[TriEmbed] TriEmbed Digest, Vol 11, Issue 7
Martin Brooke
martin.brooke at duke.edu
Sat Apr 5 15:51:01 CDT 2014
The shelf life stuff is nonsense unless you are doing mass production and
want very high yields.
Do however be careful of static electricity. I assemble my stuff on a
large sheet of aluminum foil that I connect to a power supply ground (or
connect to something large and metal like house plumbing) and touch all the
time.
Static is absolutely not a problem when the humidity is over 45% however,
so working on a rainy day is fine.
On Fri, Apr 4, 2014 at 8:42 PM, <triembed-request at triembed.org> wrote:
> Send TriEmbed mailing list submissions to
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>
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>
> Today's Topics:
>
> 1. Re: TriEmbed Digest, Vol 11, Issue 6 (Charles McClelland)
> 2. Re: TriEmbed Digest, Vol 11, Issue 6 (Carl Nobile)
>
>
> ---------- Forwarded message ----------
> From: Charles McClelland <chip at mcclellands.org>
> To: triembed at triembed.org
> Cc:
> Date: Fri, 4 Apr 2014 20:31:15 -0400
> Subject: Re: [TriEmbed] TriEmbed Digest, Vol 11, Issue 6
> Pete, Carl and All,
>
> Thanks for your advice on this topic. I wanted to take a look at the
> components and I have a couple more questions if I can:
>
> - Optics - My magnifying glass is not strong enough to read the marking
> clearly on the components. I can make out some of the numbers (like 102
> which I assume means 10x10^2 on the 1k resistors) but it is tough. I know
> Pete is not satisfied with the USB microscope he got from Adafruit but,
> what do you all use to inspect these parts?
>
> - Markings - not all the parts even have markings. The capacitors do not
> seem to be marked at all leaving me to wonder how I can be sure of the part
> I am using. Do I need something like this:
> https://www.sparkfun.com/products/10829
>
> - Shelf life - According to the markings on the bag, the ATMEGA328 SMD
> chips need to be installed within 168 hours of opening the bag. Unless the
> approach Pete laid out below works, it seems I need to buy these chips as I
> need them which might get expensive. The other humidity sensitive part -
> the LEDs - say they need to be installed within a week. I had no idea
> some of these parts had the shelf life of lettuce. Is there a local
> supplier?
>
> Thanks again for putting up with my SMD-newbie questions.
>
> Chip
>
>
> On Apr 4, 2014, at 6:28 PM, triembed-request at triembed.org wrote:
>
> > Send TriEmbed mailing list submissions to
> > triembed at triembed.org
> >
> > To subscribe or unsubscribe via the World Wide Web, visit
> > http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
> > or, via email, send a message with subject or body 'help' to
> > triembed-request at triembed.org
> >
> > You can reach the person managing the list at
> > triembed-owner at triembed.org
> >
> > When replying, please edit your Subject line so it is more specific
> > than "Re: Contents of TriEmbed digest..."
> >
> >
> > Today's Topics:
> >
> > 1. Surface Mount Components Newbie Questions (Charles McClelland)
> > 2. Fwd: Surface Mount Components Newbie Questions (Carl Nobile)
> > 3. Re: Surface Mount Components Newbie Questions (Carl Nobile)
> > 4. Re: Surface Mount Components Newbie Questions (Pete Soper)
> >
> >
> > ----------------------------------------------------------------------
> >
> > Message: 1
> > Date: Fri, 4 Apr 2014 16:38:32 -0400
> > From: Charles McClelland <chip at mcclellands.org>
> > To: TriEmbed Discussion <triembed at triembed.org>
> > Subject: [TriEmbed] Surface Mount Components Newbie Questions
> > Message-ID: <9D001F91-9195-4A64-AD0C-B360E3836CEF at mcclellands.org>
> > Content-Type: text/plain; charset=us-ascii
> >
> > Hey all,
> >
> > I am gearing up for my first surface mount project. OSH Park has just
> told me the boards are in the mail and DigiKey just sent me the bill of
> materials. I have some questions now that I have opened the box from
> DigiKey:
> >
> > 1) Some of the components claim to be humidity sensitive. Is this a big
> deal for hobby use? Do I need to keep these in a sealed bag with desiccant
> or is that overkill?
> >
> > 2) Some of the components claim to be sensitive to electrostatic
> discharge. I have yet to fry a through hold component - are surface mount
> components more sensitive?
