Quick Summary
The JOYWEE FF688C is a 3.5 inch colour LCD boat fish finder with dual sonar frequencies of 200 KHz and 83 KHz. It is built to show depth, bottom contour, fish icons and fish depth indicators, with auto zoom, manual zoom and a multi-language menu.
The display is a 3.5 inch 18-bit TFT screen with 320 x 240 resolution and sunlight-readable presentation. The unit shows depth from 2 to 240 ft (0.6 to 80 m) in 1/10th precision, with selectable feet or metre readings and audible fish and depth alarms.
Key Details
| Detail | Verified information and buyer relevance |
|---|---|
| Model | FF688C – helps confirm the exact unit variant. |
| Screen | 3.5 inch 18-bit TFT display, 320 x 240 resolution. |
| Sonar frequencies | 200 KHz and 83 KHz dual beam sonar. |
| Depth range | 2 to 240 ft (0.6 to 80 m), so the stated operating depth range is a key check. |
| Readouts | Bottom contour, water temperature, fish icons, fish depth indicator and battery strength indicator. |
| Menu | Multi-language menu with English, Russian, French, Chinese, Japanese, Finnish, Polish, German, Italian, Spanish, Dutch, Korean, Swedish, Greek and Danish. |
| Alarm functions | Audible fish and depth alarms, with depth alarm from 3 to 99 ft. |
| Power | 800 watts maximum output power and 100 watts RMS power. |
What to Compare Before Buying
- Screen size: The display is 3.5 inches, so check that this suits the way you plan to read sonar data on board.
- Depth range: The stated range is 2 to 240 ft (0.6 to 80 m). Compare that with the water depths you expect to fish.
- Frequency choice: This model uses 200 KHz and 83 KHz dual beam sonar, so confirm that this matches the type of scanning you want.
- Language setup: The menu includes multiple languages, which matters if you want the interface in a specific language.
- Controls and alarms: Check whether auto zoom, manual zoom, fish alarm and depth alarm are the functions you want to rely on.
Who This Product May Suit
This fish finder may suit boat anglers who want a colour screen, depth readout, fish icons and dual sonar frequency in one unit. It is also relevant if you want a menu in one of the listed languages or need the option to switch between feet and metres.
Important Limitations
The buttons are not waterproof, so placement and handling on board matter. The unit also uses a stated depth alarm range of 3 to 99 ft, which is narrower than the full depth display range.
Before You Decide
Confirm the FF688C model, the 3.5 inch screen size and the dual-frequency sonar setup before choosing an offer. Check that the depth range, language menu and alarm functions suit your boat fishing setup, and note that the buttons are not waterproof.
