• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

anyone have a project to make a caller id circuit?

Status
Not open for further replies.

adrian120

New Member
I'd like to build a caller id circuit to connect to my telephone line. Anyone know if there are any of these projects?
 

crust

Member
I have used the motorola mc145447. It works well, but if you want to interface something to a complex enough machine, just use an old caller id modem.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
adrian120 said:
i'm in the uk
In that case you should be aware that the UK uses a different caller ID system to the USA. You should also be aware that you are not allowed to connect non-approved apparatus to the UK telephone network (and approval costs in the thousands, if not tens of thousands), it's seriously frowned upon, and carries unlimited fines.
 

adrian120

New Member
no i did not as i have not been living in the uk all that long...

maybe you could give me some info on a IR filter? i need a filter to block out ambient light and sunlight for a ir photo diode. looked at maplins and rs no luck, found a internet site but that was quite expensive. your input would be helpfull, thank you.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
adrian120 said:
maybe you could give me some info on a IR filter? i need a filter to block out ambient light and sunlight for a ir photo diode. looked at maplins and rs no luck, found a internet site but that was quite expensive. your input would be helpfull, thank you.
IR filters only tend to have a limited effect, they reduce visible light, not block it all together - the casing of the photo-diode already incorporates an IR filter, and you have found how effective that one is!.

What are you trying to do with the photo-diode?, the usual way of overcoming ambient light is to apply modulation to the IR transmitter, and check for this modulation in the receiver. You can buy special three pin IC's which do all this, they are commonly used as IR remote receivers in TV's etc.
 

adrian120

New Member
i'm am using this circuit as a remote extender from one to room to control a satalite box for tv in another room. LED1 in the circuit in a normal LED which when recieves a signal via the photodiode (sfh2030) will flash. LED1 stays on all the time unless it is in near darkness, thats why i need some way to filter out unwanted light. LED0 is the ir emitter diode.
 

Attachments

Nigel Goodwin

Super Moderator
Most Helpful Member
adrian120 said:
i'm am using this circuit as a remote extender from one to room to control a satalite box for tv in another room. LED1 in the circuit in a normal LED which when recieves a signal via the photodiode (sfh2030) will flash. LED1 stays on all the time unless it is in near darkness, thats why i need some way to filter out unwanted light. LED0 is the ir emitter diode.
The circuit doesn't look very practical, with no -ve supply to the opamp it's liable to be holding the transistor permanently on anyway. Have you considered AC coupling the transistor?, the incoming IR is modulated with a 38KHz carrier - you don't need to pass any DC content (because there is none!).

IR remote extenders are freely available, and usually work well, and probably are not as crude as this one - if your satellite is a Sky Digibox you can get a 'magic eye' which sends IR back down the aerial lead into RF2. This is a far better solution, is very cheap, freely available, and uses the existing aerial wire.
 

adrian120

New Member
i have tried those "one for all" remote extenders but they did not work. the magic eye won't work because i have a telewest cable box. the circuit does seem it work but the photodiode is just picking up too much unwanted light. if it is covered up in near darkness it works ok. as for ac coupling the transistor i'm not that clued up - sorry!
 
Status
Not open for further replies.

EE World Online Articles

Loading
Top