Question
How do I set up my CHS D750 scanner in HID mode on my device (Android, Apple, Windows)?
 

1) Please "Forget this device"/Remove/Unpair the CHS scanner from your bluetooth settings.

2) Do both resets below:

Pairing Reset

Releases the Bluetooth pairing from the last system the CHS was paired to. This allows new pairing to another system.

A. Power on CHS

B. Press and hold down the Trigger button and press the Power button until you hear a series of 3 tones.

Factory Reset

Reverts CHS back to factory default state. You may scan the barcode with the link provided below on page 4 (also available in the quickstart guide) or you may do it manually.

A. Power on CHS

B. Press and hold down the Trigger button and press the Power button once while still holding down the Trigger button.

C. After 15 seconds, the scanner will beep. Release the Trigger button.

D. The next time you power on the scanner, it will take longer than normal. After the scanner finishes powering on, it will have factory default settings.

https://www.socketmobile.com/docs/default-source/series-7/command-barcode-sheet-2d.pdf?sfvrsn=6

3) Turn scanner on and go to Bluetooth settings to pair to your scanner.

Once you have paired, than you should be able to test a basic UPC barcode in Notes to make sure you are able to scan.