1. Úvod
The YOJOCK HT812A Network Cable Tester is a versatile tool designed for testing network (RJ45) and telephone (RJ11) cables. It efficiently identifies wiring issues such as continuity, short circuits, open wires, miswiring, and cable shielding status. This manual provides detailed instructions for the proper use and maintenance of your HT812A cable tester.

Image 1.1: The YOJOCK HT812A Network Cable Tester with included AAA batteries.
2. Obsah balení
Ověřte, zda jsou v balení přítomny všechny položky:
- 1 x YOJOCK HT812A Network Cable Tester (Master Unit and Remote Unit)
- 2 x AAA baterie
- 1 x Uživatelská příručka
3. Vlastnosti produktu
- Multi-Function Cable Testing: Supports RJ45 (CAT5, CAT5e, CAT6, CAT6A, CAT7) and RJ11 telephone cables.
- Comprehensive Fault Detection: Quickly identifies continuity, short circuits, open wires, miswiring, and cable shielding status.
- Fast/Slow Scan Modes: Adjustable scan speeds for precise fault identification.
- LED indikátory: Clear visual feedback on wire order and fault types for both master and remote units.
- Split-Type Design: Detachable master and remote units for testing long cable runs or installed wall ports.
- Kompaktní a odolný: Ergonomic design with sturdy ABS housing for portability and longevity.
- Jednoduchá obsluha: One-button testing for ease of use.
- Shielding Detection: 'G' light indicates shielded (FTP/STP) or unshielded (UTP) cables.
- Safe PoE Testing: Supports testing of telephone lines and PoE cables with typical voltages under 48-72V, up to 60V.

Obrázek 3.1: Konecview of the HT812A's key features, including line continuity, scan modes, shielded cable detection, and portable design.
4. Komponenty přesview
The HT812A cable tester consists of two main parts: the Master Unit and the Remote Unit.
4.1. Master Unit
- Port RJ45: For connecting Ethernet cables.
- Port RJ11: Pro připojení telefonních kabelů.
- LED Indicators (1-8, G): Display the status of each wire and shielding.
- OFF/FAST/SLOW Switch: Controls power and scan speed.
- Přihrádka na baterie: Houses 2 AAA batteries.
4.2. Remote Unit
- Port RJ45: For connecting the other end of an Ethernet cable.
- Port RJ11: For connecting the other end of a telephone cable.
- LED Indicators (1-8, G): Mirror the master unit's display for remote testing.

Image 4.1: The HT812A tester's RJ45 and RJ11 interfaces, illustrating where cables are connected for testing.
5. Nastavení
5.1. Instalace baterie
- Locate the battery compartment on the back of the Master Unit.
- Otevřete kryt přihrádky.
- Vložte dvě (2) baterie typu AAA a dbejte na správnou polaritu (+/-).
- Bezpečně zavřete kryt bateriového prostoru.
5.2. Connecting Cables for Testing
Before testing, ensure the cable is disconnected from all active network devices.
- For standard cable testing, connect one end of the network (RJ45) or telephone (RJ11) cable to the corresponding port on the Master Unit.
- Connect the other end of the cable to the corresponding port on the Remote Unit.
- For testing installed wall ports or long runs, detach the Remote Unit from the Master Unit. Connect one end of the cable to the Master Unit and the other end to the Remote Unit at the distant location.
6. Návod k obsluze
6.1. Basic Cable Testing
- Ensure batteries are installed and cables are connected as described in Section 5.2.
- Slide the power switch on the Master Unit to either the RYCHLE or POMALÝ pozice.
- Observe the LED indicators on both the Master and Remote Units. The lights will sequentially illuminate from 1 to 8, and then 'G' (for ground/shielding).
- Compare the sequence and illumination patterns on both units to identify any wiring faults (refer to Section 7 for interpretation).
- Once testing is complete, slide the switch to the VYPNUTO position to conserve battery life.

Image 6.1: The HT812A tester demonstrating single-button operation and how LED indicators show good versus poor connections.
6.2. Fast/Slow Scan Mode
The OFF/FAST/SLOW switch allows you to adjust the speed at which the LED indicators illuminate:
- RYCHLE: For quick checks and general continuity testing.
- POMALÝ: For more detailed observation of the LED sequence, useful for identifying subtle miswiring or intermittent issues.