> >
> > 3) The components come on tape which will be inefficient to store using
> the cool storage boxes Pete showed me. Is there anything wrong with
> removing the parts from the tape?
> >
> > I went with 0805 components so nothing is microscopic.
> >
> > Thanks,
> >
> > Chip
> >
> >
> >
> >
> >
> > ------------------------------
> >
> > Message: 2
> > Date: Fri, 4 Apr 2014 16:55:57 -0400
> > From: Carl Nobile <carl.nobile at gmail.com>
> > To: TriEmbed <TriEmbed at triembed.org>
> > Subject: [TriEmbed] Fwd: Surface Mount Components Newbie Questions
> > Message-ID:
> > <CAGQqDQKgkOYCM0U6sC7ynUsT6ykGEVjX6wz=
> eh71CFDLDkEU2g at mail.gmail.com>
> > Content-Type: text/plain; charset="utf-8"
> >
> > Sorry I sent this to Chip and forgot to click all.
> >
> > Chip,
> >
> > The static issue is the one to be very careful about. If you walk on a
> > staticky rug then touch a component, say good by to the component. At the
> > point where you can feel a shock it is already way too high and will blow
> > any static sensitive component. They must be kept in one of those dark
> gray
> > static bags. DO NOT use the pink ones, they're useless.
> >
> > BTW, components do not know if you are a hobbyist or a professional, if
> the
> > component doesn't like the humidity it will be damaged in either case.
> >
> > I always keep most parts in sealed plastic bags. If static electricity is
> > not an issue, like with resistors and capacitors, you can use clear
> plastic
> > bags. I get them at hobby stores, they come in all the right sizes and
> are
> > pretty cheap.
> >
> > Carl
> >
> >
> >
> > On Fri, Apr 4, 2014 at 4:38 PM, Charles McClelland <chip at mcclellands.org
> >wrote:
> >
> >> Hey all,
> >>
> >> I am gearing up for my first surface mount project. OSH Park has just
> >> told me the boards are in the mail and DigiKey just sent me the bill of
> >> materials. I have some questions now that I have opened the box from
> >> DigiKey:
> >>
> >> 1) Some of the components claim to be humidity sensitive. Is this a big
> >> deal for hobby use? Do I need to keep these in a sealed bag with
> desiccant
> >> or is that overkill?
> >>
> >> 2) Some of the components claim to be sensitive to electrostatic
> >> discharge. I have yet to fry a through hold component - are surface
> mount
> >> components more sensitive?
> >>
> >> 3) The components come on tape which will be inefficient to store using
> >> the cool storage boxes Pete showed me. Is there anything wrong with
> >> removing the parts from the tape?
> >>
> >> I went with 0805 components so nothing is microscopic.
> >>
> >> Thanks,
> >>
> >> Chip
> >>
> >>
> >>
> >> _______________________________________________
> >> Triangle, NC Embedded Computing mailing list
> >> TriEmbed at triembed.org
> >> http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
> >> TriEmbed web site: http://TriEmbed.org
> >>
> >
> >
> >
> > --
> >
> -------------------------------------------------------------------------------
> > Carl J. Nobile (Software Engineer)
> > carl.nobile at gmail.com
> >
> -------------------------------------------------------------------------------
> >
> >
> >
> >
> > --
> >
> -------------------------------------------------------------------------------
> > Carl J. Nobile (Software Engineer)
> > carl.nobile at gmail.com
> >
> -------------------------------------------------------------------------------
> > -------------- next part --------------
> > An HTML attachment was scrubbed...
> > URL: <
> http://mail.triembed.org/pipermail/triembed_triembed.org/attachments/20140404/ac4b06d5/attachment-0001.html
> >
> >
> > ------------------------------
> >
> > Message: 3
> > Date: Fri, 4 Apr 2014 17:31:48 -0400
> > From: Carl Nobile <carl.nobile at gmail.com>
> > To: Charles McClelland <chip at mcclellands.org>, TriEmbed
> > <TriEmbed at triembed.org>
> > Subject: Re: [TriEmbed] Surface Mount Components Newbie Questions
> > Message-ID:
> > <CAGQqDQ+8g=
> uXYw7s-9pgBBMcwZ66Fp7y4ZFNs0UV0gBFGUWfpA at mail.gmail.com>
> > Content-Type: text/plain; charset="utf-8"
> >
> > Chip,
> >
> > You have a point about the automated machines, if the humidity is high
> the
> > machines may malfunction. However, I do know of components that have
> > humidity issues also like some capacitors. It is not the water itself
> > which, by-the-way, will not conduct electricity, it's the impurities in
> the
> > water that is the issue. Humidity can change a crystal's frequency. When
> I
> > used to work on transmitters the oscillators were put into a heated box
> so
> > the radio/TV station would not drift off frequency. An FCC pink slip
> would
> > show up in the stations mail box with a hefty fine attached if the
> station
> > frequency did drift.
