Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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Default UK source for this magnetic switch?

Can anyone point me towards a UK source (phone or online) for an
inexpensive cylindrical, enclosed reed switch, N/C, for use in a
burglar alarm circuit please.

I'm still googling but so far without success and want to place an
order for delivery Monday.

--
Terry, East Grinstead, UK
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Default UK source for this magnetic switch?

Aren't there any electronic-parts distributors in the UK that consumers can
purchase from?


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Default UK source for this magnetic switch?

William Sommerwerck wrote:
Aren't there any electronic-parts distributors in the UK that consumers can
purchase from?


"electronic-parts distributor" in the UK implies a trade only source
with limited interest in selling to retail customers. Those that do,
typically charge exorbitant delivery, minimun order and service charges
- leaving the only real alternative to be a toy shop called Maplin. Or eBay.

--
Adrian C
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Default UK source for this magnetic switch?

Terry wrote:
Can anyone point me towards a UK source (phone or online) for an
inexpensive cylindrical, enclosed reed switch, N/C, for use in a
burglar alarm circuit please.


William Sommerwerck wrote:
Aren't there any electronic-parts distributors in the UK that consumers can
purchase from?


Plenty, but he's looking for the wrong thing.

There is no such thing as a NC reed switch. The induced magnetism in the
reeds *always* attracts them together when you bring the magnet up, and
never repels them so all two terminal bare reed switches are NO.
It is possible to put an additional non-magnetic reed in the capsule, so
that one of the magnetic reeds is in contact with it until an external
magnetic field is applied, but as the reeds have to be brought out
through the pinch of the glass capsule to support them, this provides a
SPDT switch, not a NC one although it can be used as such.

If he googles 'SPDT reed switch' (without the quotes), both Rapid and
Maplin stock them. but for alarm use, I'm fairly sure he wants a
complete reed sensor and magnet pair for a NC loop, NOT a bare reed capsule.

If he's looking for a switch/magnet pair he can mount in the edge of a
door and its frame in drilled holes, googling 'recessed reed switch'
will find plenty, all NC in the presence of their magnet (i.e. with the
door closed). Again Maplin have some.

If he wants a true NC action, he's either going to have to stick a bare
SPDT reed in a cylindrical housing e.g a plastic tube from a biro with a
dab of hot glue or mess around with a biasing magnet to cancel out the
field of the actuating magnet as it approaches. Enclosed SPDT reed
switches, although nearly as rare as hens teeth, are available but
apparently not in a cylindrical recessed format.

--
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Default UK source for this magnetic switch?

On Sat, 07 Feb 2009 11:32:23 +0000, Terry Pinnell
wrote:

Can anyone point me towards a UK source (phone or online) for an
inexpensive cylindrical, enclosed reed switch, N/C, for use in a
burglar alarm circuit please.

I'm still googling but so far without success and want to place an
order for delivery Monday.


No Radio Shack there? Try an alarm company then... They were commonly
used in the big dish satellite systems on the positioning motor, but
since big dishes are uncommon now, that's not a good source, but some
satellite dish companies may have a few sitting on the shelf.


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Default UK source for this magnetic switch?


"Adrian C" wrote in message
...
William Sommerwerck wrote:
Aren't there any electronic-parts distributors in the UK that consumers
can
purchase from?


"electronic-parts distributor" in the UK implies a trade only source with
limited interest in selling to retail customers. Those that do, typically
charge exorbitant delivery, minimun order and service charges - leaving
the only real alternative to be a toy shop called Maplin. Or eBay.

--
Adrian C



Who could forget CPC/Farnell? Deal with them once and they'll keep your
letter box well fed for the rest of your life!

Excellent stock range though, miles bigger than Maplin.

Chris


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Default UK source for this magnetic switch?


"Ian Massive Pedant "
Terry wrote:

Can anyone point me towards a UK source (phone or online) for an
inexpensive cylindrical, enclosed reed switch, N/C, for use in a
burglar alarm circuit please.



There is no such thing as a NC reed switch.



** It's a better than even money bet Terry wants the switch to be closed
with a magnet nearby.

Which IS the NORMAL situation in an alarm installation.



...... Phil



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Default UK source for this magnetic switch?

christofire wrote:

Who could forget CPC/Farnell? Deal with them once and they'll keep your
letter box well fed for the rest of your life!


Yeah, but they are trade.

You can deal as an individual but on small quantities you pay postage,
don't get free technical support etc.. Basically 2nd class treatment and
they make you feel that. Attempts at getting trade registration for my
credit worthy limited company failed at Farnell without an explanation
why :-(

It takes a bit longer, but I find eBay works for me. If it's urgent,
then Maplin, Cricklewood Electronics or me turning up at an RS trade
counter with my VAT registration certificate (yes really).

