Tech: 1N270 Diode substitution

ScriptPirate

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Sep 1, 2009, 9:14:48 AM9/1/09

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Any idea what diode(s) can be used in place of a 1N270? 1N4148s I saw
referenced once.

Thanks

Vince

ScriptPirate

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Sep 1, 2009, 9:15:38 AM9/1/09

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Sorry, more info. this is for a Sinbad SS switch matrix.

Vince

Borygard

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Sep 1, 2009, 12:34:49 PM9/1/09

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1N4148 should be fine.

--
Rob Anthony
Pinball Classics
www.LockWhenLit.com
Quality Board Work - In Home Service
314-766-4587

"ScriptPirate" <script...@gmail.com> wrote in message
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ScriptPirate

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Sep 1, 2009, 12:53:34 PM9/1/09

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On Sep 1, 11:34 am, "Borygard" <Boryg...@gmail.com> wrote:
> 1N4148 should be fine.
>
> --
> Rob Anthony
> Pinball Classicswww.LockWhenLit.com
> Quality Board Work - In Home Service
> 314-766-4587
>

> "ScriptPirate" <scriptpir...@gmail.com> wrote in message

>
> news:caf9fed6-9b6f-4fa7...@s6g2000vbp.googlegroups.com...
>
>
>
> > Any idea what diode(s) can be used in place of a 1N270? 1N4148s I saw
> > referenced once.
>
> > Thanks
>

> > Vince- Hide quoted text -
>
> - Show quoted text -

Thanks Rob, RGP best help ever - as always.
Vince

Mark Clayton

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Sep 1, 2009, 12:54:21 PM9/1/09

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A 1N270 is germanium diode, which has a lower forward voltage drop
than a silicon diode like a 1N4148 or 1N4001.

A silicon diode may work as a replacement, but technically the
circuit will be out of spec and may be unreliable. Won't
do any harm to anything, though.

-Mark
-----
http://pinballpal.com

Chris Hibler

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Sep 1, 2009, 1:20:21 PM9/1/09

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On Sep 1, 11:54 am, Mark Clayton <spamuser1...@i87.com> wrote:
> A 1N270 is germanium diode, which has a lower forward voltage drop
> than a silicon diode like a 1N4148 or 1N4001.
>
> A silicon diode may work as a replacement, but technically the
> circuit will be out of spec and may be unreliable. Won't
> do any harm to anything, though.
>
> -Mark

> -----http://pinballpal.com

>
> ScriptPirate wrote:
> > Any idea what diode(s) can be used in place of a 1N270? 1N4148s I saw
> > referenced once.
>
> > Thanks
>
> > Vince

In the past, I've scavenged a 1N270 off the bottom board diode strip.
Choose a switch that you don't care about like maybe the center coin
chute switch. You could then put the silicon diode in it's place.
--
Chris Hibler - CARGPB #31
www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm

Borygard

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Sep 1, 2009, 1:53:33 PM9/1/09

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I realize the difference between the two diodes (germanium vs. silicon), but
have been using 1N4148s as replacements for years without any issues.

When I first started using them I checked their data sheets and they were
both at 200mA for forward voltage drop.

Hopefully if someone has different experiences with this they'll chime in.

--
Rob Anthony
Pinball Classics
www.LockWhenLit.com

Quality Board Work - In Home Service
314-766-4587

"Mark Clayton" <spamus...@i87.com> wrote in message
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Mark Clayton

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Sep 1, 2009, 3:09:27 PM9/1/09

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FYI, the forward voltage drop is measured in Volts, not Amperes.
The 200 mA (or whatever) is the current at which they measure the
voltage drop. Germanium is a different semiconductor material
than silicon, and it has an inherently lower forward voltage drop,
typically 0.4 Volts vs. 0.7 Volts for silicon.

As I said before, a silicon diode is still likely to work, it's
only a technical violation of the specs. Just as you could probably
put an 8 Amp fuse in place of a 10 Amp fuse and it would probably
"work fine" most of the time. There's no harm done, but it makes
the circuit suspect. Should any weirdnesses happen down the line,
that substitution should be considered a possible culprit.

Swapping out the diode with another on a less-used switch is
an excellent idea.

-Mark
-----
http://pinballpal.com

Borygard

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Sep 1, 2009, 3:20:05 PM9/1/09

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Thanks for the great info Mark.

--
Rob Anthony
Pinball Classics
www.LockWhenLit.com
Quality Board Work - In Home Service
314-766-4587

"Mark Clayton" <spamus...@i87.com> wrote in message

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Steve Kulpa

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Sep 1, 2009, 3:30:54 PM9/1/09

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On Sep 1, 12:53 pm, "Borygard" <Boryg...@gmail.com> wrote:
> I realize the difference between the two diodes (germanium vs. silicon), but
> have been using 1N4148s as replacements for years without any issues.
>
> When I first started using them I checked their data sheets and they were
> both at 200mA for forward voltage drop.
>
> Hopefully if someone has different experiences with this they'll chime in.
>
> --
> Rob Anthony
> Pinball Classicswww.LockWhenLit.com
> Quality Board Work - In Home Service
> 314-766-4587
>

> "Mark Clayton" <spamuser1...@i87.com> wrote in message

>
> news:4lcnm.711474$Tp1.5...@en-nntp-01.dc1.easynews.com...
>
> >A 1N270 is germanium diode, which has a lower forward voltage drop
> > than a silicon diode like a 1N4148 or 1N4001.
>
> > A silicon diode may work as a replacement, but technically the
> > circuit will be out of spec and may be unreliable. Won't
> > do any harm to anything, though.
>
> > -Mark
> > -----
> >http://pinballpal.com
>
> > ScriptPirate wrote:
> >> Any idea what diode(s) can be used in place of a 1N270? 1N4148s I saw
> >> referenced once.
>
> >> Thanks
>
> >> Vince

Big Daddy has the 1N270, plus a cheaper modern equivalent.

http://bigdaddy-enterprises.com/electronics/e_diodes.htm#rec-std

steve
---
Steve Kulpa (cargpb10)
Nolensville, TN
http://stevekulpa.net/faces/rgpidx.htm - Faces
http://stevekulpa.net/pinball/pinball.htm - Pinball