Alternate parts
 

Hi guys,

Throw me a bone here.......
Although I only have my UK Foundation licence, I'm not quite a novice
when it comes to circuits. I worked for many years as an IT systems
engineer, can read a schematic, and understand what a circuit is
doing.
What is really starting to bug me is trying to locate a source of
information for alternative parts, especially transistors. I have
acumulated literally hundreds of parts, but I can guarantee that for
any given project I wont have the exact quoted part and will have to
order in a part costing pennies with handling and delivery in pounds.
Maddening to be sure.
Does anyone know of a site that gives a list of alternative or
equivalent parts? As an example, I have hundreds of 2N2222 transistors
but the requirement is for a single BC547 of which I have none. The
datasheets would suggest that the 2N2222 would do the job, but is it
always going to be a 'suck it and see'?

Any advice gratefully received.

Simon (MW3CUR)

I have
acumulated literally hundreds of parts, but I can guarantee that for
any given project I wont have the exact quoted part and will have to
order in a part costing pennies with handling and delivery in pounds.

==============================

The genuine amateur, indeed the professional in thoughtful moments, looks at
the parts pile and asks himself "now what can I make from that? "

Or he visits car-boot sales stalls and asks the same question.

A bird in hand is worth two in the bush.

A pound to a penny, after a tedius pencil and paper design and a prolonged
search, key parts will eventually be found to be not available from
anywhere. Or be too expensive. So change to another more satisfying design.

Inevitably, Economy Rules!
----
Reg, G4FGQ

I have
acumulated literally hundreds of parts, but I can guarantee that for
any given project I wont have the exact quoted part and will have to
order in a part costing pennies with handling and delivery in pounds.

==============================

The genuine amateur, indeed the professional in thoughtful moments, looks at
the parts pile and asks himself "now what can I make from that? "

Or he visits car-boot sales stalls and asks the same question.

A bird in hand is worth two in the bush.

A pound to a penny, after a tedius pencil and paper design and a prolonged
search, key parts will eventually be found to be not available from
anywhere. Or be too expensive. So change to another more satisfying design.

Inevitably, Economy Rules!
----
Reg, G4FGQ

Marshon wrote:
Does anyone know of a site that gives a list of alternative or
equivalent parts?

Not really... and if I did, I wouldn't trust it. They can't possibly
know what is important in your particular circuit.

When the same device is made by several different manufacturers, each
one may give it a slightly different label. The only worthwhile thing
that so-called "equivalents" lists do is help you recognise the root
number that they all share. Devices that share the same root number are
directly interchangeable in most cases - because they are intended to be
the same.

But devices with different numbers are usually intended to be different
devices.

Be literal-minded about this: a true substitute can only be another
device of exactly the same type. In all other cases, think of it as a
*different* device that does *some* of the same things... namely, the
things that you need in that particular circuit.


As an example, I have hundreds of 2N2222 transistors but the
requirement is for a single BC547 of which I have none. The datasheets
would suggest that the 2N2222 would do the job, but is it always going
to be a 'suck it and see'?

If you've actually compared datasheets, you've already done far more
than most people. Think about what a transistor needs to do in that
particular circuit, and trust your own judgement.


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)

Marshon wrote:
Does anyone know of a site that gives a list of alternative or
equivalent parts?

Not really... and if I did, I wouldn't trust it. They can't possibly
know what is important in your particular circuit.

When the same device is made by several different manufacturers, each
one may give it a slightly different label. The only worthwhile thing
that so-called "equivalents" lists do is help you recognise the root
number that they all share. Devices that share the same root number are
directly interchangeable in most cases - because they are intended to be
the same.

But devices with different numbers are usually intended to be different
devices.

Be literal-minded about this: a true substitute can only be another
device of exactly the same type. In all other cases, think of it as a
*different* device that does *some* of the same things... namely, the
things that you need in that particular circuit.


As an example, I have hundreds of 2N2222 transistors but the
requirement is for a single BC547 of which I have none. The datasheets
would suggest that the 2N2222 would do the job, but is it always going
to be a 'suck it and see'?

If you've actually compared datasheets, you've already done far more
than most people. Think about what a transistor needs to do in that
particular circuit, and trust your own judgement.


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)

I agree with Reg, since you hae so many you've nothing to lose except a
little time and perhaps some smoke. I do many genereiuc swaps and the only
thing that concerns me first is the polarity, size and power. If those are
close I try it. I think in this case you're in luck as the first Google hit
shows both transistors. Here it is:
http://www.electronics-ee.com/Electr...ransistors.htm

Its always frustated me why the UK had to use a different system for
numbering similar things. Perhaps it's for the same reason we drive on
opposite sides of the road, hi hi hi. Drving over there frustates me so
mcuh I don't even try anymore unless there's no other choice but I do pick
up UK numbered transistors whenver I see them at swap meets, just in case I
can use it. So far I've only found a couple!

