Transistor substitution

[Ivan Vegvary]

Want to breadboard small circuits from mid 1960's magazine articles.
Where on the web can I find today's equivalents for the specified transistors and diodes?
Just starting to learn solid state stuff.
Thanks!
Ivan Vegvary

 

[George Herold]

On Thursday, September 4, 2014 10:24:24 AM UTC-4, Ivan Vegvary wrote:

Want to breadboard small circuits from mid 1960's magazine articles.

Where on the web can I find today's equivalents for the specified transistors and diodes?

Just starting to learn solid state stuff.

Thanks!

Ivan Vegvary

If you posted a link or a picture of the circuit with part numbers. Someone here may be able to give you advice on replacements.

George H.

 

[JW]

On Thu, 4 Sep 2014 07:24:24 -0700 (PDT) Ivan Vegvary
<ivanvegvary@gmail.com> wrote in Message id:
<0d73ebdb-7b57-4894-acac-3fdd6a44d400@googlegroups.com>:

Want to breadboard small circuits from mid 1960's magazine articles.
Where on the web can I find today's equivalents for the specified transistors and diodes?
Just starting to learn solid state stuff.
Thanks!
Ivan Vegvary

You could start here:

http://nte01.nteinc.com/nte/NTExRefSemiProd.nsf/$$Search?OpenForm

http://www.allxref.com/

http://101science.com/transistor.htm#crossdb

http://www.ee.usyd.edu.au/tutorials/ee_database/electronic/cross.html

 

[Ivan Vegvary]

On Thursday, September 4, 2014 7:30:39 AM UTC-7, JW wrote:

On Thu, 4 Sep 2014 07:24:24 -0700 (PDT) Ivan Vegvary







Want to breadboard small circuits from mid 1960's magazine articles.

Where on the web can I find today's equivalents for the specified transistors and diodes?

Just starting to learn solid state stuff.

Thanks!

Ivan Vegvary



You could start here:



http://nte01.nteinc.com/nte/NTExRefSemiProd.nsf/$$Search?OpenForm



http://www.allxref.com/



http://101science.com/transistor.htm#crossdb



http://www.ee.usyd.edu.au/tutorials/ee_database/electronic/cross.html

Thanks for the links, JW, that really helps.

 

[Ivan Vegvary]

On Thursday, September 4, 2014 7:52:07 AM UTC-7, Michael Black wrote:

On Thu, 4 Sep 2014, Ivan Vegvary wrote:



Want to breadboard small circuits from mid 1960's magazine articles.

Where on the web can I find today's equivalents for the specified transistors and diodes?

Just starting to learn solid state stuff.

Thanks!

Ivan Vegvary



One thing to watch for with old circuits is whether they use germanium

transistors. Those aren't so common anymore, there was mostly a

switchover to silicon transistors. And the biasing requirements are

different for germanium transistors. If nothing else, they will work

at a lower voltage than bipolars generaly do.



Another thing to watch is whether the devices are NPN or PNP. That can

be adapted toa certain extent, but it defines whether the base and

collector voltages are positive (NPN), or negative (PNP). Though in the

early days, that may not immediately be obvious, since the circuit might

instead have ground as positive (rather than the more common ground as

negative), so they could ground the collector even though it is an NPN

transistor.



Another consideration is that while some stages can be quite fussy

in regard to parts substitution, lots of other stages aren't. Indeed,

magazines tended to use the same types of transistors. It was never clear

who or how someone picked a given device, but once it was out there,

others would use them too. And those devices were easier to get through

hobby channels, precisely because they were being used. So you'd see a

lot of 2N706s in the sixties, while later 2N2222s and 2N3906s. IN some

cases, people may not have even built with the specified device, just some

general type they had handy, then they list a common part so others can

easily get that part.





The first few projects I tried never worked. I'd copy out the list of

parts from the magazine, go to the store, and they'd make substitutions

that might not have been right or had some different pinout that I didn't

know about. Who knows, lots of variables at the beginning. But the

projects that first worked were when I learned enough about the parts so I

coudl reuse things I'd taken off circuit boards. So I was using generic

parts, but knowing enough to know what might work and what might not. You

cant' just make substitution, but once you have some background, it's

easier to see what can be changed and what can't be.



Since I was generally stripping junk equipment and reusing the parts, I

early on got a replacement guide for one of the Big Replacement Lines.

These were a smaller set of parts that could be carried by stores, and

then the substitution guide would lead you to a part that was kind of

close.