> >
> > I usually leave the parts on the ribbon tape and fold them up and put
> them
> > in a bag. Too much work taking them all apart and getting them mixed up
> > with other like parts.
> >
> > Carl
> >
> >
> >
> > On Fri, Apr 4, 2014 at 5:14 PM, Charles McClelland <chip at mcclellands.org
> >wrote:
> >
> >> Carl,
> >>
> >> Thanks, I guess I do need to think about static. I also like you
> plastic
> >> bag idea.
> >>
> >> On your point about hobbits or professional, let me explain what I was
> >> thinking. I assume that the reason many of these components are sold
> as
> >> cut tape is to accommodate the hobbyist who wants to order just a few.
> >> However, I am assuming that these same components are sold in entire
> reels
> >> of tape to the professional who might use an automated machine to place
> >> them on a board as part of a production line process. I guess I was
> >> wondering if it was the performance of these components in one of these
> >> automated production lines where humidity is an issue. Otherwise, will
> >> that sensitivity to humidity be an issue for the component on the
> assembled
> >> board?
> >>
> >> Thanks,
> >>
> >> Chip
> >>
> >>
> >> On Apr 4, 2014, at 4:51 PM, Carl Nobile <carl.nobile at gmail.com> wrote:
> >>
> >> Chip,
> >>
> >> The static issue is the one to be very careful about. If you walk on a
> >> staticky rug then touch a component, say good by to the component. At
> the
> >> point where you can feel a shock it is already way too high and will
> blow
> >> any static sensitive component. They must be kept in one of those dark
> gray
> >> static bags. DO NOT use the pink ones, they're useless.
> >>
> >> BTW, components do not know if you are a hobbyist or a professional, if
> >> the component doesn't like the humidity it will be damaged in either
> case.
> >>
> >> I always keep most parts in sealed plastic bags. If static electricity
> is
> >> not an issue, like with resistors and capacitors, you can use clear
> plastic
> >> bags. I get them at hobby stores, they come in all the right sizes and
> are
> >> pretty cheap.
> >>
> >> Carl
> >>
> >>
> >>
> >> On Fri, Apr 4, 2014 at 4:38 PM, Charles McClelland <
> chip at mcclellands.org>wrote:
> >>
> >>> Hey all,
> >>>
> >>> I am gearing up for my first surface mount project. OSH Park has just
> >>> told me the boards are in the mail and DigiKey just sent me the bill of
> >>> materials. I have some questions now that I have opened the box from
> >>> DigiKey:
> >>>
> >>> 1) Some of the components claim to be humidity sensitive. Is this a
> big
> >>> deal for hobby use? Do I need to keep these in a sealed bag with
> desiccant
> >>> or is that overkill?
> >>>
> >>> 2) Some of the components claim to be sensitive to electrostatic
> >>> discharge. I have yet to fry a through hold component - are surface
> mount
> >>> components more sensitive?
> >>>
> >>> 3) The components come on tape which will be inefficient to store using
> >>> the cool storage boxes Pete showed me. Is there anything wrong with
> >>> removing the parts from the tape?
> >>>
> >>> I went with 0805 components so nothing is microscopic.
> >>>
> >>> Thanks,
> >>>
> >>> Chip
> >>>
> >>>
> >>>
> >>> _______________________________________________
> >>> Triangle, NC Embedded Computing mailing list
> >>> TriEmbed at triembed.org
> >>> http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
> >>> TriEmbed web site: http://TriEmbed.org <http://triembed.org/>
> >>>
> >>
> >>
> >>
> >> --
> >>
> >>
> -------------------------------------------------------------------------------
> >> Carl J. Nobile (Software Engineer)
> >> carl.nobile at gmail.com
> >>
> -------------------------------------------------------------------------------
> >>
> >>
> >>
> >>
> >
> >
> > --
> >
> -------------------------------------------------------------------------------
> > Carl J. Nobile (Software Engineer)
> > carl.nobile at gmail.com
> >
> -------------------------------------------------------------------------------
> > -------------- next part --------------
> > An HTML attachment was scrubbed...
