EDAboard.com | EDAboard.eu | EDAboard.de | EDAboard.co.uk | RTV forum PL | NewsGroups PL

Transistor identification?

Ask a question - edaboard.com

elektroda.net NewsGroups Forum Index - Electronics Components - Transistor identification?

Look165
Guest

Sun Sep 06, 2015 2:53 pm   



Previous post problem !

444 is 2N444

NPN Germanium TO5 15V 25mA 150mW 400 KHz : equivalent AC176 or 2N2430

John Robertson
Guest

Sun Sep 06, 2015 10:57 pm   



On 09/06/2015 1:53 AM, Look165 wrote:
Quote:
Previous post problem !

444 is 2N444

NPN Germanium TO5 15V 25mA 150mW 400 KHz : equivalent AC176 or 2N2430


Germanium? That is quite ancient - any designs from the 1970s on would
be silicon.

If the OP can check the rest of the device to get an idea of the age
that would help determine if it is possibly germanium.

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

Brian Gregory
Guest

Wed Sep 09, 2015 7:30 am   



On 06/09/2015 17:57, John Robertson wrote:
Quote:
On 09/06/2015 1:53 AM, Look165 wrote:
Previous post problem !

444 is 2N444

NPN Germanium TO5 15V 25mA 150mW 400 KHz : equivalent AC176 or 2N2430

Germanium? That is quite ancient - any designs from the 1970s on would
be silicon.

If the OP can check the rest of the device to get an idea of the age
that would help determine if it is possibly germanium.

John :-#)#


I don't recall ever seeing a germanium device in a modern plastic
package like that.

--

Brian Gregory (in the UK).
To email me please remove all the letter vee from my email address.

legg
Guest

Wed Sep 09, 2015 9:47 pm   



On Wed, 9 Sep 2015 03:38:00 +0100, Brian Gregory
<bvdvgvrvevgvovrvy_at_gmail.com> wrote:

Quote:
On 06/09/2015 17:57, John Robertson wrote:
On 09/06/2015 1:53 AM, Look165 wrote:
Previous post problem !

444 is 2N444

NPN Germanium TO5 15V 25mA 150mW 400 KHz : equivalent AC176 or 2N2430

Germanium? That is quite ancient - any designs from the 1970s on would
be silicon.

If the OP can check the rest of the device to get an idea of the age
that would help determine if it is possibly germanium.

John :-#)#


I don't recall ever seeing a germanium device in a modern plastic
package like that.


Only one or two germanium parts in TO92 - AF306 and AF339, but don't
forget plastic RF types in SOT37/TO119 'T' packaging.

If ever there was an electonic industry version of trivial persuit,
this would be a likely question.

RL

Ian Field
Guest

Fri Sep 18, 2015 1:22 am   



"legg" <legg_at_nospam.magma.ca> wrote in message
news:vhk0vap0db89svkvm5rqdd8qeg3aevnr6j_at_4ax.com...
Quote:
On Wed, 9 Sep 2015 03:38:00 +0100, Brian Gregory
bvdvgvrvevgvovrvy_at_gmail.com> wrote:

On 06/09/2015 17:57, John Robertson wrote:
On 09/06/2015 1:53 AM, Look165 wrote:
Previous post problem !

444 is 2N444

NPN Germanium TO5 15V 25mA 150mW 400 KHz : equivalent AC176 or 2N2430

Germanium? That is quite ancient - any designs from the 1970s on would
be silicon.

If the OP can check the rest of the device to get an idea of the age
that would help determine if it is possibly germanium.

John :-#)#


I don't recall ever seeing a germanium device in a modern plastic
package like that.

Only one or two germanium parts in TO92 - AF306 and AF339, but don't
forget plastic RF types in SOT37/TO119 'T' packaging.


The only plastic cased germanium transistors I've ever seen were UHF types
in TV tuners, AF139 or something like that.

They were pretty fragile - they weren't potted encapsulation, but 2 plastic
cups glues together to enclose the die header. A few fell apart as I tried
to unsolder them.

legg
Guest

Fri Sep 18, 2015 6:55 pm   



On Thu, 17 Sep 2015 20:22:17 +0100, "Ian Field"
<gangprobing.alien_at_ntlworld.com> wrote:

Quote:

"legg" <legg_at_nospam.magma.ca> wrote in message
news:vhk0vap0db89svkvm5rqdd8qeg3aevnr6j_at_4ax.com...
On Wed, 9 Sep 2015 03:38:00 +0100, Brian Gregory
bvdvgvrvevgvovrvy_at_gmail.com> wrote:

On 06/09/2015 17:57, John Robertson wrote:
On 09/06/2015 1:53 AM, Look165 wrote:
Previous post problem !

444 is 2N444

NPN Germanium TO5 15V 25mA 150mW 400 KHz : equivalent AC176 or 2N2430

Germanium? That is quite ancient - any designs from the 1970s on would
be silicon.

If the OP can check the rest of the device to get an idea of the age
that would help determine if it is possibly germanium.

John :-#)#


I don't recall ever seeing a germanium device in a modern plastic
package like that.

Only one or two germanium parts in TO92 - AF306 and AF339, but don't
forget plastic RF types in SOT37/TO119 'T' packaging.

The only plastic cased germanium transistors I've ever seen were UHF types
in TV tuners, AF139 or something like that.

They were pretty fragile - they weren't potted encapsulation, but 2 plastic
cups glues together to enclose the die header. A few fell apart as I tried
to unsolder them.


That's the SOT37/TO119 package intended for stripline UHF. I can
assure you that reputable vendor parts (like AF279 AF280 -
siemens/valvo/telefunken) were encapsulated in solid molded bodies.
I can send you some 'decap' images if you'd like.

This may have required a two-stage process, initially, but the
construction that you describe, with no die or lead support, in a
plastic shell, would not have survived common manual soldering and
assembly methods.

Even parts assembled inside TO18/TO72 cans (as AF139), or TO1 glass
envelopes, relied on an internal fill/coating, for die and bonding
surface integrity. Even then, niether were expected to survive severe
lead-out mis-manipulation that could occur in careless lead forming or
point-to-point wiring assembly methods.......

Earliest pro-electron germanium parts in SOT37 were AF2xx or higher.
In TO92, only the two numbers listed previously. All low power
VHF/UHF.

RL

elektroda.net NewsGroups Forum Index - Electronics Components - Transistor identification?

Ask a question - edaboard.com

Arabic versionBulgarian versionCatalan versionCzech versionDanish versionGerman versionGreek versionEnglish versionSpanish versionFinnish versionFrench versionHindi versionCroatian versionIndonesian versionItalian versionHebrew versionJapanese versionKorean versionLithuanian versionLatvian versionDutch versionNorwegian versionPolish versionPortuguese versionRomanian versionRussian versionSlovak versionSlovenian versionSerbian versionSwedish versionTagalog versionUkrainian versionVietnamese versionChinese version
RTV map EDAboard.com map News map EDAboard.eu map EDAboard.de map EDAboard.co.uk map