Image 6.2: The Fast/Slow test mode switch on the HT812A Master Unit, allowing users to adjust the LED scan speed.
6.3. Split-Type Testing for Long Runs
The detachable design of the HT812A allows for testing cables installed over long distances or through walls:
- Separate the Remote Unit from the Master Unit.
- Connect one end of the cable to the Master Unit.
- Connect the other end of the cable to the Remote Unit at the distant location (e.g., another room, patch panel).
- Proceed with testing as described in Section 6.1.

Image 6.3: The separable design of the HT812A, allowing the Master and Remote units to be used independently for testing cables in different locations.
6.4. Shielded/Unshielded Cable Detection
The 'G' LED indicator on both units provides information about the cable's shielding:
- If the 'G' light illuminates, the cable is likely shielded (STP/FTP) and the shield is properly connected.
- If the 'G' light does not illuminate, the cable is unshielded (UTP) or the shield connection is faulty.

Image 6.4: The HT812A tester in use, demonstrating its ability to check both shielded and unshielded Ethernet cables and visually indicate wire sequence.
6.5. PoE Cable Testing
The HT812A is designed to safely test cables connected to Power over Ethernet (PoE) devices, routers, or PCs, with a withstand voltage of up to 60V. This prevents damage to the tester or connected equipment during testing.

Image 6.5: The HT812A tester safely connected to a PoE-enabled network device, demonstrating its capability to test powered networks without risk.
7. Interpreting Test Results
The LED indicators on both the Master and Remote Units provide visual feedback on the cable's status. Observe the sequence and patterns to diagnose faults.
7.1. Good Connection (Pass)
All LEDs (1-8, G) on both the Master and Remote Units illuminate sequentially and in the same order, indicating a correctly wired and continuous cable.
7.2. Open Circuit (Open Wire)
If an LED on either the Master or Remote Unit fails to light up in sequence, it indicates an open circuit (broken wire) for that specific pin. For example, if Master LED #3 lights but Remote LED #3 does not, pin 3 is open.

Obrázek 7.1: Příkladamples of LED patterns indicating a continuity problem (pin 2 not lighting) and an open circuit (pin 3 not lighting).
7.3. Zkrat
If two or more LEDs illuminate simultaneously or dimly on either unit, it indicates a short circuit between those wires. For example, if Master LEDs #2 and #4 light dimly at the same time, pins 2 and 4 are shorted.
7.4. Miswire (Cross-Over, Split Pair)
If the LEDs on the Master Unit illuminate in a different sequence than the LEDs on the Remote Unit, it indicates a miswiring. This includes cross-over cables (where transmit and receive pairs are swapped) or split pairs (where wires within a pair are incorrectly terminated).

Obrázek 7.2: Příkladamples of LED patterns indicating a short circuit (pins 2 and 4 lighting dimly together) and a miswire (pins 2 and 4 illuminating in the wrong sequence).
8. Údržba
- Čištění: Zařízení otřete měkkým, suchým hadříkem. Nepoužívejte abrazivní čisticí prostředky ani rozpouštědla.
- Skladování: Tester skladujte na chladném a suchém místě mimo dosah přímého slunečního záření a extrémních teplot.
- Výměna baterie: If the LED indicators become dim or the tester does not power on, replace the AAA batteries. Remove batteries if the device will not be used for an extended period.
- Vyhněte se vlhkosti: Do not expose the tester to water or high humidity.
9. Řešení problémů
- Tester se nezapne: Zkontrolujte instalaci baterií a ujistěte se, že jsou nové.
- No LEDs light up during test: Verify that the cable is properly connected to both the Master and Remote Units. Ensure the power switch is in the FAST or SLOW position.
- Inconsistent LED patterns: Re-seat the cable connectors. If the issue persists, the cable may have an intermittent fault or be severely damaged.
- Remote Unit LEDs do not match Master Unit: This indicates a fault in the cable. Refer to Section 7 for specific fault interpretations.
10. Specifikace
| Funkce | Detail |
|---|---|
| Číslo modelu | HT812A |
| Podporované typy kabelů | RJ45 (CAT5, CAT5e, CAT6, CAT6A, CAT7), RJ11 |
| Zdroj napájení | 2 x AAA baterie (součástí balení) |
| Min. Provozní svtage | 48 V (DC) |
| Max. Withstand Voltage | 60 Volts (for PoE testing) |
| Rozměry | 4.61 x 2.76 x 1.26 palce |
| Hmotnost | 3.53 unce |
| Barva | Černý |
11. Záruka a podpora
For warranty information or technical support, please refer to the product packaging or contact YOJOCK customer service through the retailer where the product was purchased. Keep your purchase receipt for warranty claims.