BTW Radio Shack pulled out years ago. Now that was a toy shop...

--
Adrian C
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Default UK source for this magnetic switch?

In article ,
William Sommerwerck wrote:
Aren't there any electronic-parts distributors in the UK that consumers
can purchase from?


You don't even need an electronics distributor - electrical wholesalers
keep this sort of thing.

http://www.tlc-direct.co.uk/Main_Ind...ies/index.html

and will sell any value item with no surcharge in their branches. I've
never used them for mail order.

Most electronics distributors will have a minimum order - or high P&P for
a small value item.

Maplin (UK sort of RS) *may* have this sort of thing in some shops.

Or of course Ebay.

--
*Taxation WITH representation ain't much fun, either.

Dave Plowman London SW
To e-mail, change noise into sound.
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Default UK source for this magnetic switch?

Phil Allison wrote:
"Ian Massive Pedant "
Terry wrote:
Can anyone point me towards a UK source (phone or online) for an
inexpensive cylindrical, enclosed reed switch, N/C, for use in a
burglar alarm circuit please.


There is no such thing as a NC reed switch.



** It's a better than even money bet Terry wants the switch to be closed
with a magnet nearby.

Which IS the NORMAL situation in an alarm installation.



..... Phil


You snipped the bit where I gave a usable search term and suggestion for
a retail supplier for exactly that! Here, I've put it back:

for alarm use, I'm fairly sure he wants a complete reed sensor and
magnet pair for a NC loop, NOT a bare reed capsule.

If he's looking for a switch/magnet pair he can mount in the edge
of a door and its frame in drilled holes, googling 'recessed reed
switch' will find plenty, all NC in the presence of their magnet
(i.e. with the door closed). Again Maplin have some.


Thanks for not swearing ;-)

--
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ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
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"Adrian C" wrote in message
...
christofire wrote:

Who could forget CPC/Farnell? Deal with them once and they'll keep your
letter box well fed for the rest of your life!


Yeah, but they are trade.

You can deal as an individual but on small quantities you pay postage,
don't get free technical support etc.. Basically 2nd class treatment and
they make you feel that. Attempts at getting trade registration for my
credit worthy limited company failed at Farnell without an explanation why
:-(



I've never had a problem with CPC that wasn't resolved with an e-mail or
two. According to http://cpc.farnell.com/terms-and-conditions it's 'Small
Order Handling Charges', not postage, that they levy on orders smaller than
45 ex VAT. I guess this amounts to the same, but I don't think I've ever
needed to trouble them with less than 45 quids' worth.

Chris


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Default UK source for this magnetic switch?

On 2009-02-07, Adrian C wrote:
William Sommerwerck wrote:
Aren't there any electronic-parts distributors in the UK that consumers can
purchase from?


"electronic-parts distributor" in the UK implies a trade only source
with limited interest in selling to retail customers. Those that do,
typically charge exorbitant delivery, minimun order and service charges
- leaving the only real alternative to be a toy shop called Maplin. Or eBay.


Find one where you can walk in off the street during business hours
if you demonstrate posession of atleast half a clue when you walk in
and pay cash they'll treat you ok.



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Default UK source for this magnetic switch?

In article ,
Jasen Betts wrote:
"electronic-parts distributor" in the UK implies a trade only source
with limited interest in selling to retail customers. Those that do,
typically charge exorbitant delivery, minimun order and service
charges - leaving the only real alternative to be a toy shop called
Maplin. Or eBay.


Find one where you can walk in off the street during business hours
if you demonstrate posession of atleast half a clue when you walk in
and pay cash they'll treat you ok.


The only one in the UK which has trade counters in several cities is RS
Components - and they won't serve someone walking in off the street. And
rightly so - a genuine client shouldn't have to wait while an amateur asks
for advice, etc.

Maplin is the place for that sort of thing.

--
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Dave Plowman London SW
To e-mail, change noise into sound.
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Dave Plowman (News) wrote:

In article ,
Jasen Betts wrote:
"electronic-parts distributor" in the UK implies a trade only
source with limited interest in selling to retail customers. Those
that do, typically charge exorbitant delivery, minimun order and
service charges - leaving the only real alternative to be a toy
shop called Maplin. Or eBay.


Find one where you can walk in off the street during business hours
if you demonstrate posession of atleast half a clue when you walk in
and pay cash they'll treat you ok.