Let us know how it works and have fun
73
Hank WD5JFRP
"Marshon" wrote in message
...
Hi guys,

Throw me a bone here.......
Although I only have my UK Foundation licence, I'm not quite a novice
when it comes to circuits. I worked for many years as an IT systems
engineer, can read a schematic, and understand what a circuit is
doing.
What is really starting to bug me is trying to locate a source of
information for alternative parts, especially transistors. I have
acumulated literally hundreds of parts, but I can guarantee that for
any given project I wont have the exact quoted part and will have to
order in a part costing pennies with handling and delivery in pounds.
Maddening to be sure.
Does anyone know of a site that gives a list of alternative or
equivalent parts? As an example, I have hundreds of 2N2222 transistors
but the requirement is for a single BC547 of which I have none. The
datasheets would suggest that the 2N2222 would do the job, but is it
always going to be a 'suck it and see'?

Any advice gratefully received.

Simon (MW3CUR)

I agree with Reg, since you hae so many you've nothing to lose except a
little time and perhaps some smoke. I do many genereiuc swaps and the only
thing that concerns me first is the polarity, size and power. If those are
close I try it. I think in this case you're in luck as the first Google hit
shows both transistors. Here it is:
http://www.electronics-ee.com/Electr...ransistors.htm

Its always frustated me why the UK had to use a different system for
numbering similar things. Perhaps it's for the same reason we drive on
opposite sides of the road, hi hi hi. Drving over there frustates me so
mcuh I don't even try anymore unless there's no other choice but I do pick
up UK numbered transistors whenver I see them at swap meets, just in case I
can use it. So far I've only found a couple!

Let us know how it works and have fun
73
Hank WD5JFRP
"Marshon" wrote in message
...
Hi guys,

Throw me a bone here.......
Although I only have my UK Foundation licence, I'm not quite a novice
when it comes to circuits. I worked for many years as an IT systems
engineer, can read a schematic, and understand what a circuit is
doing.
What is really starting to bug me is trying to locate a source of
information for alternative parts, especially transistors. I have
acumulated literally hundreds of parts, but I can guarantee that for
any given project I wont have the exact quoted part and will have to
order in a part costing pennies with handling and delivery in pounds.
Maddening to be sure.
Does anyone know of a site that gives a list of alternative or
equivalent parts? As an example, I have hundreds of 2N2222 transistors
but the requirement is for a single BC547 of which I have none. The
datasheets would suggest that the 2N2222 would do the job, but is it
always going to be a 'suck it and see'?

Any advice gratefully received.

Simon (MW3CUR)

Its always frustated me why the UK had to use a different system for
numbering similar things. Perhaps it's for the same reason we drive on
opposite sides of the road, hi hi hi. Drving over there frustates me so
mcuh I don't even try anymore unless there's no other choice but I do pick
up UK numbered transistors whenver I see them at swap meets, just in case
I
can use it. So far I've only found a couple!
=============================================
You probably mean European instead of UK numbering system versus the US
system.
And also there is of course the Nippon numbering system.
To my knowledge there are only few commonly used transistors with a typical
UK numbering code like the ZTX (Ferranti ?) series.


Frank GM0CSZ / KN6WH

Its always frustated me why the UK had to use a different system for
numbering similar things. Perhaps it's for the same reason we drive on
opposite sides of the road, hi hi hi. Drving over there frustates me so
mcuh I don't even try anymore unless there's no other choice but I do pick
up UK numbered transistors whenver I see them at swap meets, just in case
I
can use it. So far I've only found a couple!
=============================================
You probably mean European instead of UK numbering system versus the US
system.
And also there is of course the Nippon numbering system.
To my knowledge there are only few commonly used transistors with a typical
UK numbering code like the ZTX (Ferranti ?) series.


Frank GM0CSZ / KN6WH

"Marshon" wrote in message
...
Hi guys,

Throw me a bone here.......
....What is really starting to bug me is trying to locate a source of
information for alternative parts, especially transistors. I have
acumulated literally hundreds of parts, ...


'suck and see'
Sounds like a new Matel toy...

Simon,
You claim to be no dummy, so... You know what you have, so look at the
application and take what you have that fits the application the best, then
tweek away...er, uh, rather optimize for your choice. The 2N2222 will
probably work on 99% of the projects anyway....

I vote... start suckin'...

--
Steve N, K,9;d, c. i My email has no u's.