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Help identifying components

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DaveC

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Sep 25, 2010, 12:28:08 AM9/25/10
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Black diode, smaller than 1Nxxx, green band and green test: "R47".

Glass diode with yellow band. No other markings.

Thanks.

tm

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Sep 25, 2010, 12:39:27 AM9/25/10
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"DaveC" <inv...@invalid.net> wrote in message
news:0001HW.C8C2C868...@news.eternal-september.org...

> Black diode, smaller than 1Nxxx, green band and green test: "R47".
>
> Glass diode with yellow band. No other markings.
>
> Thanks.
>
What are they in? A little context would help.


DaveC

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Sep 25, 2010, 12:48:41 AM9/25/10
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> Black diode, smaller than 1Nxxx, green band and green test: "R47".

should say 'green text: "R47" '.

Thanks.

DaveC

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Sep 25, 2010, 12:59:14 AM9/25/10
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> What are they in? A little context would help.

The circuit is in a Hakko 472 desolder station. It controls the switching on
and off of the vacuum pump motor and vacuum solenoid valve.

Thanks.

Tim Williams

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Sep 25, 2010, 1:01:47 AM9/25/10
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DIAC?

I have some diodes of similar appearance on RF equipment. I'm guessing
they are either schottky or varactor. YMMV, could be a manufacturer
thing.

Tim

--
Deep Friar: a very philosophical monk.
Website: http://webpages.charter.net/dawill/tmoranwms


"DaveC" <inv...@invalid.net> wrote in message

news:0001HW.C8C2CFB2...@news.eternal-september.org...

DaveC

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Sep 25, 2010, 1:04:40 AM9/25/10
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> Second unit is probably a Ge diode like 1N34A

Measures 0.59v drop. So: silicon.

DaveC

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Sep 25, 2010, 1:16:44 AM9/25/10
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Does the fact that both show ~ 0.6 v-drop rule out zeners?

Thanks.

tm

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Sep 25, 2010, 1:48:40 AM9/25/10
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"DaveC" <inv...@invalid.net> wrote in message
news:0001HW.C8C2D3CC...@news.eternal-september.org...

> Does the fact that both show ~ 0.6 v-drop rule out zeners?
>
> Thanks.
>

No, only that they are most likely silicon. The zener effect is the reverse
breakdown
voltage. You need to dope out the circuit more to see if it could be a
zener.


tm

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Sep 25, 2010, 1:59:41 AM9/25/10
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"DaveC" <inv...@invalid.net> wrote in message
news:0001HW.C8C2CFB2...@news.eternal-september.org...

Are the vacuum pump and solenoid AC or DC devices?

Is there a SCR in there?

See if this schematic has any think close to what you have:

http://www.eserviceinfo.com/downloadsm/37779/Hakko_850B.html


tm

Lostgallifreyan

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Sep 25, 2010, 4:11:14 AM9/25/10
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DaveC <inv...@invalid.net> wrote in
news:0001HW.C8C2D3CC...@news.eternal-september.org:

> Does the fact that both show ~ 0.6 v-drop rule out zeners?
>
> Thanks.
>
>

You sound like a man who imagines that by scrunchign his shoulders, no-one
will mind when he passes annopyingly several times through the same doorway.
>:)

And no. To test a zener you need to try a reverse voltage. Try a variable
voltage through a 10K resistor. A sine wave off a 30V transformer will do,
just look for the clipping voltages on a scope (or DC voltmeter if you add a
capacitor in parallel with the diode). Vz equals peak-peak voltage minus
about 0.58V. You may also have to remove one end of it from the circuit to be
certain.

Lostgallifreyan

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Sep 25, 2010, 4:23:51 AM9/25/10
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Lostgallifreyan <no-...@nowhere.net> wrote in
news:Xns9DFE5D70DE9...@216.196.109.145:

> Vz equals peak-peak voltage minus
> about 0.58V.

Evidently my turn to pass annoying through the same doorway...

Scratch that, the rest stands though, you just have to do the test once for
each polarity of that diode. (You'll only see both peaks at once if you have
a zero-referenced AC voltage, and even then that capacitor idea wouldn't
apply, and I made it more complex than it needs to be, you only need to see
the zener peak to know...).

DaveC

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Sep 25, 2010, 1:40:46 PM9/25/10
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> Are the vacuum pump and solenoid AC or DC devices?

AC

> Is there a SCR in there?

2 triacs: one for the motor, one for the solenoid.

> See if this schematic has any think close to what you have:
>
> http://www.eserviceinfo.com/downloadsm/37779/Hakko_850B.html

Not much similarity. The 850 uses a 120vac motor; the 472 uses a 35 vac
motor. The 850 has no solenoid.

Thanks.

DaveC

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Sep 25, 2010, 8:04:20 PM9/25/10
to
Do zeners come in both glass & plastic packages?

Thanks.

Ross Herbert

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Sep 25, 2010, 9:42:32 PM9/25/10
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On Sat, 25 Sep 2010 17:04:20 -0700, DaveC <inv...@invalid.net> wrote:

:Do zeners come in both glass & plastic packages?
:
:Thanks.


Yes they do..

DaveC

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Sep 25, 2010, 11:13:43 PM9/25/10
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> Even without the "variable" this can work. Use a high enough DC voltage.
>
> There is a method with a scope, resistor and AC supply but it is much more
> complex for a novice (assuming)

I got the scope, resistor(s). Variac + small transformer = variable AC
supply.

So describe away!

Thanks.