I never bought the expensive replacement line parts, I just used it to

look up transistors in a circuit, and then look up trnasistors I had, and

then I'd find matches to the common replacement, or look up the specs of

the replacement and see if I was "close enough". Since many circuits were

just using transistors they had, "being close" was often good enough, so

long as I knew enough that that VHF circuit would need better transistors

than that audio amplifier, and so on.



It seems daunting going in, but it didn't take that long when I was a kid,

reading as much as I could get my hands on.



Michael

Michael, I find your comments extremely helpful! Thanks you

 

[Ivan Vegvary]

On Thursday, September 4, 2014 9:33:10 AM UTC-7, Tim Wescott wrote:

On Thu, 04 Sep 2014 07:24:24 -0700, Ivan Vegvary wrote:



Want to breadboard small circuits from mid 1960's magazine articles.

Where on the web can I find today's equivalents for the specified

transistors and diodes?

Just starting to learn solid state stuff.

Thanks!

Ivan Vegvary



I'd start by looking to the hobby/surplus places for components -- for

silicon transistors, you may just find exactly what you want, instead of

equivalents.



All Electronics

MPJA Electronics

Jameco Electronics

Search on "surplus"



For germanium transistors, look on da bay -- I'm sure there are parts out

there.



For resistors and caps, for the most part, anything with the right value

will work.



And, as has been said -- if you're having trouble you can scan the

schematic, post it on some image-sharing site, then ask questions with a

link to the schematic and we'll help you out.



--



Tim Wescott

Wescott Design Services

http://www.wescottdesign.com

Tim, I think I remember from your previous posts that you are from Oregon. I live up in Sandy, OR. California transplant as of 11 years ago.
Thanks for your help.

 

[Michael Black]

On Thu, 4 Sep 2014, Ivan Vegvary wrote:

Want to breadboard small circuits from mid 1960's magazine articles.
Where on the web can I find today's equivalents for the specified transistors and diodes?
Just starting to learn solid state stuff.
Thanks!
Ivan Vegvary

One thing to watch for with old circuits is whether they use germanium
transistors. Those aren't so common anymore, there was mostly a
switchover to silicon transistors. And the biasing requirements are
different for germanium transistors. If nothing else, they will work
at a lower voltage than bipolars generaly do.

Another thing to watch is whether the devices are NPN or PNP. That can
be adapted toa certain extent, but it defines whether the base and
collector voltages are positive (NPN), or negative (PNP). Though in the
early days, that may not immediately be obvious, since the circuit might
instead have ground as positive (rather than the more common ground as
negative), so they could ground the collector even though it is an NPN
transistor.

Another consideration is that while some stages can be quite fussy
in regard to parts substitution, lots of other stages aren't. Indeed,
magazines tended to use the same types of transistors. It was never clear
who or how someone picked a given device, but once it was out there,
others would use them too. And those devices were easier to get through
hobby channels, precisely because they were being used. So you'd see a
lot of 2N706s in the sixties, while later 2N2222s and 2N3906s. IN some
cases, people may not have even built with the specified device, just some
general type they had handy, then they list a common part so others can
easily get that part.


The first few projects I tried never worked. I'd copy out the list of
parts from the magazine, go to the store, and they'd make substitutions
that might not have been right or had some different pinout that I didn't
know about. Who knows, lots of variables at the beginning. But the
projects that first worked were when I learned enough about the parts so I
coudl reuse things I'd taken off circuit boards. So I was using generic
parts, but knowing enough to know what might work and what might not. You
cant' just make substitution, but once you have some background, it's
easier to see what can be changed and what can't be.

Since I was generally stripping junk equipment and reusing the parts, I
early on got a replacement guide for one of the Big Replacement Lines.
These were a smaller set of parts that could be carried by stores, and
then the substitution guide would lead you to a part that was kind of
close.

I never bought the expensive replacement line parts, I just used it to
look up transistors in a circuit, and then look up trnasistors I had, and
then I'd find matches to the common replacement, or look up the specs of
the replacement and see if I was "close enough". Since many circuits were
just using transistors they had, "being close" was often good enough, so
long as I knew enough that that VHF circuit would need better transistors
than that audio amplifier, and so on.

It seems daunting going in, but it didn't take that long when I was a kid,
reading as much as I could get my hands on.

Michael

 

[Ivan Vegvary]

On Thursday, September 4, 2014 7:24:24 AM UTC-7, Ivan Vegvary wrote:

Want to breadboard small circuits from mid 1960's magazine articles.

Where on the web can I find today's equivalents for the specified transistors and diodes?

Just starting to learn solid state stuff.

Thanks!