> > URL: <
> http://mail.triembed.org/pipermail/triembed_triembed.org/attachments/20140404/b42fbaee/attachment-0001.html
> >
> >
> > ------------------------------
> >
> > Message: 4
> > Date: Fri, 04 Apr 2014 18:28:33 -0400
> > From: Pete Soper <pete at soper.us>
> > To: triembed at triembed.org
> > Subject: Re: [TriEmbed] Surface Mount Components Newbie Questions
> > Message-ID: <533F3211.8000906 at soper.us>
> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> >
> > I leave those chips in their bags. Inside with the chips are bags of
> > desiccants. I'm told that the basic issue is that if the chip absorbs
> > much moisture then when it goes through the reflow oven it can
> > "popcorn." I don't need to describe what that means. I leave chips like
> > this in the bags, then when I'm going to use a fraction of them I put
> > the remainder with the desiccant bags into airtight containers with the
> > humidity test strips. This may be overkill.
> >
> > And as I type this I'm about to test out the low tech hood and vent
> > system for my oven. This is a very small oven and I have a very powerful
> > fan pushing air out of the basement, so hopefully I won't have to run
> > the oven outdoors in the near future.
> > -Pete
> >
> > On 04/04/2014 04:38 PM, Charles McClelland wrote:
> >> Hey all,
> >>
> >> I am gearing up for my first surface mount project. OSH Park has just
> told me the boards are in the mail and DigiKey just sent me the bill of
> materials. I have some questions now that I have opened the box from
> DigiKey:
> >>
> >> 1) Some of the components claim to be humidity sensitive. Is this a
> big deal for hobby use? Do I need to keep these in a sealed bag with
> desiccant or is that overkill?
> >>
> >> 2) Some of the components claim to be sensitive to electrostatic
> discharge. I have yet to fry a through hold component - are surface mount
> components more sensitive?
> >>
> >> 3) The components come on tape which will be inefficient to store using
> the cool storage boxes Pete showed me. Is there anything wrong with
> removing the parts from the tape?
> >>
> >> I went with 0805 components so nothing is microscopic.
> >>
> >> Thanks,
> >>
> >> Chip
> >>
> >>
> >>
> >> _______________________________________________
> >> Triangle, NC Embedded Computing mailing list
> >> TriEmbed at triembed.org
> >> http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
> >> TriEmbed web site: http://TriEmbed.org
> >
> >
> >
> >
> > ------------------------------
> >
> > Subject: Digest Footer
> >
> > _______________________________________________
> > TriEmbed mailing list
> > TriEmbed at triembed.org
> > http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
> >
> >
> > ------------------------------
> >
> > End of TriEmbed Digest, Vol 11, Issue 6
> > ***************************************
>
>
>
>
>
> ---------- Forwarded message ----------
> From: Carl Nobile <carl.nobile at gmail.com>
> To: Charles McClelland <chip at mcclellands.org>
> Cc: TriEmbed <triembed at triembed.org>
> Date: Fri, 4 Apr 2014 20:42:02 -0400
> Subject: Re: [TriEmbed] TriEmbed Digest, Vol 11, Issue 6
> Chip,
>
> I have never heard of shelf lives that short myself. I really cannot
> believe that an microcontroller will go bad after 168 hrs.
>
> As far as optics are concerned I have an assortment of eye pieces, my most
> used one by far is a 14X eye piece.
>
> As far as the caps are concerned get yourself a good digital multimeter,
> most have capacitance meters built in.
>
> Carl
>
>
>
>
> On Fri, Apr 4, 2014 at 8:31 PM, Charles McClelland <chip at mcclellands.org>wrote:
>
>> Pete, Carl and All,
>>
>> Thanks for your advice on this topic. I wanted to take a look at the
>> components and I have a couple more questions if I can:
>>
>> - Optics - My magnifying glass is not strong enough to read the marking
>> clearly on the components. I can make out some of the numbers (like 102
>> which I assume means 10x10^2 on the 1k resistors) but it is tough. I know
>> Pete is not satisfied with the USB microscope he got from Adafruit but,
>> what do you all use to inspect these parts?