Rich Grise

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Sep 26, 2010, 12:01:39 AM9/26/10
to
On Sat, 25 Sep 2010 17:04:20 -0700, DaveC wrote:

> Do zeners come in both glass & plastic packages?
>

Not simultaneously. ;-P

Cheers!
Rich


Randy

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Sep 26, 2010, 2:28:27 AM9/26/10
to

I may have the answer, but No, I can't help you....but you can go
through books and mfg semiconductor spec manuals....you can fish
through IR's site too.
I have a power supply myself that I need to boost to about 50 watts
continuous, the coil can bolster it but I have to rebuild the network
and upgrade a full bridge inhabited by dubious trolls..... hahaha.
Maybe I'll just send away for a new dedicated unit made to
specifications, the digits are unquestionable., the markings as
diverse as makers......Good Luck!
R.

DaveC

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Sep 26, 2010, 11:46:08 AM9/26/10
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> I may have the answer, but No, I can't help you....

???

Josepi

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Sep 26, 2010, 1:14:42 PM9/26/10
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hmmmm... Now you are pushing my memory hard!!...LOL

Let's see.

Make a series circuit with the resistor (R) at the top and the component at
the bottom. Feed the whole thing with an AC voltage supply, top to bottom.

You will need a scope with horizontal input as well as the usual vertical
input and a floating ground or full differential input somwehere. (you work
out the logic .. maybe a floating AC voltage supply would be enough)

Hook the vertical input across the resistor and the horizontal input across
the component. Maybe the grounds together in the middle of components and
floating supply are good for that??? Been a few years.

Now your vertical trace on the scope indicates current (IR drop in the
resistor).
The horizontal trace indicates voltage drop across the component.
You will get the single curve of a component tracer on your scope.

***Component curves***
**shorted = vertical line
**open = horizontal line
**resistor same as R = 45 degree line
**capacitor = circle... me thinks round indicates matching impedance with R
at 60Hz??
** inductor = circle same as cap above??
**zener no current at lower voltages = horiz. line; no voltage increase at
higher voltages = vertical line = visible knee at zener voltage - use
calibrated scales for measurement
**avalanche diode = horizonatal line with foldback and shows current
(vertical at higher end)

Try it! So simple it stinks but is very visible clue. Watch your scope
grounding.

"DaveC" <inv...@invalid.net> wrote in message

news:0001HW.C8C40877...@news.eternal-september.org...

Tim Williams

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Sep 26, 2010, 1:23:42 PM9/26/10
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"Rich Grise" <rich...@example.net> wrote in message
news:pan.2010.09.26....@example.net...

>> Do zeners come in both glass & plastic packages?
>
> Not simultaneously. ;-P

What about glass passivated, plastic package diodes? ;o)

Michael A. Terrell

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Sep 26, 2010, 3:56:33 PM9/26/10
to

DaveC wrote:
>
> > I may have the answer, but No, I can't help you....
>
> ???

|----||----|
| DO NOT |
| FEED THE |
| TROLLS! |
|----||----|
||
||
||
/|\\|/||||//|||/\???\\//\\\\/|?\/\\\\/\/\/\||||\
--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.

dca...@krl.org

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Sep 26, 2010, 7:44:24 PM9/26/10
to

I would trace out the circuitry. If you have that, then the type of
diode may be obvious. For example if a diode is across a relay coil
to eliminate transcients, then any ordinary diode will work. For a
circuit for a desolder station, I would expect all the diode would be
common diodes, no zeners, no fast switching, no germanium. Just
something like a 1N4004.

Dan

Randy

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Sep 26, 2010, 8:23:44 PM9/26/10
to
On Sep 26, 3:56 pm, "Michael A. Terrell" <mike.terr...@earthlink.net>
wrote:

Cut it out Michael..
R.

Randy

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Sep 26, 2010, 9:58:23 PM9/26/10
to
On Sep 26, 3:56 pm, "Michael A. Terrell" <mike.terr...@earthlink.net>
wrote:

Fix the sign or for pete's sake, Do Not Use It Again.
R.

Michael A. Terrell

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Sep 27, 2010, 12:12:00 AM9/27/10
to

Responding just
encourages them!
\
>')
( \
^^`

neddie

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Sep 29, 2010, 6:52:11 AM9/29/10
to
> "DaveC" <inva...@invalid.net> wrote in message

>
> news:0001HW.C8C40877...@news.eternal-september.org...
> I got the scope, resistor(s). Variac + small transformer = variable AC
> supply.
>
> So describe away!
>
> Thanks.
>
> > Even without the "variable" this can work. Use a high enough DC voltage.
>
> > There is a method with a scope, resistor and AC supply  but it is much
> > more
> > complex for a novice (assuming)

Sim this in LTSpice

Version 4
SHEET 1 880 680
WIRE 64 64 -16 64
WIRE 224 64 144 64
WIRE 256 64 224 64
WIRE -16 128 -16 64
WIRE 224 144 224 64
WIRE -16 272 -16 208
WIRE 112 272 -16 272
WIRE 224 272 224 208
WIRE 224 272 112 272
WIRE 112 288 112 272
FLAG 112 288 0
FLAG 256 64 Vout
SYMBOL zener 240 208 R180
WINDOW 0 24 72 Left 0
WINDOW 3 -145 31 Left 0
SYMATTR InstName D1
SYMATTR Value BZX84C15L
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL res 160 48 R90
WINDOW 0 0 56 VBottom 0
WINDOW 3 32 56 VTop 0
SYMATTR InstName R1
SYMATTR Value 47k
SYMBOL voltage -16 112 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value SINE(0 30 50)
TEXT -50 312 Left 0 !.tran 200m

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