GUI.
Features & Specifications
- Frequency ranges: 2 MHz - 200 MHz and 27 MHz - 2800 MHz selectable.
- CTCSS/DCS decoder for 136-174 MHz and 400-520 MHz bands.
- Digital mode for DMR radio frequency counting.
- Frequency response time: 0.2-0.5 s (CTCSS/DCS: 0.5-1 s).
- TFT color LCD: 240 x 320 pixels with adjustable brightness.
- Built-in rechargeable Li-ion battery, ~113 g weight.
- Auto power off (1-9 minutes) with LED charging indicator.
- Micro USB charging port.
How to Use (Key Operations)
- Power On/Off: Hold [Red key] 3 seconds to power on; hold 3 seconds to power off with countdown.
- Charging: Connect micro USB; red LED means charging, green means full.
- Set Frequency Range: Press [F2 Stop], then [F3 →] to select "Range", [F4 Enter] choose 27M-2.8G or ≤200MHz, then [F2 Run].
- Set Time Gate: Press [F2 Stop], [F3 →] select "Gate", [F4 Enter] choose 0.1s / 0.25s / 0.5s / 1.0s, then [F2 Run].
- Set Digit Resolution: Press [F2], [F3 →] "Gate", [F4 Enter] select digits 3–6 based on range, then [F2 Run].
- Switch Digital DMR Mode: Press [F2], [F3 →] "type", [F4] select Analog or Digital (DMR); digital mode shows 3 decimals.
- Adjust Frequency Fine Tune (2-200 MHz): Adjust PCB VR1 variable resistor (factory preset recommended).
- Use [F3 Menu]: Navigate with [F3 -]/[F4 +], edit with [F2], exit with [F1], save with [F4].
CTCSS Frequencies (Hz)
| CTCSS Frequencies (Hz) | |||
|---|---|---|---|
| 50.0 | 97.4 | 151.4 | 192.8 |
| 55.0 | 100.0 | 156.7 | 196.6 |
| 67.0 | 103.5 | 159.8 | 199.5 |
| 69.3 | 107.2 | 162.2 | 203.5 |
| 71.9 | 110.9 | 165.5 | 206.5 |
CDCSS Codes (Analog Mode, N code only)
Standard N-code values listed in full manual.
Specifications
| Frequency Range | 2 MHz - 2800 MHz selectable |
| Frequency Response Time | 0.2–0.5 s (CTCSS/DCS: 0.5–1 s) |
| Display | 240x320 TFT color LCD, adjustable brightness |
| Power | Built-in rechargeable Li-ion battery (~113 g) |
| Controls | 4 buttons for navigation and settings |
| CTCSS/DCS Decoder | 136–174 MHz and 400–520 MHz analog bands |
| Digital Mode | DMR frequency counter with 3-decimal precision |
| Dimensions | 70 × 25 × 90 mm (without antenna/BNC) |
| Weight | 113 g |
| Signal Attenuation | -10 dB switch; auto gain control |
| Max Signal Input | 5 Vp-p; avoid direct antenna output connection |
Package Contents
- 1 × SF-103 frequency counter
- 1 × Dual-band UHF/VHF antenna
- 1 × Belt clip
- 1 × USB charger with cable
- 1 × English manual
