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Asterisk users - any up to date list of pulse capable ATA's?

Started by mdodds, April 14, 2015, 09:12:55 AM

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Expanding on kb3pxr's list

HT503 (on FXS port)
HT70X (All in this series with updated firmware.
HT80X/81X with firmware (New December 2017) or higher


VDV-21 (hacked Vonage unit, and possibly VDV-22)

The most reliable for properly detecting pulse dialing that I have seen to date is the UTStarcom IAN-02EX . Both Motorola and Grandstream units tested to date have exhibited issues on some phones. In have NEVER had an issue with the UTStarcom IAN-02EX
Phat Phantom's phreaking phone phettish


As of March 6, 2018, all current generation Grandstream devices with FXS ports will support Pulse dialing. The 500 series, current UCM models (DAHDI), and all devices with 8 or more ports support pulse dialing by default and do not require any configuration changes. All devices with 4 or more ports, except the HandyTone 704 support pulse dialing without additional configuration.

For Handytone devices in the 70x and 80x series Pulse dialing and High ring power are disabled (or not present) by default. To obtain this functionality you must upgrade the firmware to a compatible (ideally latest) version and select yes for "Enable High Ring Power" and "Enable Pulse Dial" on the respective interfaces in the configuration. It has also been reported that the HT802 does not disable pulse dialing capabilities during the call therefore having the effect of using a Pulse to Tone converter.

HT814 and HT818 in the Handytone series support pulse dialing by default and is not configurable, as of Firmware version the HT814 also supports high ring power. Scant details are available on firmware for the HT818.

All Grandstream devices with 16 or more ports seem to support both High ring power and pulse dialing without any configuration. Most Grandstream devices with 24 or more ports also support Neon message waiting lamps.

For gateway devices containing 16 or more ports, pulse dial support is usually hard to find documentation on and may be one sentence in the administration guide to the effect that Pulse dialing is supported. In the 16 port and higher range, additional features can be configured. Many devices start supporting additional Visual MWI modes (Neon and Polarity), feature code customization (enable, disable or change code), and even MultiFrequency (as in Blue Box) signaling. of course, these are enterprise grade devices and are priced accordingly.

I also mentioned DAHDI earlier. Many interface cards for Asterisk PBX systems use the DAHDI (Formerly zaptel) drivers and use similar hardware. Pulse dialing, high ring power, and various message waiting schemes can be configured. Neon is a bit tricky though. On DAHDI, you must select the HVAC (or neon alias) mode instead of HVDC. The output from the SLIC is in fact DC. If you read the source code (and the referenced technical document) you will find that the Neon (HVAC) mode turns on the ringing generator at 4 Hz for 1/8th of a second (half a cycle) to flash the neon light. These cards are not cheap, and the functionality of the cheap Chinese versions are unknown (My PBX is a Raspberry Pi 3).

Note about Grandstream's "Enable High Ring Power" setting: Grandstream devices that have, or later receive this setting operate their ringing generators at a reduced voltage presumably to save power. The hardware capability to run at the higher voltage is not removed and is later made available again in software. While this causes ringing difficulty with mechanical bells, this can be overcome on Western Electric C-type (I haven't tested P or M types) by changing the bias spring adjustment to the weak setting, I haven't had my Automatic Electric equipment connected in about a decade so I haven't tested it.