Thank you for purchasing Grandstream’s HT503, the affordable, feature rich, Analog Telephone
Adaptor/IAD. The HT503 combines a sleek design with the latest technology to offer more advanced
telephony features and significantly better integrated router performance than its predecessor – the
HT488. It is the second ATA/IAD in the HandyTone 50x series. The HT503 functions as a true 3-in-1
gateway for PSTN network, analog telephone FXS interface and IP network. It enables remote call
origination and termination from/to PSTN and supports the feature of “hop-on/hop-off” calling.
This manual will help you learn how to operate and manage your HT503 Analog Telephone Adaptor/IAD
and make the best use of its many upgraded features including simple and quick installation, 3-way
conferencing, and remote call origination and “hop-on/hop-off” calling using the programmable PSTN
FXO port. This HT503 is very easy to manage and configure, and is specifically designed to be an easy
to use and affordable VoIP solution for both the residential user and the remote user.
This document is subject to changes without notice. The latest electronic version of this user manual can
be downloaded from the following location: http://www.grandstream.com/resources.html
SAFETY COMPLIANCES
The HT503 adaptor complies with FCC/CE and various safety standards. The HT503 power adaptor is
compliant with UL standard. Only use the universal power adapter provided with the HT503 package.
The manufacturer’s warranty does not cover damages to the phone caused by unsupported power
adaptors.
WARRANTY
If you purchased your HT503 from a reseller, please contact them for replacement, repair or refund. If
you purchased the product directly from Grandstream, contact your Grandstream Sales and Service
Representative for a RMA (Return Materials Authorization) number before you return the product.
Grandstream reserves the right to remedy warranty policy without prior notification.
Caution: Changes or modifications to this product not expressly approved by Grandstream, or operation
of this product in any way other than as detailed by this User Manual, could void your manufacturer
warranty.
• This document is contains links to Grandstream GUI Interfaces. Please remember to download these
examples http://www.grandstream.com/user_manuals/GUI/GUI_HT503.rar for your reference.
• This document is subject to change without notice. The latest electronic version of this user manual is
available for download from the following location:
http://www.grandstream.com/user_manuals/HT503_User_Manual.pdf
• Reproduction or transmittal of the entire or any part, in any form or by any means, electronic or print,
for any purpose without the express written permission of Grandstream Networks, Inc. is not
permitted.
Grandstream Networks, Inc. HT503 User Manual Page 4 of 35
Firmware 1.0.0.6 Last Updated: 6/2007