The only one in the UK which has trade counters in several cities is
RS Components - and they won't serve someone walking in off the
street. And rightly so - a genuine client shouldn't have to wait while
an amateur asks for advice, etc.

Maplin is the place for that sort of thing.


Actally B&Q, Focus, Wikkes, Aldi, Morrisons, Even Asda have or have had
similar devices on their shelves !

--
Best Regards:
Baron.
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Default UK source for this magnetic switch?

In article ,
Baron wrote:
Dave Plowman (News) wrote:


In article ,
Jasen Betts wrote:
"electronic-parts distributor" in the UK implies a trade only
source with limited interest in selling to retail customers. Those
that do, typically charge exorbitant delivery, minimun order and
service charges - leaving the only real alternative to be a toy
shop called Maplin. Or eBay.


Find one where you can walk in off the street during business hours
if you demonstrate posession of atleast half a clue when you walk in
and pay cash they'll treat you ok.


The only one in the UK which has trade counters in several cities is
RS Components - and they won't serve someone walking in off the
street. And rightly so - a genuine client shouldn't have to wait while
an amateur asks for advice, etc.

Maplin is the place for that sort of thing.


Actally B&Q, Focus, Wikkes, Aldi, Morrisons, Even Asda have or have had
similar devices on their shelves !


But not a N/C one. You'll need to obtain the correct reed switch elsewhere
and fit it to the housing. Or just use a transistor to invert the output
as I suggested earlier.

--
*When cheese gets it's picture taken, what does it say?

Dave Plowman London SW
To e-mail, change noise into sound.


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Default UK source for this magnetic switch?

Dave Plowman (News) wrote:

In article ,
Baron wrote:
Dave Plowman (News) wrote:


In article ,
Jasen Betts wrote:
"electronic-parts distributor" in the UK implies a trade only
source with limited interest in selling to retail customers.
Those that do, typically charge exorbitant delivery, minimun
order and service charges - leaving the only real alternative to
be a toy shop called Maplin. Or eBay.

Find one where you can walk in off the street during business
hours if you demonstrate posession of atleast half a clue when you
walk in and pay cash they'll treat you ok.

The only one in the UK which has trade counters in several cities
is RS Components - and they won't serve someone walking in off the
street. And rightly so - a genuine client shouldn't have to wait
while an amateur asks for advice, etc.

Maplin is the place for that sort of thing.


Actally B&Q, Focus, Wikkes, Aldi, Morrisons, Even Asda have or have
had similar devices on their shelves !


But not a N/C one. You'll need to obtain the correct reed switch
elsewhere and fit it to the housing. Or just use a transistor to
invert the output as I suggested earlier.


All the ones I referred to were standard reeds with an actuating magnet
in a separate housing. Ak for burglar alarm systems.
I've never seen a normally closed one used for those, although I have
seen change over, SPCO, reeds used in electronic equipment.

--
Best Regards:
Baron.
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Default UK source for this magnetic switch?

In article , Dave Plowman (News)
wrote:
The only one in the UK which has trade counters in several cities is RS
Components - and they won't serve someone walking in off the street. And
rightly so - a genuine client shouldn't have to wait while an amateur
asks for advice, etc.


CPC have counters and served me, but i have registered an account on their
web site . It was No problem and the parts were waiting for pick up.

--
Terminal_Crazy

Mitch - 1995 Z28 LT1 M6
Lancashire England
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Default UK source for this magnetic switch?

Terminal Crazy wrote:
In article , Dave Plowman (News)
wrote:
The only one in the UK which has trade counters in several cities is RS
Components - and they won't serve someone walking in off the street. And
rightly so - a genuine client shouldn't have to wait while an amateur
asks for advice, etc.


CPC have counters and served me, but i have registered an account on their
web site . It was No problem and the parts were waiting for pick up.

I buy from CPC weekly, my orders generally are for more than the minumum
carriage free amount, 45 IIRC, but I think it`s only a few pounds for
standard delivery.

As far as CPC being trade only. that`s a laugh, it was a big bone of
contention a few years ago when they started putting their weekly
special offer leaflets in punter magazines and opened a 'trade counter'
that is open to all. I`ve dealt with CPC since the early 80`s, they are
a good company, I`ve had very few problems, and complains are dealt with
asap.

Farnell also will hapily sell to the public via their website - The
Farnell organisation own CPC btw, I`ve also had good dealings with Rapid
Online.


Ron


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Ron wrote:

Farnell also will hapily sell to the public via their website - The
Farnell organisation own CPC btw, I`ve also had good dealings with Rapid
Online.


