# Help designing a latching electronic switch

M

#### Mark Ashley

Jan 1, 1970
0
Hi there

I am a novice at electronics so please bear with me!

I need to design a latching electronic switch with a momentary push switch
as a trigger. When the trigger is pushed, the switch will latch closed. When
the trigger is pushed again the switch will toggle back to the open
position. The switch needs to be able to break/supply power a 12v relay. If
the circuit loses and regains power the switch should default back to the
open position.

For reasons I won't go in to at this stage it is not possible just to use a
latching switch to supply the power to the relay.

Hopefully someone can help me if this design is possible!

Thanks
Mark

J

#### John Fields

Jan 1, 1970
0
Hi there

I am a novice at electronics so please bear with me!

I need to design a latching electronic switch with a momentary push switch
as a trigger. When the trigger is pushed, the switch will latch closed. When
the trigger is pushed again the switch will toggle back to the open
position. The switch needs to be able to break/supply power a 12v relay. If
the circuit loses and regains power the switch should default back to the
open position.

For reasons I won't go in to at this stage it is not possible just to use a
latching switch to supply the power to the relay.

Hopefully someone can help me if this design is possible!

---
If you can use a single-pole double-throw momentary switch, then
debouncing is easy and the circuit can be put together with a 4013, a
transistor and a handful of passive components. If you have to use a
SPST switch, then it'll have to be debounced differently. Which way
do you want to go?

C

#### Chris

Jan 1, 1970
0
Mark said:
Hi there

I am a novice at electronics so please bear with me!

I need to design a latching electronic switch with a momentary push switch
as a trigger. When the trigger is pushed, the switch will latch closed. When
the trigger is pushed again the switch will toggle back to the open
position. The switch needs to be able to break/supply power a 12v relay. If
the circuit loses and regains power the switch should default back to the
open position.

For reasons I won't go in to at this stage it is not possible just to usea
latching switch to supply the power to the relay.

Hopefully someone can help me if this design is possible!

Thanks
Mark

Hi, Mark. Novice and newbie questions always welcome here.

If you've got half of a CMOS inverter IC (4000-series would include
4049, 4069, 40106, 74C-series include 74C04, 74C14, &c) or three gates
you can set up as inverters (NAND, NOR, &c), this circuit might fill
the bill (view in fixed font or Notepad):

~ Logic Toggle Pushbutton With Power-On Reset
~ VCC VCC
~ + +
~ | |
~ 1N4002| |
~ VCC - C|
~ + ___ ^ C| RY1
~ | .----------|___|--------. | C|
~.33uF | | 22K | | |
~ --- | | '---o
~ --- 1N4002| | |
~ | |\ | |\ |\ | ___ |/
~ o--| >O--|<--o-----| >O---o----| >O--o--|___|-o-| Q1
~ | |/ | |/ | |/ 22K | |>
~ .-. | .-. .-. |
~ 10K | | | 220K| | | | |
~ | | | | | 22K| | |
~ '-' | T '-' '-' |
~ | | --- | || | |
~ | '--o o-------o----||----. === ===
~ === || | GND GND
~ GND SW1 .022uF |
~ |
|
===
GND
created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

Make sure you use a darlington NPN transistor (like the TIP120) to
switch the relay. This keeps the load on the last inverter down to
around 1mA or so, which any CMOS inverter can handle at 12V. This
should be good for any relay coil that draws less than half an amp.

The first inverter with the diode is set up as MML (Mickey Mouse
Logic). It's only active at turn-on, and forces the input of the
second inverter to be low right after turn-on. That means the third
inverter will be low, and your transistor will be off. After a period
set by the R and C (something on the order of 3ms) the output of the
first inverter will be high, and the diode will effectively remove it
from the circuit.

This stuff was borrowed piecemeal from Don Lancaster's CMOS Cookbook,
which is a good intro to digital electronics for newbies. It's
available at Amazon, libraries, and Mr. Lancaster's website:

http://www.tinaja.com/

Good luck
Chris

M

#### Mark Ashley

Jan 1, 1970
0
If you can use a single-pole double-throw momentary switch, then
debouncing is easy and the circuit can be put together with a 4013, a
transistor and a handful of passive components. If you have to use a
SPST switch, then it'll have to be debounced differently. Which way
do you want to go?

