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# Telephone circuit advice

D

#### Diefenbaker

Jan 1, 1970
0
Im looking at building the Smart Phone Light at

http://www.electronic-circuits-diagrams.com//telephonesimages/12.gif

It looks relatively easy for a novice. My question is regarding the +5v
coming off or perhaps better said going to the IC3 (A) Pin 16.
Does this mean that I should use an AC/DC adaptor to apply DC +5 volts here.
And does the negative of this go to the Ground symbol at the bottom.

Thanks.

C

#### CFoley1064

Jan 1, 1970
0
Subject: Telephone circuit advice
From: "Diefenbaker" [email protected]
Date: 12/14/2004 12:32 PM Central Standard Time
Message-id: <[email protected]>

Im looking at building the Smart Phone Light at

http://www.electronic-circuits-diagrams.com//telephonesimages/12.gif

It looks relatively easy for a novice. My question is regarding the +5v
coming off or perhaps better said going to the IC3 (A) Pin 16.
Does this mean that I should use an AC/DC adaptor to apply DC +5 volts here.
And does the negative of this go to the Ground symbol at the bottom.

Thanks.

Hi. It does mean you'll need an external power source. Since you've got TTL,
you'll need a well-regulated 5VDC +/- 0.25V supply for this to work.

If you've got a little room, get a 9 to 12VDC wall wart, a 7805CT regulator and
a couple of 10uF, 25V electrolytic caps and do something like this (view in
fixed font or M$Notepad): ____ | | o------o---|7805|---o------o | 1|____|3 | | 2| | +| | +| 5VDC OUT 9VDC IN --- | --- --- | --- | | | | | | | | | | | | o------o-----o------o------o created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de Pin numbers on the 7805 are looking from the front (plastic side) of the TO-220 package, pins down, from left to right. These parts will be available at any hobbyist source. This will give you the regulated 5VDC you need. And, oh yes. The negative side goes to the GND symbol at the bottom. Good luck Chris D #### Diefenbaker Jan 1, 1970 0 Jamie said: it means you should be using a regulated source or a source that is rather stable around 5 volts to power up the circuit. would this be used to detour some one into thinking your home if the phone rings? or simply an auto night lamp when the phone rings to see your way to the phone? I'm the first guy called when the alarm goes off for the company. I hate fumbling around in the dark. Im sure I could buy somthing like this, for less than it will cost to make. But what would be the fun in that? If anyone could answer the following question as well... I have tried to buy (C1) 1.u 400v Capacitor. But my local guys dont have anything like this. Could I use something else. I did see 1u 250v but 400v seems a little excessive, acept for spikes I suppose but I think everything would go if it got that high. Secondly Im asuming that the +1000 could be a 16v cap. Finally the Relay I guess needs to be 5v relay. The diagram smudges the number. But asuming that the voltage there is 5v DC. Thanks. D #### Diefenbaker Jan 1, 1970 0 CFoley1064 said: Hi. It does mean you'll need an external power source. Since you've got TTL, you'll need a well-regulated 5VDC +/- 0.25V supply for this to work. If you've got a little room, get a 9 to 12VDC wall wart, a 7805CT regulator and a couple of 10uF, 25V electrolytic caps and do something like this (view in fixed font or M$ Notepad):

____
| |
o------o---|7805|---o------o
| 1|____|3 |
| 2| |
+| | +| 5VDC OUT
9VDC IN --- | ---
--- | ---
| | |
| | |
| | |
| | |
o------o-----o------o------o
created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

Pin numbers on the 7805 are looking from the front (plastic side) of the TO-220
package, pins down, from left to right. These parts will be available at any
hobbyist source.

This will give you the regulated 5VDC you need.

And, oh yes. The negative side goes to the GND symbol at the bottom.

Good luck
Chris

Hey Chris thanks for the answer.

Specially on the view in notepad. Do you know how many times Ive looked at
diagrams in news groups and thought why so people put them in cause I dont
know what font and spacing they used. Its given me a whole new perspecive on
some of the diagrams I have seen and passed up because I could not figure
out how they went together. What A fool Ive been.

Thanks.

J

#### Jamie

Jan 1, 1970
0
Diefenbaker said:
Im looking at building the Smart Phone Light at

http://www.electronic-circuits-diagrams.com//telephonesimages/12.gif

It looks relatively easy for a novice. My question is regarding the +5v
coming off or perhaps better said going to the IC3 (A) Pin 16.
Does this mean that I should use an AC/DC adaptor to apply DC +5 volts here.
And does the negative of this go to the Ground symbol at the bottom.

Thanks.
it means you should be using a regulated source or a source that is
rather stable around 5 volts to power up the circuit.
would this be used to detour some one into thinking your home if
the phone rings? or simply an auto night lamp when the phone rings
to see your way to the phone?

A
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