Happily, that's a laugh.. :-(

The word is grudgingly. Both CPC and Farnell technical support is free
for account holders, and there is no minimum order for trade customers.
Other companies even have free post for trade customers on any order
size. Because on things like internet sales they have to agree to
"distance selling regulations" and similar, they end up losing money
dealing with consumers. Maplin is the only UK national choice for
hobbyists and small time repairers like me.

Never mind, if it works for you. Good :-)

eBay and purchasing outside the UK works for me and yes; I know what a
scam fest eBay can sometimes be, but not in this case.

For example I recently had to replace a shot schottky SMD diode in a HP
printer SMPS. Per part, 20p each from Farnell. Minimun order charge 20.
Post and packing 4.25.

From an eBay seller in the states, 8 including postage for 500 diodes.
They were delivered within the week.

If it's urgent I jump in the car and find something in a shop closer. Or
risk a dodgy substitute for the part, which I really shouldn't do if
it's critical ....

--
Adrian C
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Default UK source for this magnetic switch?

In article ,
Terminal Crazy wrote:
In article , Dave Plowman (News)
wrote:
The only one in the UK which has trade counters in several cities is
RS Components - and they won't serve someone walking in off the
street. And rightly so - a genuine client shouldn't have to wait while
an amateur asks for advice, etc.


CPC have counters and served me, but i have registered an account on
their web site . It was No problem and the parts were waiting for pick
up.


I understood CPC have only the one trade counter - unlike RS Components
who have some 15 in various parts of the country.

--
*Atheism is a non-prophet organization.

Dave Plowman London SW
To e-mail, change noise into sound.


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Default UK source for this magnetic switch?


"Terry Pinnell" wrote in message
...
Can anyone point me towards a UK source (phone or online) for an
inexpensive cylindrical, enclosed reed switch, N/C, for use in a
burglar alarm circuit please.

I'm still googling but so far without success and want to place an
order for delivery Monday.

--
Terry, East Grinstead, UK


Dragging this discussion back from the trading pinciples of some companies.

I do not know about the UK but in Australia and I suspect the USA this sort
of thing is easy to find at DIY stores like Bunnings (here) or Home
Depot/Lowes (in the US) in the build your self a burgular alarm aisle.

There are at least three layman's electronic suppliers in Aus, DSE (about
equiv to Radio Shack), Jaycar (a bit better) and Altronics. All have walk
in, chose for yourself, super market type shops. Surley the UK has
equivelents.

John G.


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Default UK source for this magnetic switch?

John G. wrote:
"Terry Pinnell" wrote in message
...
Can anyone point me towards a UK source (phone or online) for an
inexpensive cylindrical, enclosed reed switch, N/C, for use in a
burglar alarm circuit please.

I'm still googling but so far without success and want to place an
order for delivery Monday.

--
Terry, East Grinstead, UK


Dragging this discussion back from the trading pinciples of some companies.

I do not know about the UK but in Australia and I suspect the USA this sort
of thing is easy to find at DIY stores like Bunnings (here) or Home
Depot/Lowes (in the US) in the build your self a burgular alarm aisle.

There are at least three layman's electronic suppliers in Aus, DSE (about
equiv to Radio Shack), Jaycar (a bit better) and Altronics. All have walk
in, chose for yourself, super market type shops. Surley the UK has
equivelents.

John G.


Unfortunately Maplin have nearly turned into Rat Shack. No blister
packed resistors at three for a pound (80's pricing, it would be 3 for
five pounds now) but they've got the piles of consumer tat and now have
branches without a parts counter. Where they still do parts, their
standard stock level for any store stocked semiconductor (and that's not
many from their vastly reduced range) is 3 with long restocking
intervals. Bit awkward if you are assembling a bridge from discrete
diodes or want enough bicolour LEDs to monitor a bi-directional serial
link with handshake lines. They are better than nothing but not by a
lot. I am not aware of any other chain of retail electronic component
stockists, but hopefully someone knows of some alternatives.

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
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In article ,
IanM wrote:
I am not aware of any other chain of retail electronic component
stockists, but hopefully someone knows of some alternatives.


Rapid Electronics have the best terms for small value mail order and post
pretty quickly. next day for most things. One shop I know of in London -
but haven't used - is Cricklewood Electronics.

http://www.cricklewoodelectronics.co...ewood/home.php

--
*Why does the sun lighten our hair, but darken our skin?

Dave Plowman London SW
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Default UK source for this magnetic switch?

On 2/7/2009 3:32 AM Terry Pinnell spake thus:

Can anyone point me towards a UK source (phone or online) for an
inexpensive cylindrical, enclosed reed switch, N/C, for use in a
burglar alarm circuit please.