Ivan Vegvary

In many cases I am looking for popular items like the "2N2222". Could I simply place a 2N2222 in an LTSpice circuit, study the outputs, and then substitute something similar (close) and compare outputs?
Trying to build (breadboard) simple projects like sine, square and sawtooth generators so I can play with my newly acquired (very old) Heathkit oscilloscope. Please don't laugh, it only cost $10, and is able to display 60Hz, 120V AC.
Of course it might make a lot more sense to abandon these old schematics and build from newer design, possibly available on the web, using currently available parts.

Thank you eveybody!! Your answers have inspired me.
Ivan Vegvary

 

[Tim Wescott]

On Thu, 04 Sep 2014 07:24:24 -0700, Ivan Vegvary wrote:

Want to breadboard small circuits from mid 1960's magazine articles.
Where on the web can I find today's equivalents for the specified
transistors and diodes?
Just starting to learn solid state stuff.
Thanks!
Ivan Vegvary

I'd start by looking to the hobby/surplus places for components -- for
silicon transistors, you may just find exactly what you want, instead of
equivalents.

All Electronics
MPJA Electronics
Jameco Electronics
Search on "surplus"

For germanium transistors, look on da bay -- I'm sure there are parts out
there.

For resistors and caps, for the most part, anything with the right value
will work.

And, as has been said -- if you're having trouble you can scan the
schematic, post it on some image-sharing site, then ask questions with a
link to the schematic and we'll help you out.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

 

[RobertMacy]

On Thu, 04 Sep 2014 12:00:42 -0700, Ivan Vegvary <ivanvegvary@gmail.com>
wrote:

...snip...
In many cases I am looking for popular items like the "2N2222". Could I
simply place a 2N2222 in an LTSpice circuit, study the outputs, and then
substitute something similar (close) and compare outputs?
Trying to build (breadboard) simple projects like sine, square and
sawtooth generators so I can play with my newly acquired (very old)
Heathkit oscilloscope. Please don't laugh, it only cost $10, and is
able to display 60Hz, 120V AC.
Of course it might make a lot more sense to abandon these old schematics
and build from newer design, possibly available on the web, using
currently available parts.

Thank you eveybody!! Your answers have inspired me.
Ivan Vegvary

you can use your soundcard to generate all kinds of waveforms.

 

[Tim Wescott]

On Thu, 04 Sep 2014 11:49:19 -0700, Ivan Vegvary wrote:

On Thursday, September 4, 2014 9:33:10 AM UTC-7, Tim Wescott wrote:
On Thu, 04 Sep 2014 07:24:24 -0700, Ivan Vegvary wrote:



Want to breadboard small circuits from mid 1960's magazine articles.

Where on the web can I find today's equivalents for the specified

transistors and diodes?

Just starting to learn solid state stuff.

Thanks!

Ivan Vegvary



I'd start by looking to the hobby/surplus places for components -- for

silicon transistors, you may just find exactly what you want, instead
of

equivalents.



All Electronics

MPJA Electronics

Jameco Electronics

Search on "surplus"



For germanium transistors, look on da bay -- I'm sure there are parts
out

there.



For resistors and caps, for the most part, anything with the right
value

will work.



And, as has been said -- if you're having trouble you can scan the

schematic, post it on some image-sharing site, then ask questions with
a

link to the schematic and we'll help you out.



--



Tim Wescott

Wescott Design Services

http://www.wescottdesign.com

Tim, I think I remember from your previous posts that you are from
Oregon. I live up in Sandy, OR. California transplant as of 11 years
ago.
Thanks for your help.

We're neighbors, then. I'm about 30 minutes from downtown Sandy, via
Estacada.

But my oldest Clackamas County roots go back a bit further, to the 1840's.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

 

[Tim Wescott]

On Thu, 04 Sep 2014 12:00:42 -0700, Ivan Vegvary wrote:

On Thursday, September 4, 2014 7:24:24 AM UTC-7, Ivan Vegvary wrote:
Want to breadboard small circuits from mid 1960's magazine articles.

Where on the web can I find today's equivalents for the specified
transistors and diodes?

Just starting to learn solid state stuff.

Thanks!

Ivan Vegvary

In many cases I am looking for popular items like the "2N2222". Could I
simply place a 2N2222 in an LTSpice circuit, study the outputs, and then
substitute something similar (close) and compare outputs?
Trying to build (breadboard) simple projects like sine, square and
sawtooth generators so I can play with my newly acquired (very old)
Heathkit oscilloscope. Please don't laugh, it only cost $10, and is
able to display 60Hz, 120V AC.
Of course it might make a lot more sense to abandon these old schematics
and build from newer design, possibly available on the web, using
currently available parts.

