JH-A420 OTC Hearing Aid User Manual

Document Version: V1-1
Model: JH-A420 (Over-the-Counter Hearing Aid, In-Ear)
Manufacturer: Huizhou Jinghao Medical Technology Co., Ltd. (JINGHAO)

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Product Overview #

This user manual provides comprehensive instructions for the JH-A420 Over-the-Counter (OTC) Hearing Aid. Equipped with an innovative In-Ear Detection Sensor, these hearing aids automatically turn on when inserted and enter standby mode when removed. Please read this manual thoroughly before use. This device is intended for users aged 18 or older with mild to moderate hearing loss.

Table of Contents #

1. Important Safety Warnings (FDA OTC Compliance)
2. Contraindications & Cautions
3. Getting to Know Your Device & Accessories
4. Using the Hearing Aids (Fitting, Smart On/Off, Volume, Programs)
5. Using the Charging Case & Battery Status
6. Maintenance & Cleaning
7. Troubleshooting Guide
8. Technical Specifications & Regulatory Information

1. Important Safety Warnings (FDA OTC Compliance) #

• Age Restriction: If you are younger than 18, DO NOT use this device. You should go to a doctor, preferably an ENT, because your condition needs specialized care. OTC hearing aids are only for users who are age 18 or older.
• When to See a Doctor: If you have any of the following problems, please see a doctor (preferably an ENT):
  • Your ear has a birth defect, unusual shape, or was injured/deformed in an accident.
  • You saw blood, pus, or fluid coming out of your ear in the past 6 months.
  • Your ear feels painful or uncomfortable, or you have a lot of earwax.
  • You get really dizzy, have vertigo, or hear ringing/buzzing in only one ear.
  • Your hearing changed suddenly in the past 6 months, or it gets worse then gets better again.
• Pain Warning: This hearing aid should not cause pain when inserting it. Remove the device if it causes pain or discomfort.
• FDA Reporting: To report a problem involving your hearing aid, submit information to the FDA as soon as possible via https://www.fda.gov/Safety/MedWatch or call 1-800-FDA-1088.

2. Contraindications #

Do NOT use this device if you have:

• Congenital atresia of the external ear or deformity of any part of the ear canal.
• Unstable deafness, or fluctuating hearing loss.
• Persistent headaches, dizziness, earaches, or tinnitus.
• Sudden onset of hearing loss within the past 3 months, rapid progressive deafness, or unilateral hearing loss.
• Effusion (secretions/discharge) in the ear or frequent purulence (pus).
• Acute otitis externa, tympanitis, or acute/chronic suppurative otitis media.
• Allergic reactions to the materials of this product.

3. Getting to Know Your Device #

• Hearing Aid: Features microphones, a multi-function button (program/volume/on-off), soft silicone eartip, In-Ear Detection Sensor, speaker unit, and charging contacts.
• Charging Case: Features charging slots, L/R and case indicator lights, power switch button (to check battery status), and a USB charging port.
• Markings: “L” is for Left, “R” is for Right.

4. Using the Hearing Aids #

• Fitting Eartips: Choose the suitable size (L/M/S) and push firmly onto the speaker unit.
• Smart ON/OFF (In-Ear Detection):
  • Turn ON: Insert the hearing aids into your ears. They will automatically turn on in about 10 seconds.
  • Standby/Turn OFF: Remove them from your ears to enter standby mode. Place them back in the charging case to turn off and charge.
  • Manual Control: Press and hold the multi-function button for 2 seconds to turn on/off.
• Volume Control: 5 volume levels. Press the “+” button for 1 second to increase, and the “-” button for 1 second to decrease.
• Program Switch: 2 preset programs (Program 1 & Program 2). Press the “+” button for 2 seconds to switch. (Beep tones indicate different programs).

5. Using the Charging Case #

• Charging the Hearing Aids: Place them in the correct slots. Blue lights indicate charging; White lights indicate fully charged.
• Battery Status Check: Short press the button on the charging case once. The 4 blue LED lights will indicate the remaining battery capacity (100%, 75%~100%, 50%~75%, 25%~50%, 0%~25%).
• Charging the Case: Connect the USB cable to the charging port. The case can charge the hearing aids whether the upper cover is open or closed.

6. Maintenance & Cleaning #

• Do not drop the hearing aids or expose them to high temperatures, humidity, or liquids (do not swim or shower with them).
• Do not use sharp tools to dislodge earwax.
• Clean eartips daily with the provided cleaning tool. Do not use water, solvents, or cleaning fluids.
• Replace eartips every 3-6 months or when they become stiff, brittle, or discolored.

7. Troubleshooting Guide #

• Feedback/Whistling: Check if the eartip is broken or clogged. Ensure correct insertion. Try a larger eartip or remove earwax.
• No Sound/Voice is Weak: Check if the battery is charged, volume is high enough, or if the microphone is clogged.
• Charging Case Issue: Ensure the adapter is powered, the USB cable is connected correctly, and the charging contacts are clean.

8. Technical Specifications (Program 1) #

• Test Standard: ANSI S3.22-2014
• Max Output (OSPL90): 109dB
• HFA FOG@50: 26dB
• Total Harmonic Distortion (THD): 2%
• Equivalent Input Noise (EIN): 22dB
• Latency: 14ms
• Frequency Response Bandwidth: F1=200Hz, F2=5800Hz
• Battery Life: ≥16 hours
• Operating Environment: 0°C~40°C, 30%-75%RH

Regulatory Information & Manufacturer #

Manufacturer: Huizhou Jinghao Medical Technology Co., Ltd.
Address: No. 207, South SiHuan Rd, ZhongKai Hi-tech District, Huizhou, Guangdong, China. Zip Code: 516000
Website: www.jhhearingaids.com | Email: emily@jhhearingaids.com
Warranty: This limited warranty covers defects in material and workmanship for one (1) year from the date of delivery.