I believe that I finally figured this out.

Relay #3 is normally closed so that outgoing phone calls can be made anytime.

When a call comes in it will be categorized by the Arduino as one of three types.
White List: A known phone number that I want to ring the house phones
Black List: A known phone number that I do not want to ring the house phones
Unknown: An unknown phone number

When a call comes in it is first detected by “Ring Detection”. Relay #1 is normally closed so the signal travels to Relay #3. Relay #3 then opens and no ringing will occur in the house during this period of determining what type of call we have. HT9032D looks for the phone number which occurs between the first and second rings. The Arduino then categorizes that phone number as White List, Black List, or Unknown.

If it’s a “White List” number then Relay #1 is opened which then closes Relay #3. House phones start to ring.

If it’s a “Black List” number nothing happens. When the caller gives up, “Ring Detection” stops signalling. Relay#3 closes. Everything is back to were it was before the call. And the house phones never rang once.
View attachment 282646
If it’s an “Unknown” number Relay #2 closes and the telephone line is connected to the XE0068DT chip. The XE0068DT tells the Arduino that it opened the phone line (OH). The Arduino then sends out the outgoing message (“Press 21 to continue”). The XE0068DT listens for a DTMF from the caller and sends the information to the Arduino. The Arduino checks the incoming DTMF (or nothing) against the DTMF requested and determines if it’s a real person calling or not (telemarketer). If it’s the correct DTMF Relay #1 is opened thereby closing Relay #3 and the house phones start ringing. Otherwise nothing happens. The house phones never ring once.

I just found a mistake. If the XE0068DT "answers" the phone, the phone ringing STOPS. I need to add a ringtone generator. If the caller DTMF's the correct number, the phone ringing in the house needs to start ringing but the signal will not be coming from the VOIP.

A funny twist would be to have a recording of a 'raspberry' and have that played into the phone instead of 'hello' (ha ha).

 

There is this module built around the HT9032 that @Reloadron mentioned. It has all the necessary isolation already done. It seems worth the cost just for that.

View attachment 275190​

I ordered mine from eBay as well - got is MUCH faster than I expected. Now I just need to figure out how to connect it to my Arduino UNO R4. and use it.

 

And what we see in the photo is all that the buyer received. not even a hint about the supply voltage required.
Good luck with decoding the output stream.

 

And what we see in the photo is all that the buyer received. not even a hint about the supply voltage required.
Good luck with decoding the output stream.

What?

​

and, the chip in that board is a very well known Holtek part with a complete datasheet. The digital is the standard CID stream, also very well documented with plenty of Arduino projects for CID from which code can be found.

Also, there‘s this earlier post in the thread—which you liked.

 

OK, it seems that I did not look close enough at the photo.
Now what we need is a scheme to detect spoofed caller IDs.
Actually, what we need is a revision in the laws to make spoofing a caller ID a crime, so that I can avoid that 15 to 20 calls a day trying to rip me off somehow.

 

I have an Ooma VOIP system.
It has extensive options for blocking junk calls, such as by area code, so I only get a few a week that ring through.

One nice option is, it allows voice-mail recording of blocked calls without letting them ring.
That allows you to catch a message from a desired call, even if is being inadvertently blocked.
I do often get one or two recorded junk voice-mails a day without any ring, but they are easily deleted in the Ooma computer app.

I set up my cordless phones, connected to the Ooma box, to record any voice-mail from calls that ring through.
They also, of course, show the caller ID.
So basically my cordless phones act like they are connected to a land-line, but without most of the junk calls getting through.

 

I have an Ooma VOIP system.
It has extensive options for blocking junk calls, such as by area code, so I only get a few a week that ring through.

One nice option is, it allows voice-mail recording of blocked calls without letting them ring.
That allows you to catch a message from a desired call, even if is being inadvertently blocked.
I do often get one or two recorded junk voice-mails a day without any ring, but they are easily deleted in the Ooma computer app.

