> ## Documentation Index
> Fetch the complete documentation index at: https://docs.solidyne.ar/llms.txt
> Use this file to discover all available pages before exploring further.

# Bluetooth Mobile Phones

> Pairing Bluetooth phones to HL2400.

## General Concepts

There are three actions that should not be confused when working with Bluetooth devices:

1. **Enable/Disable Bluetooth on mobile**\
   Refers to turning the Bluetooth function on or off on the phone.\
   This should not be confused with connecting or disconnecting the phone from an already paired device.
2. **Pairing a mobile to a Bluetooth device**\
   The mobile searches and registers a Bluetooth device (example: headphones, hands-free system or HL240-VQ channel). This procedure is performed only once.\
   Once paired, the mobile can connect and disconnect the device from the list of recognized connections.\
   It can also be unpaired, after which the pairing procedure must be repeated.
3. **Connect/Disconnect an already paired device**\
   Refers to establishing or interrupting the connection between the mobile and a device already in the list.\
   This should not be confused with the initial pairing process.

***

## Pairing a mobile with HL240-VQ

The HL240-VQ has two Bluetooth channels identified as **BLT-1** and **BLT-2**.\
The corresponding buttons are illuminated and change their flashing pattern according to the connection status.

### BLT Button Illumination Modes

|  Mode | Status                                  | Description                                                                                                                                                                                                   |
| :---: | --------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **A** | Mobile connected                        | Brief orange light (1s) with long off period (2s). Indicates connection to mobile with no active call.                                                                                                        |
| **B** | Mobile not connected / Call in progress | Slow orange light (2s) with short off period (1s). Indicates call in progress. Returns to mode "A" when call ends. Also indicates Bluetooth on with no mobile connected. Switches to mode "A" when connected. |
| **C** | Search mode (pairing)                   | Fast orange flashing. Allows a phone to find and pair with the HL240-VQ.                                                                                                                                      |
| **D** | Incoming call                           | Solid blue light while ringing.                                                                                                                                                                               |

### Pairing Procedure

<Steps>
  <Step title="Prepare Bluetooth channel">
    Verify that the BLT channel (1 or 2) is off.\
    If it's on, press and hold the button until the LED turns off.
  </Step>

  <Step title="Activate pairing mode on HL240-VQ">
    With Bluetooth off, press and hold the BLT button for \~8 seconds.\
    The LED will first show slow flashing (mode B) then fast flashing (mode C).\
    Release the button: the channel enters search mode.
  </Step>

  <Step title="Search from mobile">
    Enable Bluetooth on the phone and search for new devices.\
    They will appear as **Solidyne BLT-1** or **Solidyne BLT-2**.
  </Step>

  <Step title="Connect">
    Select the corresponding device and confirm pairing.\
    The mobile will be registered in the list of recognized connections.
  </Step>
</Steps>

<Note>
  The device name (Solidyne BLT-1 or BLT-2) can be edited from the phone's Bluetooth settings.\
  A single mobile can be paired to both channels, but can only connect to one at a time.\
  Multiple mobiles can be paired to the same channel, but not connected simultaneously.
</Note>

<Tip>
  Keep the mobile close to the HL240-VQ, avoiding direct contact with the chassis.\
  Maximum recommended distance is 3 meters.
</Tip>

***

## Reconnecting a previously paired mobile

The mobile can disconnect from the HL240-VQ in several situations:

* If Bluetooth is turned off on the phone (the call transfers to mobile).
* If during a call the mobile disconnects from the Bluetooth channel. The call transfers to the phone. If reconnected to Bluetooth, the call returns to HL240-VQ
* If **Speaker** mode is activated on the phone (call transfers to mobile). If "Speaker" mode is cancelled, the call returns to the HL240-VQ channel.
* If Bluetooth is turned off on the HL240-VQ.

In most cases, when Bluetooth is reactivated, reconnection can be automatic.\
If not, it will be necessary to select the Solidyne device again on the mobile.

<Warning>
  Reconnection will not be possible if the HL240-VQ Bluetooth channel was paired to another phone that remains connected.
</Warning>

***

## Volume Adjustment

<Tip>
  On the phone, Bluetooth volume should always be set to maximum to ensure good reception and better signal-to-noise ratio.
</Tip>

* Adjustment must be made during a Bluetooth call.
* If adjusted without an active call, only the mobile's speaker volume changes, not the Bluetooth level.
* The level is stored in each phone. When pairing a new device, adjustment must be repeated.

***

## Turning off Bluetooth on HL240-VQ

To turn off a Bluetooth channel, press and hold the BLT button until it stops flashing.