I'm still googling but so far without success and want to place an
order for delivery Monday.


Sorry, I can't help, being in the US where things like this are
trivially easy to get.

Just one thing: did someone here say that switches like this were
typically N/O rather than N/C? And that such could be used for an alarm
circuit?

Think about it: if you have a N/O switch as an alarm sensor, all the bad
guy has to do to get in is to cut it out of the circuit. There's a
reason alarm switches are normally closed.

Hard to believe a N/C reed switch wouldn't be easy to buy somewhere in
England.


--
Personally, I like Vista, but I probably won't use it. I like it
because it generates considerable business for me in consulting and
upgrades. As long as there is hardware and software out there that
doesn't work, I stay in business. Incidentally, my company motto is
"If this stuff worked, you wouldn't need me".

- lifted from sci.electronics.repair
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Default UK source for this magnetic switch?


"David Nebenzahl" wrote in message
.com...
On 2/7/2009 3:32 AM Terry Pinnell spake thus:

Can anyone point me towards a UK source (phone or online) for an
inexpensive cylindrical, enclosed reed switch, N/C, for use in a
burglar alarm circuit please.

I'm still googling but so far without success and want to place an
order for delivery Monday.


Sorry, I can't help, being in the US where things like this are trivially
easy to get.

Just one thing: did someone here say that switches like this were
typically N/O rather than N/C? And that such could be used for an alarm
circuit?

Think about it: if you have a N/O switch as an alarm sensor, all the bad
guy has to do to get in is to cut it out of the circuit. There's a reason
alarm switches are normally closed.

Hard to believe a N/C reed switch wouldn't be easy to buy somewhere in
England.


N/O reed switches are the simlest to build and in alarm systems are useually
held closed by a magnet on the other side of the door etc. so it will
activate the alarm if the door opens or the wire is cut.
But like you I find it hard to believe they are hard to get.

Terry, If you only need one I will post it from Australia if you are
desperate.

John G.




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Default UK source for this magnetic switch?

On Sun, 08 Feb 2009 20:01:18 -0800, David Nebenzahl wrote:

Just one thing: did someone here say that switches like this were
typically N/O rather than N/C? And that such could be used for an alarm
circuit?

Think about it: if you have a N/O switch as an alarm sensor, all the bad
guy has to do to get in is to cut it out of the circuit. There's a
reason alarm switches are normally closed.


Phil Allison said:

** It's a better than even money bet Terry wants the switch to be closed
with a magnet nearby.

Which IS the NORMAL situation in an alarm installation.


IOW, it's a question of how you define "normally".

Reed switches are open in the absence of a magnetic field, and closed when
one is present.

For a relay, you would call such contacts "normally open".

But for a burglar alarm, the "normal" situation is for the magnetic field
to be present, from a permanent magnet in a door or window which is
"normally" adjacent to the reed switch. In this situation, the contacts
will be held closed.


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Default UK source for this magnetic switch?

On 2/8/2009 10:11 PM Nobody spake thus:

On Sun, 08 Feb 2009 20:01:18 -0800, David Nebenzahl wrote:

Just one thing: did someone here say that switches like this were
typically N/O rather than N/C? And that such could be used for an alarm
circuit?

Think about it: if you have a N/O switch as an alarm sensor, all the bad
guy has to do to get in is to cut it out of the circuit. There's a
reason alarm switches are normally closed.


Phil Allison said:

** It's a better than even money bet Terry wants the switch to be closed
with a magnet nearby.

Which IS the NORMAL situation in an alarm installation.


IOW, it's a question of how you define "normally".

Reed switches are open in the absence of a magnetic field, and closed when
one is present.

For a relay, you would call such contacts "normally open".

But for a burglar alarm, the "normal" situation is for the magnetic field
to be present, from a permanent magnet in a door or window which is
"normally" adjacent to the reed switch. In this situation, the contacts
will be held closed.


Ah, so. That makes sense.


--
Personally, I like Vista, but I probably won't use it. I like it
because it generates considerable business for me in consulting and
upgrades. As long as there is hardware and software out there that
doesn't work, I stay in business. Incidentally, my company motto is
"If this stuff worked, you wouldn't need me".

- lifted from sci.electronics.repair
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Default UK source for this magnetic switch?

Try this link.
Of course you would have to wait for Her Majesty's Mail but here is all the
info you should need.
http://www.altronics.com.au/index.as...ubmit= SEARCH

John G.


"Terry Pinnell" wrote in message
...
Can anyone point me towards a UK source (phone or online) for an
inexpensive cylindrical, enclosed reed switch, N/C, for use in a
burglar alarm circuit please.