I set up my cordless phones, connected to the Ooma box, to record any voice-mail from calls that ring through.
They also, of course, show the caller ID.
So basically my cordless phones act like they are connected to a land-line, but without most of the junk calls getting through.

I‘ve got something similar here but I use a cloud-based VoIP service and a variety of termination equipment. I have a 6 station DECT 6 wireless phone system which is only occasionally used. Mostly the calls that go through go to my, or my wife’s, or both mobile phones. Voice mail is notified by email.

On our home number the recording says to press 5 if you want to try to ring us, otherwise leave a message. Spam calls almost universally hang up before the recording times out. I haven’t gotten a spam call on my home line for at least a year if not longer.

I also have CID-based blocking for some numbers, with a variety of possible recordings that play depending on which number is calling. Some, such as collection agencies who’ve gotten hold of our number because someone said it was theirs, hear:

<SIT PERMANENTLY DISCONNECTED TONES>
The number you have reached has been disconnected or is no longer in service. If you think you reached this number in error, please hang up and dial again, or call your operator for assistance.
<PAUSE>No further information is available
<REORDER TONES>

Calls without caller ID get:

<SIT TONES>
This number cannot be reached without a valid caller ID.
<PAUSE>
<REPEAT>
<REORDER TONES>

I also have other niceties such as DISA (Direct Inward System Access) so I can call from my home number by dialing in and getting a dial tone, FAX send and receive, call recording, and audio conferencing.

 

BTW:
does voip have caller ID "tones" as POTS does ?

YES tones

 

Now this has got my interest going: "I have an Ooma VOIP system. It has extensive options for blocking junk calls, such as by area code, so I only get a few a week that ring through. "
I have been getting 15 to 20 assorted calls every day, all intending to somehow steal from me while claiming to deliver some amazing benefit.
And, last night we got a call at 1:02 AM.
So a system that can deal with the calls that have spoofed caller IDs would be a great benefit.
Presently we have the "WOW" cable phone service, which has not impressed me as being great.
So is any more information about the "Ooma VOIP system" available??

My preferred solution would be a legal change to make caller-ID spoofing an identity-theft crime so that it could be prosecuted adequately. But I doubt this would be accomplished without some serious legal theory assistance.

 

Now this has got my interest going: "I have an Ooma VOIP system. It has extensive options for blocking junk calls, such as by area code, so I only get a few a week that ring through. "
I have been getting 15 to 20 assorted calls every day, all intending to somehow steal from me while claiming to deliver some amazing benefit.
And, last night we got a call at 1:02 AM.
So a system that can deal with the calls that have spoofed caller IDs would be a great benefit.
Presently we have the "WOW" cable phone service, which has not impressed me as being great.
So is any more information about the "Ooma VOIP system" available??

My preferred solution would be a legal change to make caller-ID spoofing an identity-theft crime so that it could be prosecuted adequately. But I doubt this would be accomplished without some serious legal theory assistance.

Hi,

I think the main issue is enforcement. Some of the calls come from outside the US so they would not be able to prosecute unless the global community got in on it. That, and the sheer number of robo-callers.

 

Certainly enforcement would take some effort, no argument about that. but like all crimes, enforcement tends to reduce the number of crimes committed. And given that identity theft for the purpose of criminal fraud is serious, any amount would be a benefit.
And for the calls coming from outside the US, the rapid cure would be to disconnect the source country from internet access to the US. My guess is that the callers would be silenced within 24 hours, at the most. Other governments sometimes move much faster when profit is at stake.

 

Certainly enforcement would take some effort, no argument about that. but like all crimes, enforcement tends to reduce the number of crimes committed. And given that identity theft for the purpose of criminal fraud is serious, any amount would be a benefit.
And for the calls coming from outside the US, the rapid cure would be to disconnect the source country from internet access to the US. My guess is that the callers would be silenced within 24 hours, at the most. Other governments sometimes move much faster when profit is at stake.