Hi John

I can't use SPDT switches easily as the switches are specific (arcade
machine buttons to be precise). The only way I could make them SPDT would be
to attach a relay to each one, but wouldn't that increase the risk of
bouncing?

Perhaps if I explain exactly what I want to do it will be a little clearer.
I have built an arcade machine with 8 momentary SPST switches. These, as
well as a joystick, connect to an xbox pad so I can use it to play xbox
games. Currently I have a SPST toggle switch which energises a 4 pole relay.
When energised this physically disconnects the arcade controls and connects
a normal xbox pad. I want to remove the toggle switch and replace it with a
circuit which will toggle between the arcade controls and the xbox pad only
when I press all of the buttons on the arcade controls at the same time.

Mark

M

#### Mark Ashley

Jan 1, 1970
0
Thanks for this Chris. I will have a look for some information on the IC you
have used in this circuit so I can find which pins I need to connect to.
Unless you fancy saving me some legwork...

Mark

Hi, Mark. Novice and newbie questions always welcome here.

If you've got half of a CMOS inverter IC (4000-series would include
4049, 4069, 40106, 74C-series include 74C04, 74C14, &c) or three gates
you can set up as inverters (NAND, NOR, &c), this circuit might fill
the bill (view in fixed font or Notepad):

~ Logic Toggle Pushbutton With Power-On Reset
~ VCC VCC
~ + +
~ | |
~ 1N4002| |
~ VCC - C|
~ + ___ ^ C| RY1
~ | .----------|___|--------. | C|
~.33uF | | 22K | | |
~ --- | | '---o
~ --- 1N4002| | |
~ | |\ | |\ |\ | ___ |/
~ o--| >O--|<--o-----| >O---o----| >O--o--|___|-o-| Q1
~ | |/ | |/ | |/ 22K | |>
~ .-. | .-. .-. |
~ 10K | | | 220K| | | | |
~ | | | | | 22K| | |
~ '-' | T '-' '-' |
~ | | --- | || | |
~ | '--o o-------o----||----. === ===
~ === || | GND GND
~ GND SW1 .022uF |
~ |
|
===
GND
created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

Make sure you use a darlington NPN transistor (like the TIP120) to
switch the relay. This keeps the load on the last inverter down to
around 1mA or so, which any CMOS inverter can handle at 12V. This
should be good for any relay coil that draws less than half an amp.

The first inverter with the diode is set up as MML (Mickey Mouse
Logic). It's only active at turn-on, and forces the input of the
second inverter to be low right after turn-on. That means the third
inverter will be low, and your transistor will be off. After a period
set by the R and C (something on the order of 3ms) the output of the
first inverter will be high, and the diode will effectively remove it
from the circuit.

This stuff was borrowed piecemeal from Don Lancaster's CMOS Cookbook,
which is a good intro to digital electronics for newbies. It's
available at Amazon, libraries, and Mr. Lancaster's website:

http://www.tinaja.com/

Good luck
Chris

J

#### John Fields

Jan 1, 1970
0
Hi John

I can't use SPDT switches easily as the switches are specific (arcade
machine buttons to be precise). The only way I could make them SPDT would be
to attach a relay to each one, but wouldn't that increase the risk of
bouncing?

Perhaps if I explain exactly what I want to do it will be a little clearer.
I have built an arcade machine with 8 momentary SPST switches. These, as
well as a joystick, connect to an xbox pad so I can use it to play xbox
games. Currently I have a SPST toggle switch which energises a 4 pole relay.
When energised this physically disconnects the arcade controls and connects
a normal xbox pad. I want to remove the toggle switch and replace it with a
circuit which will toggle between the arcade controls and the xbox pad only
when I press all of the buttons on the arcade controls at the same time.

---
OK, that can be easily enough accomplished, depending on what you've
got the eight momentary switches hooked to. Hopefully, you're
switching either Vcc or ground on _all_ of them and we can use
something like an 8-input AND or NAND to decode the all-buttons-down
state and toggle the latch. Can you post a schematic of what you've
got or describe the circuit in a little more detail?