I'm still googling but so far without success and want to place an
order for delivery Monday.

--
Terry, East Grinstead, UK



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Default UK source for this magnetic switch?

On Sun, 08 Feb 2009 20:01:18 -0800, David Nebenzahl
wrote:

:On 2/7/2009 3:32 AM Terry Pinnell spake thus:
:
: Can anyone point me towards a UK source (phone or online) for an
: inexpensive cylindrical, enclosed reed switch, N/C, for use in a
: burglar alarm circuit please.
:
: I'm still googling but so far without success and want to place an
: order for delivery Monday.
:
:Sorry, I can't help, being in the US where things like this are
:trivially easy to get.

Have you been wondering why the OP has not bothered to respond to any of the
responses?

I would bet my last cent that he is a troll and many have been drawn to the
apparently innocent "come in sucker" question. Nobody is so dumb that he doesn't
know that such devices are readily available from any number of electronics
parts outlets. They are just as trivially easy to get in the UK as in the US.
For example, Maplin is well known to all electronics hobbyists...
http://www.maplin.co.uk/Module.aspx?...eed%20Swi tch
and many others carry similar items.


:
:Just one thing: did someone here say that switches like this were
:typically N/O rather than N/C? And that such could be used for an alarm
:circuit?
:
:Think about it: if you have a N/O switch as an alarm sensor, all the bad
:guy has to do to get in is to cut it out of the circuit. There's a
:reason alarm switches are normally closed.
:
:Hard to believe a N/C reed switch wouldn't be easy to buy somewhere in
:England.
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Default UK source for this magnetic switch?




"Terry Pinnell" wrote in message
...
Can anyone point me towards a UK source (phone or online) for an
inexpensive cylindrical, enclosed reed switch, N/C, for use in a
burglar alarm circuit please.

I'm still googling but so far without success and want to place an
order for delivery Monday.


**Farnell.


--
Trevor Wilson
www.rageaudio.com.au




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Default UK source for this magnetic switch?

On 2/9/2009 12:59 AM Ross Herbert spake thus:

Have you been wondering why the OP has not bothered to respond to any
of the responses?


Busy? Distracted? Forgot about it?

I would bet my last cent that he is a troll and many have been drawn
to the apparently innocent "come in sucker" question. Nobody is so
dumb that he doesn't know that such devices are readily available
from any number of electronics parts outlets. They are just as
trivially easy to get in the UK as in the US.


Pretty polite and straightforward for a troll, if you ask me.

And maybe not dumb but ignorant instead. (One reason people ask
questions in the first place.)


--
Personally, I like Vista, but I probably won't use it. I like it
because it generates considerable business for me in consulting and
upgrades. As long as there is hardware and software out there that
doesn't work, I stay in business. Incidentally, my company motto is
"If this stuff worked, you wouldn't need me".

- lifted from sci.electronics.repair
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Default UK source for this magnetic switch?

On Mon, 09 Feb 2009 08:59:21 GMT, Ross Herbert
wrote:

On Sun, 08 Feb 2009 20:01:18 -0800, David Nebenzahl
wrote:

:On 2/7/2009 3:32 AM Terry Pinnell spake thus:
:
: Can anyone point me towards a UK source (phone or online) for an
: inexpensive cylindrical, enclosed reed switch, N/C, for use in a
: burglar alarm circuit please.
:
: I'm still googling but so far without success and want to place an
: order for delivery Monday.
:
:Sorry, I can't help, being in the US where things like this are
:trivially easy to get.

Have you been wondering why the OP has not bothered to respond to any of the
responses?

I would bet my last cent that he is a troll and many have been drawn to the
apparently innocent "come in sucker" question.


---
And you'd lose.

Terry hasn't been around for a while, but when he was a regular his
posts were always interesting and his demeanor always polite.
---

Nobody is so dumb that he doesn't
know that such devices are readily available from any number of electronics
parts outlets.


---
It's not so much about being dumb as it is about not knowing something
and asking for help.
---

They are just as trivially easy to get in the UK as in the US.
For example, Maplin is well known to all electronics hobbyists...
http://www.maplin.co.uk/Module.aspx?...eed%20Swi tch
and many others carry similar items.


---
So, instead of just posting the link, (which would have been helpful)
you accompany it with a slap, which does nothing but start trouble.

**** you.

JF
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Default UK source for this magnetic switch?