Hello,

Did you try going to your local police station or calling them to report the offenses?
If you are on the "no call" list that could help, for a while anyway.

 

The problem withthe police option is that so far caller-ID spoofing is not a criminal act, and so they are not obligated to do anything. So the fist step is to get the law changed, and unfortunately that takes lots of money.

 

The problem withthe police option is that so far caller-ID spoofing is ot a criminal act, and so they are not obligated to do anything. So the fist step is to get the law changed, and unfortunately that takes lots of money.

Even if it were made illegal, how would you enforce it, since most of the calls originate overseas?
I don't think cutting off internet access to those countries is practical (or perhaps even possible).

 

There have been changes made that make out of country calls terminating here impossible to spoof directly, and for people needing to prove the CID is a number they control before doing it. It has meant a very big reduction in the spoofing.

On the other hand, they can still buy DIDs in the areas they want to call—a different problem.

 

The problem withthe police option is that so far caller-ID spoofing is ot a criminal act, and so they are not obligated to do anything. So the fist step is to get the law changed, and unfortunately that takes lots of money.

Hi,

Well you just got your wish, and the wish of everyone in the country...

The FCC just closed major loopholes used by businesses and scammers to send an avalanche of unwanted calls and texts (msn.com)

One major change was that the Do Not Call registry will now include texts.

 

Hi,

Well you just got your wish, and the wish of everyone in the country...

The FCC just closed major loopholes used by businesses and scammers to send an avalanche of unwanted calls and texts (msn.com)

One major change was that the Do Not Call registry will now include texts.

Very interesting indeed. Definitely a move in the right direction, BUT there was not one word about spoofing caller-ID signals, other than requiring some calls to prove that they control the number they present. This gets around number blocking
Also, does intended fraud fall inside the definition of telemarketing?? Criminal intent is not marketing by a normal definition. So until faking an identity is made a crime all in itself, the effort is not adequate.
Of course, if some individual creates a device that detects spoofed caller IDs, they will have an instant market for all that they can deliver, at any even twice the reasonable price.

 

Very interesting indeed. Definitely a move in the right direction, BUT there was not one word about spoofing caller-ID signals, other than requiring some calls to prove that they control the number they present. This gets around number blocking
Also, does intended fraud fall inside the definition of telemarketing?? Criminal intent is not marketing by a normal definition. So until faking an identity is made a crime all in itself, the effort is not adequate.
Of course, if some individual creates a device that detects spoofed caller IDs, they will have an instant market for all that they can deliver, at any even twice the reasonable price.

And that's a very interesting idea. However, at the moment I do not know any way to detect a spoofer. I know how to detect and decode caller ID, but that's about it. I can tell the number from the caller ID electronically and act on it, but that action would be limited to guess work, kinda.
If you have any idea how such a thing might work, maybe one of us can build such a device.

Another problem is that some cell phones are given area codes that do not look like the usual area codes for the given area.

 

I wonder about the timing of the tones and how exact the frequency control is. What would be good is if there was an exact frequency shift that could be used to prove a code was legitimate. Not a big shift, or better yet, duty cycle modulation. And better still, different wave forms for the different tones.

 

I wonder about the timing of the tones and how exact the frequency control is. What would be good is if there was an exact frequency shift that could be used to prove a code was legitimate. Not a big shift, or better yet, duty cycle modulation. And better still, different wave forms for the different tones.

Hi,

Yes that's interesting there could be subtle difference, although it would have to be measurable.
One thing is that you can do this yourself just by going online and looking for sites that allow you to send texts via a phone number that they supply. There are multiple numbers to choose from too, and they may vary them over time. You can send texts but if you get a reply, you have to look through the list of replies to find yours out of several because someone else could use the same number 5 minutes after you were done using it and they could have gotten a reply also.
How exactly they generate these numbers and put them into effect would be something to look into.