Phone remote ringer

[dugimodo]

Dial tone comes from the telephone exchange or a phone system not the phone, it's sent down the line the same as any other audio. You should be able to hear the tones when you dial though.

2 options I can think of.
1. It's an old school analogue ringer and needs the phone system to send it an AC ring current to make it ring
2. It's a digital device and needs the phone system to send it some kind of signal telling it to ring - probably impossible to test for

[B.M.]

Try to figure out why you had the incorrect readings the last time you measured the 2 core line. What has changed since you last measured?

I suggest that a break (loose connection) in the 48volt line or the zero volt common would be why the system is not working correctly.

Are you measuring at the same places you did before or a different place? The 0 volt and 48 volt should be continuous through the installation surely.

Maybe a phone or some other apparatus had a loop which completes a connection has been unplugged during faultfinding attempts or in error.

Do not dismantle "redundant" wiring until you know how the system is supposed to work.

The old Ringing Voltage was 75v BUT it was 16.66hz and a sawtooth waveform as opposed to sinesidual. Quite how modern day Multi Meters handle such a waveform I do not know.

50v DC was the telephone exchange voltage.

[Tbird650]

Thanks team

Found this interesting Analog Telephone adaptor
Adapts analog devices to IP networks.
Looks suspiciously similar to one little box we have... will check it Tuesday. Feeling excited

[paulw]

I wonder if this ATA is propriety to the PBX system or will it work with any VOIP system. When I worked for NEC we used the Cisco ATA boxes as they could be used anywhere. Let us know how you get on with this .

[Tbird650]

Thanks. That's a very interesting point. Each proprietary makers' equipment may well only play nicely with its' own kind.. Logically any ATA should have an IP address so it can talk to the network.

Churning this possibility of the ATA turning out to be identified as such, my thought to diagnose it is to plug the ringer directly into the ATA. This will eliminate the existing 2-core wiring, much of which can't even be seen. If no go, then the ATA itself could be dead else wherever it interfaces into, possibly the switch. Oh and of note is the switch has 2 network cables that aren't flashing the little telltale "data" lights. (Sorry don't know the real term for this).

Additionally I can test and positively identify the 2-core cable. It has 46v so if I unplug, that voltage will drop to zero.

Tuesday, I'll check all this out. Fingers crossed.

[decibel]

The old Ringing Voltage was 75v BUT it was 16.66hz and a sawtooth waveform as opposed to sinesidual. Quite how modern day Multi Meters handle such a waveform I do not know.

Wow!, B.M. you are talking old here. Ringing moved to 25Hz with the introduction of Step-by-Step.

[paulw]

Wow!, B.M. you are talking old here. Ringing moved to 25Hz with the introduction of Step-by-Step.

Well in Step systems installed in the early 1960s. Up till then they were 16Hz ringer @ 90VAC.

[B.M.]

Wow!, B.M. you are talking old here. Ringing moved to 25Hz with the introduction of Step-by-Step.

Yes it’s getting back a bit all right.

I cut my teeth on Rotary, then mixed in pre 2000 and 2000 step-by-step, including DSR’s.

That entertained me for three years before I shuffled off to Carrier & Toll, later to be renamed Transmission, for my next 12 years before resigning from boredom.

Fujitsu carrier systems had arrived and they just worked.

As an aside I remember asking a instructor at a training school what he thought about transistors.

His reply was “They’re just a novelty son, they’ll never be any use commercially”.

Anyway, thanks decibel for advising of the change.

[Tbird650]

Success, it works again.

Found and identified the ATA as Yeastar TA100. Followed its' network cable back to the switch then realized it was one of those without the little telltale lights working. Followed the power wire back to a USB adaptor. Both the USB adaptor and network cable were replaced with 2nd hand ones. The telltale lights started blinking. Dialed our number and BOOM, it worked.

Two weeks ago, I knew almost nothing. I learnt a lot. Each piece of the puzzle got me closer to understanding.

Thanks to all who helped.

[1101]

As an aside I remember asking a instructor at a training school what he thought about transistors.

His reply was “They’re just a novelty son, they’ll never be any use commercially”.

When I was at ATI (Tech Institute) ,the instructors hated Windows3 /WFW3.1 . They wouldnt teach it, wouldnt have it loaded on their systems.
This was in a Electronics & Computing course