M

#### Mark Ashley

Jan 1, 1970
0
---
OK, that can be easily enough accomplished, depending on what you've
got the eight momentary switches hooked to. Hopefully, you're
switching either Vcc or ground on _all_ of them and we can use
something like an 8-input AND or NAND to decode the all-buttons-down
state and toggle the latch. Can you post a schematic of what you've
got or describe the circuit in a little more detail?

One of the legs of each momentary switch is connected to a common ground,
which comes from a single point on the xbox pad, then daisy chains to each
switch. This includes the four switches for the joystick I think. The other
side of each switch then goes to its own point on the pad. I haven't
measured what is going across the switch when it is closed, but I can do
this if necessary.

Is that enough information? I can post more or a schematic if you need me
to.

I really appreciate all your help!

Thanks
Mark

M

#### Mark Ashley

Jan 1, 1970
0
---
OK, that can be easily enough accomplished, depending on what you've
got the eight momentary switches hooked to. Hopefully, you're
switching either Vcc or ground on _all_ of them and we can use
something like an 8-input AND or NAND to decode the all-buttons-down
state and toggle the latch. Can you post a schematic of what you've
got or describe the circuit in a little more detail?

One of the legs of each momentary switch is connected to a common ground,
which comes from a single point on the xbox pad, then daisy chains to each
switch. This includes the four switches for the joystick I think. The other
side of each switch then goes to its own point on the pad. I haven't
measured what is going across the switch when it is closed, but I can do
this if necessary.

Is that enough information? I can post more or a schematic if you need me
to.

I really appreciate all your help!

Thanks
Mark

S

#### [email protected]

Jan 1, 1970
0
John - how does this look? (open in Andy's ASCII-Circuit or notepad).
Would this layout affect the normal functioning of the switches?

GND 1 2 3 4 5 6 7 8
| | | | | | | | |
| _/ | | | | | | | |
|-o/ o-o-)-)-)-)-)-)-)------o
| | | | | | | | |
| _/ | | | | | | | |
o-o/ o---o-)-)-)-)-)-)--\ | __
| | | | | | | \ o-| \ __
| _/ | | | | | | \ | )--| \ __
o-o/ o-----o-)-)-)-)-)-\ \o-|__/ | )--| \ __
| | | | | | \-----------|__/ | )--| \
| _/ | | | | | /---------------|__/ | )-o
o-o/ o-------o-)-)-)-)-----/ o--------------------|__/ |
| | | | | | |
| _/ | | | | | o-----------------------o
o-o/ o---------o-)-)-)--------o | __
| | | | o-| \ __
| _/ | | | | )--| \ __
o-o/ o-----------o-)-)-----------o-|__/ | )--| \
| | | o-|__/ | )----
| _/ | | | o-|__/
o-o/ o-------------o-)------------------o |
| | |
| _/ | |
o-o/ o---------------o-------------------------o
(created by AACircuit v1.28.6 beta 04/19/05 www.tech-chat.de)

T

#### Terry Pinnell

Jan 1, 1970
0
Mark Ashley said:
Thanks for this Chris. I will have a look for some information on the IC you
have used in this circuit so I can find which pins I need to connect to.
Unless you fancy saving me some legwork...

Those gates in Chris's circuit could be in a variety of ICs, and so
the pins will vary accordingly. For example, here's the circuit
redrawn for a CMOS 4011 Quad NAND:
http://www.terrypin.dial.pipex.com/Images/LatchingSwitch.gif

Note that the circuit uses only 3 of the 4 ('Quad') gates. The two
input pins of the unused gate are therefore shown wired to ground.

J

#### John Fields

Jan 1, 1970
0
One of the legs of each momentary switch is connected to a common ground,
which comes from a single point on the xbox pad, then daisy chains to each
switch. This includes the four switches for the joystick I think. The other
side of each switch then goes to its own point on the pad. I haven't
measured what is going across the switch when it is closed, but I can do
this if necessary.

---
That would be a good idea. I think the switches are wired like this:

Vcc>--+----- - - ----+
| |
[R] [R]
| |
+--+ +--+
| | | |
| O | | O |
| | | |
| O | | O |
| | | |
| | | |
GND>--+--|-- - - ----+ |
| |
OUT1 OUT8

so that each output would be at Vcc until a switch was pressed, and
then it would go to ground for as long as the switch was pressed. If
you could verify that by measuring the output voltages with the
switches open and pressed that would be fine. Also, if you could
determine the values of the resistors and post that information that
Is that enough information? I can post more or a schematic if you need me
to.

