This works, dont worry I try this and working like a charm.
I found one mistake in circuit for 1 Relay control.
On PCB "plocica_bot.gif" resistor 10K and capacitor 0,1uF should swap places.
Also I must change 10K with 6,8K resistor on input of 8870 IC , I get very low sound and low level sound DTMF. With lowering resistor value I get DTMF more stronger. If you have similar problem do the same or put even lower 4,7K resistor.
I use small isolation telephone line isolation transformer from some old modem, and I made some redesign of PCB for other type and shape of relay. This trafo impedance should be 1:1 600R:600R impedance, because telephone line have 600R impedance, in US & Canada they have I think 900R but not sure for them.
All of this like devices must be installed after ADSL filter, NOT before ADSL filter.
This device in both versions have password to access device.
To make this to work well you must program and configure uC.
560R have rule to reduce load on line if output is connected to very low impedance. You can use also 620R resistor.
Non polarised capacitor is placed in serie with transformer line to prevent DC current from flowing in the transformer winding which may prevent the line from returning to the on-hook state. Use at least 400V voltage ratings.
Varistor on line input VDR 500V, can be omitted. Also you can get this varistor from almost any good quality PC modem.
On 4N35 optocoupler you can sense anything what you whant, 220V is just given like example to see if device is turned on or off (on power). You can sense lower voltages just adjust resistor and exclude diode if is DC current.
You can use solid state relays instead coil relay, or you can use small relays to switching contactors which controls some three phase or single phase central heating oven or something else powerful.
In SMD variant this complete device can be very small.
File "plc.lay" is PCB made with sPrint-Layout software.
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According to your posted parts of circuit which you try, and you say didnt work do the following :
Replace 220nF/400V with 100nF/400V and must be non polarised capacitor.
Lower resistor value of 100K of 8870 input to 10K/6,8K/5,1K/4,7K.
Check isolation transformer that is 1:1 600R:600R impedance.
Do you did well programming of uC?
uC is working-good and without damages?
On your posted circuit quartz dont have needed capacitors of 22pF connected to ground!
I think you get enough information to start making this project.
After this you can go to SMS remote sensing and control.
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