>>
>> - Markings - not all the parts even have markings. The capacitors do not
>> seem to be marked at all leaving me to wonder how I can be sure of the part
>> I am using. Do I need something like this:
>> https://www.sparkfun.com/products/10829
>>
>> - Shelf life - According to the markings on the bag, the ATMEGA328 SMD
>> chips need to be installed within 168 hours of opening the bag. Unless the
>> approach Pete laid out below works, it seems I need to buy these chips as I
>> need them which might get expensive. The other humidity sensitive part -
>> the LEDs - say they need to be installed within a week. I had no idea
>> some of these parts had the shelf life of lettuce. Is there a local
>> supplier?
>>
>> Thanks again for putting up with my SMD-newbie questions.
>>
>> Chip
>>
>>
>> On Apr 4, 2014, at 6:28 PM, triembed-request at triembed.org wrote:
>>
>> > Send TriEmbed mailing list submissions to
>> > triembed at triembed.org
>> >
>> > To subscribe or unsubscribe via the World Wide Web, visit
>> > http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
>> > or, via email, send a message with subject or body 'help' to
>> > triembed-request at triembed.org
>> >
>> > You can reach the person managing the list at
>> > triembed-owner at triembed.org
>> >
>> > When replying, please edit your Subject line so it is more specific
>> > than "Re: Contents of TriEmbed digest..."
>> >
>> >
>> > Today's Topics:
>> >
>> > 1. Surface Mount Components Newbie Questions (Charles McClelland)
>> > 2. Fwd: Surface Mount Components Newbie Questions (Carl Nobile)
>> > 3. Re: Surface Mount Components Newbie Questions (Carl Nobile)
>> > 4. Re: Surface Mount Components Newbie Questions (Pete Soper)
>> >
>> >
>> > ----------------------------------------------------------------------
>> >
>> > Message: 1
>> > Date: Fri, 4 Apr 2014 16:38:32 -0400
>> > From: Charles McClelland <chip at mcclellands.org>
>> > To: TriEmbed Discussion <triembed at triembed.org>
>> > Subject: [TriEmbed] Surface Mount Components Newbie Questions
>> > Message-ID: <9D001F91-9195-4A64-AD0C-B360E3836CEF at mcclellands.org>
>> > Content-Type: text/plain; charset=us-ascii
>> >
>> > Hey all,
>> >
>> > I am gearing up for my first surface mount project. OSH Park has just
>> told me the boards are in the mail and DigiKey just sent me the bill of
>> materials. I have some questions now that I have opened the box from
>> DigiKey:
>> >
>> > 1) Some of the components claim to be humidity sensitive. Is this a
>> big deal for hobby use? Do I need to keep these in a sealed bag with
>> desiccant or is that overkill?
>> >
>> > 2) Some of the components claim to be sensitive to electrostatic
>> discharge. I have yet to fry a through hold component - are surface mount
>> components more sensitive?
>> >
>> > 3) The components come on tape which will be inefficient to store using
>> the cool storage boxes Pete showed me. Is there anything wrong with
>> removing the parts from the tape?
>> >
>> > I went with 0805 components so nothing is microscopic.
>> >
>> > Thanks,
>> >
>> > Chip
>> >
>> >
>> >
>> >
>> >
>> > ------------------------------
>> >
>> > Message: 2
>> > Date: Fri, 4 Apr 2014 16:55:57 -0400
>> > From: Carl Nobile <carl.nobile at gmail.com>
>> > To: TriEmbed <TriEmbed at triembed.org>
>> > Subject: [TriEmbed] Fwd: Surface Mount Components Newbie Questions
>> > Message-ID:
>> > <CAGQqDQKgkOYCM0U6sC7ynUsT6ykGEVjX6wz=
>> eh71CFDLDkEU2g at mail.gmail.com>
>> > Content-Type: text/plain; charset="utf-8"
>> >
>> > Sorry I sent this to Chip and forgot to click all.
>> >
>> > Chip,
>> >
>> > The static issue is the one to be very careful about. If you walk on a
>> > staticky rug then touch a component, say good by to the component. At
>> the
>> > point where you can feel a shock it is already way too high and will
>> blow
>> > any static sensitive component. They must be kept in one of those dark
>> gray
>> > static bags. DO NOT use the pink ones, they're useless.
