TEL - ISDN audio calls from your web browser

Yes. With just your computer and an internet connection for a fixed monthly or annual fee. No ISDN line required.

Tel Tel+
Call landlines
Receive ISDN calls
Outgoing ISDN calls
Call cell phones
Getting started with Tel

Just add Tel to your ipDTL subscription. Older PayPal subscriptions must first be upgraded to our card payment system.

Two service levels are offered: Tel and Tel+. Tel allows calls to landlines and some mobiles in many countries, and the ability to receive incoming ISDN audio calls. Tel+ also allows calls to ISDN audio codecs and a wider range of countries and mobiles.

Making a simple ISDN call

To dial a basic G722 ISDN quickly: Enter the "+" symbol, followed by country code, then the number with any leading zeros omitted.

Click G722 ISDN to dial.

ISDN Number Format Examples:
USA: +1 202 456 1111
UK: +44 20 7766 7300

Advanced ISDN Calls

Most ISDN calls require at least some knowledge about what equipment is at the other end. Before you can receive or make such a call you need to first save an entry in your Destinations list.

Click on the +  icon.

In the first menu selector, choose Dialing Shortcut or to receive an incoming call, Incoming Shortcut.

Now select the correct format for the device to which you wish to connect.

Common ISDN Formats:
US Voice Session:ISDN L2 128 Mono
UK Voice Session:ISDN L2 128 JS
BBC Radio Contribution:ISDN L2 64

In the next box, enter a name that describes the shortcut. e.g. Receive ISDN Call.

For outgoing calls, enter the ISDN number(s) for the destination in the last box(es).

Adjust the other settings as required...

Private:Only your Login IDs can see and call the destination. Deselect to use with Link+. *
Auto RX:This can be useful if you don't know the sending format of the destination.
32/48KHz:There is no standard for this setting. Ask the ISDN owner what it is set to.
56/64kBit:The standard is 64k. In North America, some destinations may require 56k.

Click to save your new destination.

You can now connect by simply clicking it in your main Destinations list. For incoming calls you will then be presented with the number(s) for the ISDN user to dial.

* Note that by default, Link+ is Auto-Accept only. Contact us to change this for use with ISDN.

Advice for the ISDN owner:

Telos Zephyr
Just ask for their settings and match them in ipDTL.

Prodys Pronto
Use the following settings for L2 128: L1>CODEC>MPEG>MODE>TELOS>DUAL

Set to SPEED DIAL 37 for L2 128 or SPEED DIAL 27 for L2 128 JS

Fair Use Policy:

The Tel service is provided on a 'fair-use' basis. Tel+ allows up to five hours of outbound ISDN calls per month. For higher call volumes, please get in touch.