A schematic would be ideal.

J

#### John Fields

Jan 1, 1970
0
John - how does this look? (open in Andy's ASCII-Circuit or notepad).
Would this layout affect the normal functioning of the switches?

GND 1 2 3 4 5 6 7 8
| | | | | | | | |
| _/ | | | | | | | |
|-o/ o-o-)-)-)-)-)-)-)------o
| | | | | | | | |
| _/ | | | | | | | |
o-o/ o---o-)-)-)-)-)-)--\ | __
| | | | | | | \ o-| \ __
| _/ | | | | | | \ | )--| \ __
o-o/ o-----o-)-)-)-)-)-\ \o-|__/ | )--| \ __
| | | | | | \-----------|__/ | )--| \
| _/ | | | | | /---------------|__/ | )-o
o-o/ o-------o-)-)-)-)-----/ o--------------------|__/ |
| | | | | | |
| _/ | | | | | o-----------------------o
o-o/ o---------o-)-)-)--------o | __
| | | | o-| \ __
| _/ | | | | )--| \ __
o-o/ o-----------o-)-)-----------o-|__/ | )--| \
| | | o-|__/ | )----
| _/ | | | o-|__/
o-o/ o-------------o-)------------------o |
| | |
| _/ | |
o-o/ o---------------o-------------------------o
(created by AACircuit v1.28.6 beta 04/19/05 www.tech-chat.de)\

---
Probably not, but you've left the input bubble off of the last gate in
the top group, plus the implementatuion would take a NOR, an AND and a
NAND. What I had in mind was more like this:

Vcc
|
+----+----+----+----+----+----+----+
| | | | | | | |
[R1] [R2] [R3] [R4] [R5] [R6] [R7] [R8]
S1___ | | | | | | | |
+--O O--+----|----|----|----|----|----|----|--A
|S2___ | | | | | | | | OR Y--A
+--O O-------+----|----|----|----|----|----|--B OR Y--A ___
|S3___ | | | | | | | | B OR Y-->OUT TO
+--O O------------+----|----|----|----|----|--A | B TOGGLE
|S4___ | | | | | | | | OR Y--+ |
+--O O-----------------+----|----|----|----|--B |
|S5___ | | | | | | | | |
+--O O----------------------+----|----|----|--A |
|S6___ | | | | | | | | OR Y--A |
+--O O---------------------------+----|----|--B OR Y--+
|S7___ | | | | | | | | B SPARE
+--O O--------------------------------+----|--A | +--A
|S8___ | | | | | | | | OR Y--+ | OR Y
+--O O-------------------------------------+--B +--B
| | | | | | | | | |
GND OUT1 OUT2 OUT3 OUT4 OUT5 OUT6 OUT7 OUT8 GND

which uses two quad 2 input NORs; HC32's or CD4071's.

It could also be implemented with a single chip, a dual 4 input OR
(CD4072) and a couple of diodes, like this:

FROM S1>---A

FROM S2>---B ___
Y---[CR1>]--+--->OUT
FROM S3>---C |
|
FROM S4>---D |
|
|
FROM S5>---A |
|
FROM S6>---B |
Y---[CR2>]--+
FROM S7>---C |
[10K]
FROM S8>---D |
GND

It might even be possible to do it with all diodes and resistors,
depending on what Mark's circuit looks like.

J

#### John Fields

Jan 1, 1970
0
---
Unless... Are those all supposed to be ORs and the "o"'s are
connections? If so, then your approach and mine are basically the
same.

T

#### Terry Pinnell

Jan 1, 1970
0
Terry Pinnell said:
Those gates in Chris's circuit could be in a variety of ICs, and so
the pins will vary accordingly. For example, here's the circuit
redrawn for a CMOS 4011 Quad NAND:
http://www.terrypin.dial.pipex.com/Images/LatchingSwitch.gif

Note that the circuit uses only 3 of the 4 ('Quad') gates. The two
input pins of the unused gate are therefore shown wired to ground.

And I meant to add that the 4011's supply and ground pins (not usually
shown explicitly on schematics) are 14 and 7 respectively.

