small circuit help needed

B

Bob in PHX

Guest
To All,
I have an interesting problem that I need to solve. I have an older
electronic blackjack machine that has blown the coin hopper pay out circuit.
No schematic of the board is available and the pcb has a 25 cent sized
burned clean through it.... The good part is that I found a chip that puts
out a 5 volt signal when the "jackpot" is hit and the coin hopper needs to
start. This 5volt signal stops when the jackpot has been paid.

I was thinking that a simple relay would work, but then I worried about
pulling to much amperage out of the chip, which by the way is some sort of
specialty chip, thus I don't know what the chip can stand. So, I figure that
I need some sort of opto isolator chip that has a very small amperage draw.
This chip would allow me to use a separate power supply to trigger the
relay, with say a 2n3904 transistor.... I just don't know what chip to use
that would isolate the 5v trigger lead from a separate 5v powered circuit.
The two circuits would not share a ground.

any ideas??????

Bob in phx....
 
On Sun, 20 Feb 2005 16:34:33 -0700, "Bob in PHX" <rbelisle1@cox.net>
wrote:

. I am guessing a
1000 ohm resistor?????
Click to expand...
---
Yup.
---

Second, the ground show comes from the second power supply or from the same
ground as the trigger???
Click to expand...
---
If you can get the current you need to run the relay from the trigger
supply, then it's the trigger supply ground. If you have to use a
different supply, then tie the trigger supply and the relay supply
grounds together.

--
John Fields
 
Thanks for all the help... Ill try it out this week and report back the
results!!!!!

Bob in phx
"John Fields" <jfields@austininstruments.com> wrote in message
news:80di11lcc1upo0bvbg8s0qltk09sbado36@4ax.com...
On Sun, 20 Feb 2005 16:34:33 -0700, "Bob in PHX" <rbelisle1@cox.net
wrote:

AWSOME!!!!!!!! Only two questions. What is the [1000r]. I am guessing a
1000 ohm resistor?????

---
Yup.
---

Second, the ground show comes from the second power supply or from the
same
ground as the trigger???

---
If you can get the current you need to run the relay from the trigger
supply, then it's the trigger supply ground. If you have to use a
different supply, then tie the trigger supply and the relay supply
grounds together.

--
John Fields
Click to expand...
 
IT WORKS,,,, IT WORKS!!!!!!!!! I built the suggested circuit, powered it
from a separate 5v power supply, tied the grounds together and it
works!!!!!!!

John, Your the best!!!!!

Thanks a million.... Off to play the slots,,, in my own house!!!!!!!!

bob in phx



"Bob in PHX" <rbelisle1@cox.net> wrote in message news:...
Thanks for all the help... Ill try it out this week and report back the
results!!!!!

Bob in phx
"John Fields" <jfields@austininstruments.com> wrote in message
news:80di11lcc1upo0bvbg8s0qltk09sbado36@4ax.com...
On Sun, 20 Feb 2005 16:34:33 -0700, "Bob in PHX" <rbelisle1@cox.net
wrote:

AWSOME!!!!!!!! Only two questions. What is the [1000r]. I am guessing a
1000 ohm resistor?????

---
Yup.
---

Second, the ground show comes from the second power supply or from the
same
ground as the trigger???

---
If you can get the current you need to run the relay from the trigger
supply, then it's the trigger supply ground. If you have to use a
different supply, then tie the trigger supply and the relay supply
grounds together.

--
John Fields
Click to expand...
 
On Sun, 20 Feb 2005 12:12:35 -0700, "Bob in PHX" <rbelisle1@cox.net>
wrote:

To All,
I have an interesting problem that I need to solve. I have an older
electronic blackjack machine that has blown the coin hopper pay out circuit.
No schematic of the board is available and the pcb has a 25 cent sized
burned clean through it.... The good part is that I found a chip that puts
out a 5 volt signal when the "jackpot" is hit and the coin hopper needs to
start. This 5volt signal stops when the jackpot has been paid.

I was thinking that a simple relay would work, but then I worried about
pulling to much amperage out of the chip, which by the way is some sort of
specialty chip, thus I don't know what the chip can stand. So, I figure that
I need some sort of opto isolator chip that has a very small amperage draw.
This chip would allow me to use a separate power supply to trigger the
relay, with say a 2n3904 transistor.... I just don't know what chip to use
that would isolate the 5v trigger lead from a separate 5v powered circuit.
The two circuits would not share a ground.
Click to expand...
---
View using a fixed pitch font:

+5V
|
+----+----+
|K |
[1N4001] [COIL]- - -|
| | +--> |
+----+----+ | |
| O O--->TO COIN HOPPER
C |
5V TRIGGER>----[1000R]----B 2N4401 +-------->TO COIN HOPPER
E
|
GND>------------------------+


--
John Fields
 
AWSOME!!!!!!!! Only two questions. What is the [1000r]. I am guessing a
1000 ohm resistor?????

Second, the ground show comes from the second power supply or from the same
ground as the trigger???

Thanks for the design and in advance for the answers to my two questions!!!

Bob in phx
"John Fields" <jfields@austininstruments.com> wrote in message
news:bb3i11pptngl04o7r5bmubb4sfu3h99a5g@4ax.com...
On Sun, 20 Feb 2005 12:12:35 -0700, "Bob in PHX" <rbelisle1@cox.net
wrote:

To All,
I have an interesting problem that I need to solve. I have an older
electronic blackjack machine that has blown the coin hopper pay out
circuit.
No schematic of the board is available and the pcb has a 25 cent sized
burned clean through it.... The good part is that I found a chip that
puts
out a 5 volt signal when the "jackpot" is hit and the coin hopper needs to
start. This 5volt signal stops when the jackpot has been paid.

I was thinking that a simple relay would work, but then I worried about
pulling to much amperage out of the chip, which by the way is some sort of
specialty chip, thus I don't know what the chip can stand. So, I figure
that
I need some sort of opto isolator chip that has a very small amperage
draw.
This chip would allow me to use a separate power supply to trigger the
relay, with say a 2n3904 transistor.... I just don't know what chip to use
that would isolate the 5v trigger lead from a separate 5v powered circuit.
The two circuits would not share a ground.

---
View using a fixed pitch font:

+5V
|
+----+----+
|K |
[1N4001] [COIL]- - -|
| | +--> |
+----+----+ | |
| O O--->TO COIN HOPPER
C |
5V TRIGGER>----[1000R]----B 2N4401 +-------->TO COIN HOPPER
E
|
GND>------------------------+


--
John Fields
Click to expand...
 
On Sun, 20 Feb 2005 16:34:33 -0700, Bob in PHX wrote:

. I am guessing a
1000 ohm resistor?????

Second, the ground show comes from the second power supply or from the same
ground as the trigger???
Click to expand...
For the circuit[0] to work as shown, both grounds (for the trigger source
and for the relay supply) need to be common (connected together). Since
the relay contacts are isolated, it doesn't matter where ground is in the
payout circuit, as long as the difference doesn't break down the relay
insulation, which is very unlikely.

Good Luck!
Rich

[0]
---
View using a fixed pitch font:

+5V
|
+----+----+
|K |
[1N4001] [COIL]- - -|
| | +--> |
+----+----+ | |
| O O--->TO COIN HOPPER
C |
5V TRIGGER>----[1000R]----B 2N4401 +-------->TO COIN HOPPER
E
|
GND>------------------------+
--
John Fields
Click to expand...
 
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