>> >
>> > BTW, components do not know if you are a hobbyist or a professional, if
>> the
>> > component doesn't like the humidity it will be damaged in either case.
>> >
>> > I always keep most parts in sealed plastic bags. If static electricity
>> is
>> > not an issue, like with resistors and capacitors, you can use clear
>> plastic
>> > bags. I get them at hobby stores, they come in all the right sizes and
>> are
>> > pretty cheap.
>> >
>> > Carl
>> >
>> >
>> >
>> > On Fri, Apr 4, 2014 at 4:38 PM, Charles McClelland <
>> chip at mcclellands.org>wrote:
>> >
>> >> Hey all,
>> >>
>> >> I am gearing up for my first surface mount project. OSH Park has just
>> >> told me the boards are in the mail and DigiKey just sent me the bill of
>> >> materials. I have some questions now that I have opened the box from
>> >> DigiKey:
>> >>
>> >> 1) Some of the components claim to be humidity sensitive. Is this a
>> big
>> >> deal for hobby use? Do I need to keep these in a sealed bag with
>> desiccant
>> >> or is that overkill?
>> >>
>> >> 2) Some of the components claim to be sensitive to electrostatic
>> >> discharge. I have yet to fry a through hold component - are surface
>> mount
>> >> components more sensitive?
>> >>
>> >> 3) The components come on tape which will be inefficient to store using
>> >> the cool storage boxes Pete showed me. Is there anything wrong with
>> >> removing the parts from the tape?
>> >>
>> >> I went with 0805 components so nothing is microscopic.
>> >>
>> >> Thanks,
>> >>
>> >> Chip
>> >>
>> >>
>> >>
>> >> _______________________________________________
>> >> Triangle, NC Embedded Computing mailing list
>> >> TriEmbed at triembed.org
>> >> http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
>> >> TriEmbed web site: http://TriEmbed.org
>> >>
>> >
>> >
>> >
>> > --
>> >
>> -------------------------------------------------------------------------------
>> > Carl J. Nobile (Software Engineer)
>> > carl.nobile at gmail.com
>> >
>> -------------------------------------------------------------------------------
>> >
>> >
>> >
>> >
>> > --
>> >
>> -------------------------------------------------------------------------------
>> > Carl J. Nobile (Software Engineer)
>> > carl.nobile at gmail.com
>> >
>> -------------------------------------------------------------------------------
>> > -------------- next part --------------
>> > An HTML attachment was scrubbed...
>> > URL: <
>> http://mail.triembed.org/pipermail/triembed_triembed.org/attachments/20140404/ac4b06d5/attachment-0001.html
>> >
>> >
>> > ------------------------------
>> >
>> > Message: 3
>> > Date: Fri, 4 Apr 2014 17:31:48 -0400
>> > From: Carl Nobile <carl.nobile at gmail.com>
>> > To: Charles McClelland <chip at mcclellands.org>, TriEmbed
>> > <TriEmbed at triembed.org>
>> > Subject: Re: [TriEmbed] Surface Mount Components Newbie Questions
>> > Message-ID:
>> > <CAGQqDQ+8g=
>> uXYw7s-9pgBBMcwZ66Fp7y4ZFNs0UV0gBFGUWfpA at mail.gmail.com>
>> > Content-Type: text/plain; charset="utf-8"
>> >
>> > Chip,
>> >
>> > You have a point about the automated machines, if the humidity is high
>> the
>> > machines may malfunction. However, I do know of components that have
>> > humidity issues also like some capacitors. It is not the water itself
>> > which, by-the-way, will not conduct electricity, it's the impurities in
>> the
>> > water that is the issue. Humidity can change a crystal's frequency.
>> When I
>> > used to work on transmitters the oscillators were put into a heated box
>> so
>> > the radio/TV station would not drift off frequency. An FCC pink slip
>> would
>> > show up in the stations mail box with a hefty fine attached if the
>> station
>> > frequency did drift.
>> >
>> > I usually leave the parts on the ribbon tape and fold them up and put
>> them
>> > in a bag. Too much work taking them all apart and getting them mixed up
>> > with other like parts.
>> >
>> > Carl
>> >
>> >
>> >
>> > On Fri, Apr 4, 2014 at 5:14 PM, Charles McClelland <
>> chip at mcclellands.org>wrote:
>> >
>> >> Carl,
>> >>
>> >> Thanks, I guess I do need to think about static. I also like you
>> plastic
>> >> bag idea.
