not sure what's up with the smiley faces. I built the list in Notepad then copied/pasted..

 

RELAY
4-PIN NO 40/30 AMP 12VDC

You are in the ball park.
The relay appears to be an automotive type, helpful to know the coil resistance or can you provide a link or model #
Resistors only need to be 1/4 watt, the .82uf cap at 200 volts is sufficient.
May need to change the transistor components depending on the relay you select.

 

Thank you. this is what I have:

 

I‘ll order the correct components when I figure them out. Just thought I’d share these pics of stuff I had laying around but never did anything with. Sghioto, I’ll get the coil resistance specs on that automotive relay asap and read up on the relationship to the transistor. Thank you

 

I’ll get the coil resistance specs on that automotive relay asap

Not necessary, I see a relay in the photo that will work. It's the one marked Song Chuan 301-1A-C-R1-U03
The parts you listed in post #20 do you have those on hand?

 

Not necessary, I see a relay in the photo that will work. It's the one marked Song Chuan 301-1A-C-R1-U03
The parts you listed in post #20 do you have those on hand?
View attachment 256249

from post #20 I have :
-22K 1/2W carbon film resistors (maybe would work for R1 on schematic)
-3.9K 1/2W carbon film resistors (not sure if these can be used for R2/R3)

I also have an arduino uno and a relay shield that has a photo coupler. I'm going to look into that this evening.

I'll probably place orders for parts tomorrow. I spent the better part of today reading and installed a program called LTspice and replicated the schematic in this post and kind of got it working but got hung up on replicating the power source from the phone speaker wires. I did notice that LTspice had matching component brands for C1 (kemet 0.82uF), C2 (wurth electrolytic 1uF), and D2 (RR1LAM6S) so that was pretty cool.

I'll keep reading up on this stuff. There's lots of info online and I need to get a handle on the fundamentals of semiconductors. Also need to figure out how I'm going to connect all of these. I can -kind of- solder so I'll figure that out too.

Thank you for your help any feedback is appreciated!

 

The resistors you have will work along with the relay I mentioned before.
The Arduino would fun to test out but way overkill for this project.

kind of got it working but got hung up on replicating the power source from the phone speaker wires.

The photo coupler is powered from the telephone line not the phone speaker wires. The power from the phone line is the ringer signal, typically 90 volts peak to peak at 20Hz, try that in your simulation.

 

The resistors you have will work along with the relay I mentioned before.
The Arduino would fun to test out but way overkill for this project.

The photo coupler is powered from the telephone line not the phone speaker wires. The power from the phone line is the ringer signal, typically 90 volts peak to peak at 20Hz, try that in your simulation.
View attachment 256287

Thank you. Maybe I gave the wrong info. This is the unit and I'm trying to use the analog speaker voltage that normally energizes the internal 8ohm 2W ring speaker. These are 2-way 900Mhz intercoms

 

OK I see that now. Just forget the circuit I posted it's not going to work in this application. Do you have a scope to view the voltage across the speaker when it's ringing?

 

OK I see that now. Just forget the circuit I posted it's not going to work in this application. Do you have a scope to view the voltage across the speaker when it's ringing?

I have a fluke multimeter but not a scope. Haven't had a chance to read the manual yet..

When phone rings and multimeter probes are on piezo speaker solder points:

With multimeter set to AC the readout jumps from (roughly) 13mV to 490mV to 13mV to 490mV until ringing stops

With multimeter set to Hz the readout looks like 28 - 46 - 362 - 46 - 28 -46 - 362 etc..

With multimeter set to DC it just shows 0

I've attached several pics and included the big speaker that I'm trying to activate. Thank you for the help

 

It's possible to use that ringer signal to activate a relay but how are you going to use the phone if it has wires coming out to some external circuit?

 

It's possible to use that ringer signal to activate a relay but how are you going to use the phone if it has wires coming out to some external circuit?

Phone will be in an intrinsically safe box (probably will need external antenna) and 2 wires will run to the horn. I’m -told- that 2 phones can be set to the same extension, so if Sghioto and the horn-phone are both extension 15, you hear the horn, then grab your phone to answer. Your phone will have rang too, but the environment prevents you from hearing it. Not counting on that though.

Most likely the setup will be: you hear the horn on (activated from phone 15) then grab your phone (16) expecting a call in the next few seconds

 

Phone will be in an intrinsically safe box (probably will need external antenna) and 2 wires will run to the horn. I’m -told- that 2 phones can be set to the same extension, so if Sghioto and the horn-phone are both extension 15, you hear the horn, then grab your phone to answer. Your phone will have rang too, but the environment prevents you from hearing it. Not counting on that though.

Most likely the setup will be: you hear the horn on (activated from phone 15) then grab your phone (16) expecting a call in the next few seconds

short answer: horn phone’s only purpose is to ultimately sound a loud horn/siren

 

short answer: horn phone’s only purpose is to ultimately sound a loud horn/siren

It's possible to use that ringer signal to activate a relay but how are you going to use the phone if it has wires coming out to some external circuit?

The phone also has a 2.5mm audio jack for earpiece/hearing aide. I don’t have a 2.5 male to check with multimeter, but I’m sure there’s a standard. I’ll do more reading.

Again, thank you for the help

 

The phone also has a 2.5mm audio jack for earpiece/hearing aide.

Will the ring tone come through the audio jack?
I have a couple of ideas but need some more detail on the ring tone.
What does it sound like?
Is it like a standard ring signal, ON for 2 seconds, OFF for 4 seconds then repeat?