DreamPi connection - line busy??

[Gary_b]

Yes, it looks like you are using the wrong components. The resister that is connected to the Negative line looks correct, but the other one should be an electrolytic capacitor. I will link to the ones that I ordered. I do not know if you need a special one for your PAL setup, but these are 50 volt caps so perhaps they will work for both NTSC and PAL inducers.
http://www.ebay.com/itm/251416914232?_t ... EBIDX%3AIT

[macaronielevator]

Oh okay, I'm a bit of an amateur with circuitry so thanks for your help. Just out of interest what type of capacitor was I using? It was the same 0.47 uf value as the one you linked to me

[Gary_b]

I can't tell by looking at it. Maybe a ceramic or one of the many other forms. The kind you need is going to be in a tube shape. I would ask another pal user what one they used. I would think that the ones I linked to will work for you but it would be nice to have confirmation on that before you buy them. If you have any old electronics laying around you might be able harvest one. I do not know if you can run them in a series like the batteries in the event they are not strong enough, but the auction does come with two.

[macaronielevator]

Cool, really appreciate the help! Hopefully will be able to get online soon

[kazade]

FWIW, the 470 Ohm resistor will probably only work with 18v (just in case anyone non-PAL tries it).

Generally, phone lines have around 25-40 milliamps of current on the line when in use. 9v / 330 Ohm = 27 milliamps, 18v / 330 = 54 milliamps (which is a little high maybe, but it works fine, 380 Ohm is probably better for PAL).

As you're using 18 / 470 you still get 38 milliamps which is good, but if you were using non-PAL 9v, then you'd be getting like 17 milliamps which would probably cause problems.

[Gary_b]

FWIW, the 470 Ohm resistor will probably only work with 18v (just in case anyone non-PAL tries it).

Generally, phone lines have around 25-40 milliamps of current on the line when in use. 9v / 330 Ohm = 27 milliamps, 18v / 330 = 54 milliamps (which is a little high maybe, but it works fine, 380 Ohm is probably better for PAL).

As you're using 18 / 470 you still get 38 milliamps which is good, but if you were using non-PAL 9v, then you'd be getting like 17 milliamps which would probably cause problems.

He also needs to know what capacitor to use as well. I linked to the one that I used for my NTSC inducer. It is a 50 volt 47uf cap. What I do not know is if you need to use a higher voltage cap like a 100 volt 47uf cap for the PAL Inducer? Or will the same one work for either setup?

[kazade]

It should always be a 0.47uf electrolytic capacitor (note 0.47, not 47) to block out DC noise. As long as it can deal with 18V (which is pretty much all of them) it should be fine.

[Gary_b]

It should always be a 0.47uf electrolytic capacitor (note 0.47, not 47)

My mistake, I did link to the actual item and they are in fact .47 microfarads.

[macaronielevator]

It should always be a 0.47uf electrolytic capacitor (note 0.47, not 47) to block out DC noise. As long as it can deal with 18V (which is pretty much all of them) it should be fine.

I've ordered some 50v 0.47uf electrolytic capacitors. Should I still use the 470 ohm resistor or would you recommend buying some 380 ohm resistors and rebuilding the whole circuit since I'm using a PAL modem? Really appreciate the help!

[kazade]

I think you *should* be OK with the 470 Ohm, if I understand the circuit right. If you continue having trouble though that would be the next thing to look at