Help identifying components

D

DaveC

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Black diode, smaller than 1Nxxx, green band and green test: "R47".

Glass diode with yellow band. No other markings.

Thanks.
 
"DaveC" <invalid@invalid.net> wrote in message
news:0001HW.C8C2C86803107F42B01AD9AF@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.
Click to expand...
 
What are they in? A little context would help.
Click to expand...
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.
 
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" <invalid@invalid.net> wrote in message
news:0001HW.C8C2CFB2031234C6B01AD9AF@news.eternal-september.org...
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.
Click to expand...
 
Does the fact that both show ~ 0.6 v-drop rule out zeners?

Thanks.
 
"DaveC" <invalid@invalid.net> wrote in message
news:0001HW.C8C2D3CC03132ACCB01AD9AF@news.eternal-september.org...
Does the fact that both show ~ 0.6 v-drop rule out zeners?

Thanks.
Click to expand...
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.
 
"DaveC" <invalid@invalid.net> wrote in message
news:0001HW.C8C2CFB2031234C6B01AD9AF@news.eternal-september.org...
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.
Click to expand...
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
 
DaveC <invalid@invalid.net> wrote in
news:0001HW.C8C2D3CC03132ACCB01AD9AF@news.eternal-september.org:

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

Thanks.
Click to expand...
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.
:)
Click to expand...
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 <no-one@nowhere.net> wrote in
news:Xns9DFE5D70DE9FCzoodlewurdle@216.196.109.145:

Vz equals peak-peak voltage minus
about 0.58V.
Click to expand...
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...).
 
Are the vacuum pump and solenoid AC or DC devices?
Click to expand...
AC

Is there a SCR in there?
Click to expand...
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
Click to expand...
Not much similarity. The 850 uses a 120vac motor; the 472 uses a 35 vac
motor. The 850 has no solenoid.

Thanks.
 
On Sat, 25 Sep 2010 17:04:20 -0700, DaveC <invalid@invalid.net> wrote:

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


Yes they do..
 
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)
Click to expand...
I got the scope, resistor(s). Variac + small transformer = variable AC
supply.

So describe away!

Thanks.
 
On Sat, 25 Sep 2010 17:04:20 -0700, DaveC wrote:

Do zeners come in both glass & plastic packages?

Not simultaneously. ;-P
Click to expand...

Cheers!
Rich
 
On Sep 25, 12:28 am, DaveC <inva...@invalid.net> wrote:
Black diode, smaller than 1Nxxx, green band and green test: "R47".

Glass diode with yellow band. No other markings.

Thanks.
Click to expand...
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.
 
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" <invalid@invalid.net> wrote in message
news:0001HW.C8C40877035B8296B01AD9AF@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)
Click to expand...
 
"Rich Grise" <richgrise@example.net> wrote in message
news:pan.2010.09.26.04.01.38.367112@example.net...
Do zeners come in both glass & plastic packages?

Not simultaneously. ;-P
Click to expand...
What about glass passivated, plastic package diodes? ;o)

Tim

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