Ringer impedance and Grandstream HT503 ATA

[markosjal]

I am not looking for a definition of an ATAs handicap at making bells ring , however I am interested in info on WE and AE ringer impedance and capacitor  values , as well as any similar experinces

I have here a Grandstream Handytone 503 with one FXS and one FXO port.

When I connect say a stock AE Styleline phone to it , the ringer does not ring . I can sometimes get a rattle or vibration . Same result with WE Princess 2702BM but seems to excite ringer on Princess better than styleline.

Now I have here Mexican Indetel, and Mexican Ericsson phones which seem to use interchangeable ringer coils, clappers and gongs. These all ring without issue on the HT503



Do AT and WE sets all use a total of 1Kohm ringer coils with .47 mF capacitors?

The Mexican Indetels and Erricssons seem to use different values. Dead DC resistance across one ringer was 1.7Kohm with .33mF capacitor


Can anyone enlighten me also as to what AE would call "High Z" . I am pretty sure this refers to ringer impedance more than anything. As I have now seen several Multi Line sets that were sold for use in Mexico with a "High Z" or "High Impedance" stamp on bottom.

Thanks

Mark

[TelePlay]

What does FXS and FXO mean?

They are not in our acronym list and I will put them there if you can define them.

[markosjal]

Best definition I could find on the web

http://www.differencebetween.net/technology/difference-between-fxo-and-fxs/

[dsk]

To make it simple: The FXS is where you plug in the phone. The FXO is to the telephone line from the telco.
With both FXS and FXO you may use a telephone for receiving both POTS and VOIP calls, and you may call out on the same 2 channels, internet and POTS.   Depending on ATA this outgoing routing may be more or less automatic, depending on what you dial.  This programming may sometimes be complex, but usually not.

dsk

[kb3pxr]

Go to the FXS settings tab and select Yes on "Enable High Ring Power." Probably want to do the same for "Enable Pulse Dial" while you are there.

As for FXS/FXO, it's easy. The FX stands for Foreign Exchange, that isn't as important as the last letter. S stands for station and O stands for office. This means the FXS port is to connect to station equipment, and the FXO is to connect to (Central) office equipment.

Edit to Add: If those settings aren't there, upgrade the firmware. Grandstream usually adds these features in later updates. As of this month even the latest HT80x series has these options enabled in a firmware update.

[markosjal]

Neither setting you mention exists in current HT503 Firmware .

I saw another post where you mentioned the same and I have never seen any such settings in any Grandstream Firmware

[kb3pxr]

Neither setting you mention exists in current HT503 Firmware .

I saw another post where you mentioned the same and I have never seen any such settings in any Grandstream Firmware

I apologize, that setting does not apply to the 50X series. It appears that the 50x series does not have the settings. However in the 70x series and the 80x series, a firmware update enable these settings, per Grandstream documentation.

[kb3pxr]

I've since acquired two HandyTone 502s and have done some testing. Unless you have faulty capacitors or the output of the 503 is lower, I can rule out any electrical issues. I have a WE Trimline and the only major difference is the Trimline uses the P-Type and the Princess uses the M-Type. These ringers vary mechanically, but the impedence is identical. Additionally, my Trimline has a .46µF capacitor instead of your .47µF which electrically is not really worth mentioning.

Since we both have a mutual interest in ringer compatibility, I will likely be performing more research on this issue. If you would like to try to duplicate my results for a WE Trimline, the Bias Spring needs to be in the strong position in order for the volume control to have effect, otherwise it will ring loud.

[Owain]

In the UK ringers are either 2 x 500 ohm (1 kohm) with multiple phones in series, or 2 x 2 kohm (4 kohm total) with multiple phones in parallel.

If the ATA won't ring <2kohm bells, try an AC voltmeter across the bells and see if the bells are dragging the ATA output low. If they are, try a resistor of about 1k - 3k in series with the bells, which might be enough to give you enough voltage to get a tinkle.

[markosjal]

In the UK ringers are either 2 x 500 ohm (1 kohm) with multiple phones in series, or 2 x 2 kohm (4 kohm total) with multiple phones in parallel.

If the ATA won't ring <2kohm bells, try an AC voltmeter across the bells and see if the bells are dragging the ATA output low. If they are, try a resistor of about 1k - 3k in series with the bells, which might be enough to give you enough voltage to get a tinkle.

I have seen this on some Ericssons in Mexico and I had thought about testing it but never have

Good idea to try

Mark

[dsk]

Sitting in the bus, writing: Ringer impedance dependens of coils and of capacitors. I have measured ren-loads from 5 to less than 0.5. More than 2 use to make trouble for Sipuri ATA's.


dsk