Thank you eveybody!! Your answers have inspired me.
Ivan Vegvary

The 2N3904 will substitute for the 2N2222 in just about anything. There's
also a "PN2222" that's supposedly a 2N2222 die in a TO-92 case.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

 

[George Herold]

On Thursday, September 4, 2014 6:06:07 PM UTC-4, Tim Wescott wrote:

On Thu, 04 Sep 2014 12:00:42 -0700, Ivan Vegvary wrote:


Thank you eveybody!! Your answers have inspired me.

Ivan Vegvary



The 2N3904 will substitute for the 2N2222 in just about anything. There's

also a "PN2222" that's supposedly a 2N2222 die in a TO-92 case.

Or 2N4401/ 4403 for pnp.

George H.

--



Tim Wescott

Wescott Design Services

http://www.wescottdesign.com

 

[Tim Wescott]

On Fri, 05 Sep 2014 06:18:50 -0700, George Herold wrote:

On Thursday, September 4, 2014 6:06:07 PM UTC-4, Tim Wescott wrote:
On Thu, 04 Sep 2014 12:00:42 -0700, Ivan Vegvary wrote:


Thank you eveybody!! Your answers have inspired me.

Ivan Vegvary



The 2N3904 will substitute for the 2N2222 in just about anything.
There's

also a "PN2222" that's supposedly a 2N2222 die in a TO-92 case.

Or 2N4401/ 4403 for pnp.

Somehow I fell into liking the 2N3904 / 2N3906 pair -- I don't know why,
and at this late date I can't justify it.

(Actually, when I'm prototyping with through-hole parts I have a small jar
marked NPN and another one marked PNP. 9 times out of 10 I just shake one
out of the jar, plug it in, and it works. The tenth time I actually have
to select something specific.)

These days if there's a transistor in one of my circuits, it's almost
always a dual or prebiased, it's in the smallest package that I feel up to
dealing with, and I just look for what's available on DigiKey.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

 

"Motorola used to sell those general purpose NPN and PNP transistors by
weight... it was too expensive to count them ;-) "

HAHAHAHA.

So what now, they got a machine to count them ? Or does some Chinese guy do it for 12 cents a day ?

 

[Bill Bowden]

"Tim Wescott" <seemywebsite@myfooter.really> wrote in message
news:Tc6dnaRcyKCreJTJnZ2dnUVZ5uudnZ2d@giganews.com...

On Fri, 05 Sep 2014 06:18:50 -0700, George Herold wrote:

On Thursday, September 4, 2014 6:06:07 PM UTC-4, Tim Wescott wrote:
On Thu, 04 Sep 2014 12:00:42 -0700, Ivan Vegvary wrote:


Thank you eveybody!! Your answers have inspired me.

Ivan Vegvary



The 2N3904 will substitute for the 2N2222 in just about anything.
There's

also a "PN2222" that's supposedly a 2N2222 die in a TO-92 case.

Or 2N4401/ 4403 for pnp.

Somehow I fell into liking the 2N3904 / 2N3906 pair -- I don't know why,
and at this late date I can't justify it.

(Actually, when I'm prototyping with through-hole parts I have a small jar
marked NPN and another one marked PNP. 9 times out of 10 I just shake one
out of the jar, plug it in, and it works. The tenth time I actually have
to select something specific.)

These days if there's a transistor in one of my circuits, it's almost
always a dual or prebiased, it's in the smallest package that I feel up to
dealing with, and I just look for what's available on DigiKey.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

I found abag of 2N4123 (NPN) (30V 200mA) that were damaged in a loading
machine. The leads all have little nicks and some leads are bent and ready
to fall off so I solder extention leads. Never counted them but they half
fill a coffee can. Maybe 2000 or so and the price was right at $3 for the
whole bag.




--- news://freenews.netfront.net/ - complaints: news@netfront.net ---

 

[Jim Thompson]

On Fri, 5 Sep 2014 14:37:38 -0700, "Bill Bowden"
<bperryb@bowdenshobbycircuits.info> wrote:

"Tim Wescott" <seemywebsite@myfooter.really> wrote in message
news:Tc6dnaRcyKCreJTJnZ2dnUVZ5uudnZ2d@giganews.com...
On Fri, 05 Sep 2014 06:18:50 -0700, George Herold wrote:

On Thursday, September 4, 2014 6:06:07 PM UTC-4, Tim Wescott wrote:
On Thu, 04 Sep 2014 12:00:42 -0700, Ivan Vegvary wrote:


Thank you eveybody!! Your answers have inspired me.