M

#### Mark Ashley

Jan 1, 1970
0
Hi John

Just to clear up any confusion - [email protected] is me, posting from

No the gates in my circuit diagram are supposed to be AND gates, and the Os
were connections. I have downloaded a trial copy of CircuitMaker and tested
your circuit design (the one with the NOR gates) and have had limited
success. Would you mind if I email you screenshots of the circuit so I can
more easily explain?

Thanks
Mark

W

Jan 1, 1970
0
C

#### Chris

Jan 1, 1970
0
Mark said:
One of the legs of each momentary switch is connected to a common ground,
which comes from a single point on the xbox pad, then daisy chains to each
switch. This includes the four switches for the joystick I think. The other
side of each switch then goes to its own point on the pad. I haven't
measured what is going across the switch when it is closed, but I can do
this if necessary.

Is that enough information? I can post more or a schematic if you need me
to.

I really appreciate all your help!

Thanks
Mark

Hi, Mark. Try this (view in fixed font or Notepad):

 (X = X-Box pullup resistor)
T
 ---
.---o o---X---------.
 | |
| T |
 | --- |
o---o o---X--------.| VCC
 | || 4078 +
| T || 8-input |
 | --- |'-o| OR(Pin 1)/ .-. VCC VCC
o---o o---X-------.| | NOR(Pin 13) | | + +
 | |'--o| | | | |
| T | | 220K'-' .--o---o--.
 | --- '---o|__ | | |
o---o o---X------. -|>=| 1 | | |
 | '----o|1 |------------|----o |
| T -|__| | | o---->A
 | --- .----o| | | 555 |
o---o o---X------' | o--o-o |
 | .---o| +| | | |
| T | | 10uF --- '-o |
 | --- |.--o| --- | |
o---o o---X-------'| | | '--o---o--'
 | |.-o| | | |
| T || === === ===
 | --- || GND GND GND
o---o o---X--------'|
 | |
| T |
 | --- |
o---o o---X---------'
 |
===
 GND



VCC VCC
 + +
| |
 | |
.-----------------------. - C|
 | | ^ C|
| | | C|
 | .--------. | | |
| | | | | |
 | | === | '---o
| .-----o------.GND | |
 | | S | | ___ |/
'----oD Q o--------|___|- -| TIP120
 | | | 10K | |>
| 1/2 4013 | | .-. |
 | | | | | |
A>---------o CLK | | 10K| | |
 VCC | | | '-' |
+ | | | | |
 | | | | | |
.-. | Q'o-----' === ===
 10K | | | | GND GND
| | | R |
 '-' '-----o------'
| |
 o-----------'
|
 .1uF ---
---
 |
===
 GND
created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de
From your description, all 8 switches switch a logic level voltage to
GND when they are pressed, and show a logic level high when they're not
pressed. First, you need to get a power supply voltage which is the
same voltage as the power supply of the logic circuit you're
interfacing (+/- 0.2V). Once you've done that, get a 4078 (8-input
OR/NOR), a 555, and a 4013 to do your job, along with the handful of
components shown.

Not so elegant, but it should do the job. The CD4078 has 8 inputs and
two outputs -- OR (pin 1) and NOR (pin 13). The OR will only go low
when all 8 inputs are low (what you want). That signal then triggers a
555, which is on for about 2 seconds (giving you your debounce) and
clocking a 4013 set up as a toggle F-F. The R/C at the reset input
ensures that the circuit will power up with the transistor off.

You should be able to put all this on a small perfboard, and you'll be
good to go with the Pretendo relay switch.

Good luck
Chris

C

#### Chris

Jan 1, 1970
0
Chris said:
Hi, Mark. Try this (view in fixed font or Notepad):

(X = X-Box pullup resistor)
 T
---
 .---o o---X---------.
| |
 | T |
| --- |
 o---o o---X--------.| VCC
| || 4078 +
 | T || 8-input |
| --- |'-o| OR(Pin 1)/ .-. VCC VCC
 o---o o---X-------.| | NOR(Pin 13) | | + +
| |'--o| | | | |
 | T | | 220K'-' .--o---o--.
| --- '---o|__ | | |
 o---o o---X------. -|>=| 1 | | |
| '----o|1 |------------|----o |
 | T -|__| | | o---->A
| --- .----o| | | 555 |
 o---o o---X------' | o--o-o |
| .---o| +| | | |
 | T | | 10uF --- '-o |
| --- |.--o| --- | |
 o---o o---X-------'| | | '--o---o--'
| |.-o| | | |
 | T || === === ===
| --- || GND GND GND
 o---o o---X--------'|
| |
 | T |
| --- |
 o---o o---X---------'
|
 ===
GND