On Mon, 09 Feb 2009 14:44:52 -0600, John Fields
wrote:

:On Mon, 09 Feb 2009 08:59:21 GMT, Ross Herbert
:wrote:
:
:On Sun, 08 Feb 2009 20:01:18 -0800, David Nebenzahl
:wrote:
:
::On 2/7/2009 3:32 AM Terry Pinnell spake thus:
::
:: Can anyone point me towards a UK source (phone or online) for an
:: inexpensive cylindrical, enclosed reed switch, N/C, for use in a
:: burglar alarm circuit please.
::
:: I'm still googling but so far without success and want to place an
:: order for delivery Monday.
::
::Sorry, I can't help, being in the US where things like this are
::trivially easy to get.
:
:Have you been wondering why the OP has not bothered to respond to any of the
:responses?
:
:I would bet my last cent that he is a troll and many have been drawn to the
:apparently innocent "come in sucker" question.
:
:---
:And you'd lose.

I'm not so sure about that. While there are many replies from others there is
not one which points to a supply source. So where is there a response from him
to indicate he requires further clarification or assistance? To request help and
then not respond is just plain rude in my book. Even something letting people
know he was interested in their answers would be nice.

:
:Terry hasn't been around for a while, but when he was a regular his
osts were always interesting and his demeanor always polite.

Unlike yourself as we can see from your final epithet in this response of yours.

:---
:
: Nobody is so dumb that he doesn't
:know that such devices are readily available from any number of electronics
:parts outlets.
:
:---
:It's not so much about being dumb as it is about not knowing something
:and asking for help.

The term "dumb" was meant to convey "ignorance". And ignorance in this case as
to how to find the part he was looking for. He states in his request that he
knows the part is used in burglar alarms and that it is a reed switch which can
be operated by a magnet. Now anybody with a modicum of intelligence in using
Google can combine 2 of these facts into a search term. For example;
burglar+alarm+reed+switch. And if he was aware of Google's ability to search
within a locale he would add uk at the end to get results for his country. To be
completely correct for a locale search the term would be site:.uk

:---
:
:They are just as trivially easy to get in the UK as in the US.
:For example, Maplin is well known to all electronics hobbyists...
:http://www.maplin.co.uk/Module.aspx?...eed%20Swi tch
:and many others carry similar items.
:
:---
:So, instead of just posting the link, (which would have been helpful)
:you accompany it with a slap, which does nothing but start trouble.
:
:**** you.
:
:JF

John, you have just compounded the situation with your gratuitous and uncalled
for FU compliment.

I was not intending to deliver a slap along with the helpful link, but simply to
prompt the OP to respond in some manner. You took that responsibility for
yourself instead of letting him do so.

If the OP has been following the thread which he started in the hope of getting
help (why would he have posted if not to follow and read answers?) then why has
he not responded with some sort of indication that he requires further
clarification or that he welcomes the suggestions? That is tantamount to
"trolling" in my opinion.
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Default UK source for this magnetic switch?

On Feb 7, 11:32*am, Terry Pinnell
wrote:
Can anyone point me towards a UK source (phone or online) for an
inexpensive cylindrical, enclosed reed switch, N/C, for use in a
burglar alarm circuit please.

I'm still googling but so far without success and want to place an
order for delivery Monday.

--
Terry, East Grinstead, UK


If you are still having problems contact me.
regards
Ed
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Default UK source for this magnetic switch?

Nobody wrote:

On Sun, 08 Feb 2009 20:01:18 -0800, David Nebenzahl wrote:

Just one thing: did someone here say that switches like this were
typically N/O rather than N/C? And that such could be used for an alarm
circuit?

Think about it: if you have a N/O switch as an alarm sensor, all the bad
guy has to do to get in is to cut it out of the circuit. There's a
reason alarm switches are normally closed.


Phil Allison said:

** It's a better than even money bet Terry wants the switch to be closed
with a magnet nearby.

Which IS the NORMAL situation in an alarm installation.


IOW, it's a question of how you define "normally".

Reed switches are open in the absence of a magnetic field, and closed when
one is present.

For a relay, you would call such contacts "normally open".

But for a burglar alarm, the "normal" situation is for the magnetic field
to be present, from a permanent magnet in a door or window which is
"normally" adjacent to the reed switch. In this situation, the contacts
will be held closed.


Thanks for the responses and my apologies for not responding sooner.

Yes, as many have pointed out, I was mistaken about the N/C
requirement. It was indeed the ambiguity over the meaning of 'normally
open' that caused my mistake. I'd forgotten that the accompanying
magnet normally(!) kept it closed. IOW I was regarding 'normality' as
the state when my doors are closed, not when the potential burglar was
gaining access ;-)

I did realise my mistake soon after posting and duly ordered a few
from Rapid Electronics
http://www.rapidonline.com/Electroni...354/kw/78-0797


--
Terry, East Grinstead, UK


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Default UK source for this magnetic switch?