Ivan Vegvary



The 2N3904 will substitute for the 2N2222 in just about anything.
There's

also a "PN2222" that's supposedly a 2N2222 die in a TO-92 case.

Or 2N4401/ 4403 for pnp.

Somehow I fell into liking the 2N3904 / 2N3906 pair -- I don't know why,
and at this late date I can't justify it.

(Actually, when I'm prototyping with through-hole parts I have a small jar
marked NPN and another one marked PNP. 9 times out of 10 I just shake one
out of the jar, plug it in, and it works. The tenth time I actually have
to select something specific.)

These days if there's a transistor in one of my circuits, it's almost
always a dual or prebiased, it's in the smallest package that I feel up to
dealing with, and I just look for what's available on DigiKey.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

I found abag of 2N4123 (NPN) (30V 200mA) that were damaged in a loading
machine. The leads all have little nicks and some leads are bent and ready
to fall off so I solder extention leads. Never counted them but they half
fill a coffee can. Maybe 2000 or so and the price was right at $3 for the
whole bag.




--- news://freenews.netfront.net/ - complaints: news@netfront.net ---

Motorola used to sell those general purpose NPN and PNP transistors by
weight... it was too expensive to count them ;-)

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: skypeanalog | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

 

[Bill Bowden]

"Jim Thompson" <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote in
message news:gsbk0at5rmkvlfa2hisq8cj70mu8o6tpol@4ax.com...

On Fri, 5 Sep 2014 14:37:38 -0700, "Bill Bowden"
wrote:

I found abag of 2N4123 (NPN) (30V 200mA) that were damaged in a loading
machine. The leads all have little nicks and some leads are bent and ready
to fall off so I solder extention leads. Never counted them but they half
fill a coffee can. Maybe 2000 or so and the price was right at $3 for the
whole bag.


Motorola used to sell those general purpose NPN and PNP transistors by
weight... it was too expensive to count them ;-)

...Jim Thompson

I bet you don't have one of these ----: Toshiba MG240V1US41, 240 amp, 1700
volt, N channel IGBT, weighs 1 pound.


.



--- news://freenews.netfront.net/ - complaints: news@netfront.net ---

 

[Jim Thompson]

On Fri, 5 Sep 2014 17:30:34 -0700, "Bill Bowden"
<bperryb@bowdenshobbycircuits.info> wrote:

"Jim Thompson" <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote in
message news:gsbk0at5rmkvlfa2hisq8cj70mu8o6tpol@4ax.com...
On Fri, 5 Sep 2014 14:37:38 -0700, "Bill Bowden"
wrote:

I found abag of 2N4123 (NPN) (30V 200mA) that were damaged in a loading
machine. The leads all have little nicks and some leads are bent and ready
to fall off so I solder extention leads. Never counted them but they half
fill a coffee can. Maybe 2000 or so and the price was right at $3 for the
whole bag.


Motorola used to sell those general purpose NPN and PNP transistors by
weight... it was too expensive to count them ;-)

...Jim Thompson


I bet you don't have one of these ----: Toshiba MG240V1US41, 240 amp, 1700
volt, N channel IGBT, weighs 1 pound.

Nope.

Heaviest I ever got into was 600V NPN off-line switching devices at a
few Amperes... fractional ounces.

...Jim Thompson
--
| James E.Thompson | mens |
| Analog Innovations | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| San Tan Valley, AZ 85142 Skype: skypeanalog | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

 

[Maynard A. Philbrook Jr.]

In article <ludkjf$1lso$1@adenine.netfront.net>,
bperryb@bowdenshobbycircuits.info says...

"Jim Thompson" <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote in
message news:gsbk0at5rmkvlfa2hisq8cj70mu8o6tpol@4ax.com...
On Fri, 5 Sep 2014 14:37:38 -0700, "Bill Bowden"
wrote:

I found abag of 2N4123 (NPN) (30V 200mA) that were damaged in a loading
machine. The leads all have little nicks and some leads are bent and ready
to fall off so I solder extention leads. Never counted them but they half
fill a coffee can. Maybe 2000 or so and the price was right at $3 for the
whole bag.


Motorola used to sell those general purpose NPN and PNP transistors by
weight... it was too expensive to count them ;-)

...Jim Thompson


I bet you don't have one of these ----: Toshiba MG240V1US41, 240 amp, 1700
volt, N channel IGBT, weighs 1 pound.

It's only a N channel on the input and that only drives the base or
bases of the actual bipolar transistor, which is the part handling all
that current and voltage.

So one must understand that the V(ce)saturation voltage isn't going to
be low as you would expect otherwise.

Jamie