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Old 18th Nov 2021, 10:01 pm   #1
newbieuser95
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Default (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

Hi all, I bought this phone from ebay. It was working fine when I bought it and cleaned it up, worked fine. I moved houses and when I connected it back up, the bell stopped working. It's connected and when I call someone it goes through but when there is an incomming call no bell ringing. It has 2K resistor connected to the bell.

What can I do to fix it? Do I need to replace a part ?

Any advice is welcomed.

Thanks.
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Old 19th Nov 2021, 6:22 am   #2
dagskarlsen
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

It is so many standards out there, so e.g. if you had the UK standard with a third wire for the ringer, and you do not have that now you may need to put in a capacitor.

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Old 19th Nov 2021, 10:06 pm   #3
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

I doubt very much there is anything wrong with the phone itself, it will more likely be an issue with the extension wiring in your new house, specifically the connection to pin 3 of the socket, as modern phones work fine without it.

Try plugging the phone into the larger master socket where the line enters the property.

The easiest way to make it ring in this circumstance is to plug the phone in via a spare broadband microfilter, as this will have a capacitor which recreates the missing ringing signal on pin 3.
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Old 19th Nov 2021, 10:38 pm   #4
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

From >30 years memory the master socket should have 1.8uF capacitor from pin 1 to pin 3. Ringing voltage would be about 15Hz, 75v RMS AC on the incoming line.
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Old 19th Nov 2021, 11:06 pm   #5
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

Hi guys,

Thanks for the reply. Unfortunately I don't have a by master socket. I am with virgin and they don't require a telephone line. I had the phone plugged into the router directly via an adapter.
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Old 20th Nov 2021, 7:05 am   #6
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

Did you have the same setup before? Or is this a new setup with that router?
If "No", the adapter does not solve that need as the master socket did, and you will need a capacitor, or a master socket connected to the router. If Yes, it will be more difficult to find the answer.
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Old 20th Nov 2021, 7:43 am   #7
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

As stated earlier, the simplest solution is to interpose a spare ADSL filter, as UK ones include a ringing capacitor. If you don't have one (given the setup you describe), they are available online for about 1.50 upwards (which is probably cheaper than someone can post a spare one to you).
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Old 20th Nov 2021, 10:28 am   #8
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

Yes, @dagskarlsen it is the same setup.

Okay, @Dave Moll I will buy a ADSL filter and see if it solves the issue.

Thanks guys for the help, will update soon.
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Old 20th Nov 2021, 8:31 pm   #9
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

Unfortunately, the little adapter cable that VM supply with their router does not have the required capacitor.

This one should have:

https://www.toolstation.com/line-ada...E&gclsrc=aw.ds

But if you have a spare ADSL filter from a previous installation handy, plugging it in between the line adapter and the phone will have the same effect.

Quote:
Originally Posted by newbieuser95 View Post
Yes, @dagskarlsen it is the same setup.

.
That's odd, are you saying you moved the VM router and adapter cable from the old house (where the 746 phone rang) to the new house (where it doesn't)?
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Old 21st Nov 2021, 7:44 am   #10
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

I was able to dig out the F version of the diagram, it should be equal.
I have marked straps with red for use without master socket/adapter with capacitor. I guess it will work nice without the blue strap (try it out after the ringing is back) The other straps (black) should be left as they are, they are not important in hence of ringing, an the rest is working so do not move them. The 3.3 k ohms resistor is one we do not agree about the need, I would usually had a strap there too, and that may be worth to test out if the red straps do not solve the ringer problem. The resistor is there to reduce the load of the ringer to allow more telephones at the line at the same time. If you have a resistor there today, do not change it just because of the value, (someone has put it in to do that job described for the 3k3 resistor) but you may test to strap it.
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Old 21st Nov 2021, 9:09 am   #11
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

The blue strap should have no effect in the "on hook" condition. To be honest, I have never found a good explanation for its existence, as it simply bypasses the gravity switch that disconnects the bell when off hook.
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Old 22nd Nov 2021, 8:03 am   #12
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

Quote:
Originally Posted by Dave Moll View Post
The blue strap should have no effect in the "on hook" condition. To be honest, I have never found a good explanation for its existence, as it simply bypasses the gravity switch that disconnects the bell when off hook.
As we know theory ant practices are just equal by theory

The reason for that switch is to reduce loss of signal trough ringer circuit, and tinkling when dialing.

If this not is a problem the blue strap could just be there.
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Old 22nd Nov 2021, 8:07 am   #13
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

Quote:
Originally Posted by newbieuser95 View Post
...I will buy a ADSL filter...
Before you spend your hard-earned money, ask friends or neighbours if they have one. It's the kind of thing that almost everyone will have in their drawer of "might be handy one day" odds and ends, and will be glad to see the back of! You usually get sent a couple every time you change broadband providers or request a new router. You can't move for the damn things at most car boots, WEEE bins, charity shops etc.
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Old 23rd Nov 2021, 10:48 am   #14
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

Quote:
Originally Posted by rambo1152 View Post
That's odd, are you saying you moved the VM router and adapter cable from the old house (where the 746 phone rang) to the new house (where it doesn't)?
Yes, that's correct. When we moved to this flat.
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Old 23rd Nov 2021, 10:55 am   #15
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

Quote:
Originally Posted by dagskarlsen View Post
I was able to dig out the F version of the diagram, it should be equal.
I have marked straps with red for use without master socket/adapter with capacitor. I guess it will work nice without the blue strap (try it out after the ringing is back) The other straps (black) should be left as they are, they are not important in hence of ringing, an the rest is working so do not move them. The 3.3 k ohms resistor is one we do not agree about the need, I would usually had a strap there too, and that may be worth to test out if the red straps do not solve the ringer problem. The resistor is there to reduce the load of the ringer to allow more telephones at the line at the same time. If you have a resistor there today, do not change it just because of the value, (someone has put it in to do that job described for the 3k3 resistor) but you may test to strap it.
Thanks, I will try this out tonight. I just need to link the Tx which are shown in red right?
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Old 24th Nov 2021, 1:45 pm   #16
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Default Re: (8)746G DFM 83/2 - Stopped ringing, need pointers on trouble shooting

Yes
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