On Tue, 10 Feb 2009 05:58:52 GMT, Ross Herbert
wrote:

On Mon, 09 Feb 2009 14:44:52 -0600, John Fields
wrote:

:On Mon, 09 Feb 2009 08:59:21 GMT, Ross Herbert
:wrote:
:
:On Sun, 08 Feb 2009 20:01:18 -0800, David Nebenzahl
:wrote:
:
::On 2/7/2009 3:32 AM Terry Pinnell spake thus:
::
:: Can anyone point me towards a UK source (phone or online) for an
:: inexpensive cylindrical, enclosed reed switch, N/C, for use in a
:: burglar alarm circuit please.
::
:: I'm still googling but so far without success and want to place an
:: order for delivery Monday.
::
::Sorry, I can't help, being in the US where things like this are
::trivially easy to get.
:
:Have you been wondering why the OP has not bothered to respond to any of the
:responses?
:
:I would bet my last cent that he is a troll and many have been drawn to the
:apparently innocent "come in sucker" question.
:
:---
:And you'd lose.
:---


I'm not so sure about that. While there are many replies from others there is
not one which points to a supply source.


---
???

There are several.
---

So where is there a response from him
to indicate he requires further clarification or assistance?




To request help and
then not respond is just plain rude in my book. Even something letting people
know he was interested in their answers would be nice.


---
So now you're setting yourself up as the arbiter of what a proper time
for response is?
---

:Terry hasn't been around for a while, but when he was a regular his
osts were always interesting and his demeanor always polite.

Unlike yourself as we can see from your final epithet in this response of yours.


---
I'm seldom polite when I'm dealing with assholes, but we're not talking
about me, we're talking about whether Terry's a troll or not, and you,
with your formidable 21 post history in this group have taken it upon
yourself to start unwarranted namecalling? As I said before, **** you.
---

: Nobody is so dumb that he doesn't
:know that such devices are readily available from any number of electronics
:parts outlets.
:
:---
:It's not so much about being dumb as it is about not knowing something
:and asking for help.

The term "dumb" was meant to convey "ignorance".


---
You're a liar. It was intended to be an insult.
---

And ignorance in this case as
to how to find the part he was looking for. He states in his request that he
knows the part is used in burglar alarms and that it is a reed switch which can
be operated by a magnet. Now anybody with a modicum of intelligence in using
Google can combine 2 of these facts into a search term. For example;
burglar+alarm+reed+switch. And if he was aware of Google's ability to search
within a locale he would add uk at the end to get results for his country. To be
completely correct for a locale search the term would be site:.uk


---
What you're missing is that he was Googling for magnetically unbiased
_normally closed_ reed switches,(which are as rare as hen's teeth) and
that he was apprised of that and what to search for.
---

:They are just as trivially easy to get in the UK as in the US.
:For example, Maplin is well known to all electronics hobbyists...
:http://www.maplin.co.uk/Module.aspx?...eed%20Swi tch
:and many others carry similar items.
:
:---
:So, instead of just posting the link, (which would have been helpful)
:you accompany it with a slap, which does nothing but start trouble.
:
:**** you.
:
:JF

John, you have just compounded the situation with your gratuitous and uncalled
for FU compliment.


---
IMO, it wasn't gratuitous, it was well deserved.
---

I was not intending to deliver a slap along with the helpful link, but simply to
prompt the OP to respond in some manner. You took that responsibility for
yourself instead of letting him do so.


---
No, I decided to insult you because of the heavy-handed way you decided
to treat someone you knew nothing about.
---

If the OP has been following the thread which he started in the hope of getting
help (why would he have posted if not to follow and read answers?) then why has
he not responded with some sort of indication that he requires further
clarification or that he welcomes the suggestions?


---
Perhaps because he'd been unable to?
---

That is tantamount to "trolling" in my opinion.


---
You've got a lot to learn, newbie.

JF
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Default UK source for this magnetic switch?

sirkituk wrote:

On Feb 7, 11:32*am, Terry Pinnell
wrote:
Can anyone point me towards a UK source (phone or online) for an
inexpensive cylindrical, enclosed reed switch, N/C, for use in a
burglar alarm circuit please.

I'm still googling but so far without success and want to place an
order for delivery Monday.

--
Terry, East Grinstead, UK


If you are still having problems contact me.
regards
Ed


Thanks Ed, sorted thanks. (See my post of a few hours ago.)

--
Terry, East Grinstead, UK


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