 VCC VCC
+ +
 | |
| |
 .-----------------------. - C|
| | ^ C|
 | | | C|
| .--------. | | |
 | | | | | |
| | === | '---o
 | .-----o------.GND | |
| | S | | ___ |/
 '----oD Q o--------|___|- -| TIP120
| | | 10K | |>
 | 1/2 4013 | | .-. |
| | | | | |
 A>---------o CLK | | 10K| | |
VCC | | | '-' |
 + | | | | |
| | | | | |
 .-. | Q'o-----' === ===
10K | | | | GND GND
 | | | R |
'-' '-----o------'
 | |
o-----------'
 |
.1uF ---
 ---
|
 ===
GND
created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

GND when they are pressed, and show a logic level high when they're not
pressed. First, you need to get a power supply voltage which is the
same voltage as the power supply of the logic circuit you're
interfacing (+/- 0.2V). Once you've done that, get a 4078 (8-input
OR/NOR), a 555, and a 4013 to do your job, along with the handful of
components shown.

Not so elegant, but it should do the job. The CD4078 has 8 inputs and
two outputs -- OR (pin 1) and NOR (pin 13). The OR will only go low
when all 8 inputs are low (what you want). That signal then triggers a
555, which is on for about 2 seconds (giving you your debounce) and
clocking a 4013 set up as a toggle F-F. The R/C at the reset input
ensures that the circuit will power up with the transistor off.

You should be able to put all this on a small perfboard, and you'll be
good to go with the Pretendo relay switch.

Good luck
Chris

The drawing wasn't too clear on something -- It's important that the
CMOS IC be at the same voltage as the X-Box. That will probably mean
using a 7805 if the X-box has a 5V supply, and an LM317 if it's an
oddball voltage. You can use either of these as a post-regulator after

.-------------------> To Relay
| ____
12V | | |
o--o---|7805|---o------> To Logic
+| |____| |+
--- | ---
10uF --- | ---10uF
| | |
=== === ===
GND GND GND
created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

Either that or jsut decide to get a 4PDT telecom relay with a 5V coil
voltage.

If you can, find out the power supply voltage and get back to us. You
might get some more help or another, better idea.

Good luck
Chris

J

#### John Fields

Jan 1, 1970
0
Hi John

Just to clear up any confusion - [email protected] is me, posting from

No the gates in my circuit diagram are supposed to be AND gates, and the Os
were connections. I have downloaded a trial copy of CircuitMaker and tested
your circuit design (the one with the NOR gates) and have had limited
success. Would you mind if I email you screenshots of the circuit so I can
more easily explain?

---
I used ORs, since for the circuit to work properly the gates must be
ORs since what's being detected is the all-zeroes state. If you use
ANDs, then any switch pressed will cause the output to go low, which
will effect the toggle.

It would be better if you posted them to
alt.binaries.schematics.electronic. That way, everyone who's
following the thread can stay connected.

M

#### Mark Ashley

Jan 1, 1970
0
John Fields said:
I used ORs, since for the circuit to work properly the gates must be
ORs since what's being detected is the all-zeroes state. If you use
ANDs, then any switch pressed will cause the output to go low, which
will effect the toggle.

I don't understand that. I thought an OR gate would output when *any* of the
inputs were true. I have copied and pasted this truth table for an OR gate:

Input A Input B Output Q
0 0 0
0 1 1
1 0 1
1 1 1

Also, I though an AND gate would only output if *all* of the inputs were
true, as below:

Input A Input B Output Q
0 0 0
0 1 0
1 0 0
1 1 1

I am sure that you are correct in what you say, but I would like to
understand it better rather than just taking your word for it

It would be better if you posted them to
alt.binaries.schematics.electronic. That way, everyone who's
following the thread can stay connected.

I have posted them there, under the same heading as this thread.

Thanks again
Mark

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