>> >>
>> >> On your point about hobbits or professional, let me explain what I was
>> >> thinking. I assume that the reason many of these components are sold
>> as
>> >> cut tape is to accommodate the hobbyist who wants to order just a few.
>> >> However, I am assuming that these same components are sold in entire
>> reels
>> >> of tape to the professional who might use an automated machine to place
>> >> them on a board as part of a production line process. I guess I was
>> >> wondering if it was the performance of these components in one of these
>> >> automated production lines where humidity is an issue. Otherwise, will
>> >> that sensitivity to humidity be an issue for the component on the
>> assembled
>> >> board?
>> >>
>> >> Thanks,
>> >>
>> >> Chip
>> >>
>> >>
>> >> On Apr 4, 2014, at 4:51 PM, Carl Nobile <carl.nobile at gmail.com> wrote:
>> >>
>> >> Chip,
>> >>
>> >> The static issue is the one to be very careful about. If you walk on a
>> >> staticky rug then touch a component, say good by to the component. At
>> the
>> >> point where you can feel a shock it is already way too high and will
>> blow
>> >> any static sensitive component. They must be kept in one of those dark
>> gray
>> >> static bags. DO NOT use the pink ones, they're useless.
>> >>
>> >> BTW, components do not know if you are a hobbyist or a professional, if
>> >> the component doesn't like the humidity it will be damaged in either
>> case.
>> >>
>> >> I always keep most parts in sealed plastic bags. If static electricity
>> is
>> >> not an issue, like with resistors and capacitors, you can use clear
>> plastic
>> >> bags. I get them at hobby stores, they come in all the right sizes and
>> are
>> >> pretty cheap.
>> >>
>> >> Carl
>> >>
>> >>
>> >>
>> >> On Fri, Apr 4, 2014 at 4:38 PM, Charles McClelland <
>> chip at mcclellands.org>wrote:
>> >>
>> >>> Hey all,
>> >>>
>> >>> I am gearing up for my first surface mount project. OSH Park has just
>> >>> told me the boards are in the mail and DigiKey just sent me the bill
>> of
>> >>> materials. I have some questions now that I have opened the box from
>> >>> DigiKey:
>> >>>
>> >>> 1) Some of the components claim to be humidity sensitive. Is this a
>> big
>> >>> deal for hobby use? Do I need to keep these in a sealed bag with
>> desiccant
>> >>> or is that overkill?
>> >>>
>> >>> 2) Some of the components claim to be sensitive to electrostatic
>> >>> discharge. I have yet to fry a through hold component - are surface
>> mount
>> >>> components more sensitive?
>> >>>
>> >>> 3) The components come on tape which will be inefficient to store
>> using
>> >>> the cool storage boxes Pete showed me. Is there anything wrong with
>> >>> removing the parts from the tape?
>> >>>
>> >>> I went with 0805 components so nothing is microscopic.
>> >>>
>> >>> Thanks,
>> >>>
>> >>> Chip
>> >>>
>> >>>
>> >>>
>> >>> _______________________________________________
>> >>> Triangle, NC Embedded Computing mailing list
>> >>> TriEmbed at triembed.org
>> >>> http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
>> >>> TriEmbed web site: http://TriEmbed.org <http://triembed.org/>
>> >>>
>> >>
>> >>
>> >>
>> >> --
>> >>
>> >>
>> -------------------------------------------------------------------------------
>> >> Carl J. Nobile (Software Engineer)
>> >> carl.nobile at gmail.com
>> >>
>> -------------------------------------------------------------------------------
>> >>
>> >>
>> >>
>> >>
>> >
>> >
>> > --
>> >
>> -------------------------------------------------------------------------------
>> > Carl J. Nobile (Software Engineer)
>> > carl.nobile at gmail.com
>> >
>> -------------------------------------------------------------------------------
>> > -------------- next part --------------
>> > An HTML attachment was scrubbed...
>> > URL: <
>> http://mail.triembed.org/pipermail/triembed_triembed.org/attachments/20140404/b42fbaee/attachment-0001.html
>> >
>> >
>> > ------------------------------
>> >
>> > Message: 4
>> > Date: Fri, 04 Apr 2014 18:28:33 -0400
>> > From: Pete Soper <pete at soper.us>
>> > To: triembed at triembed.org
>> > Subject: Re: [TriEmbed] Surface Mount Components Newbie Questions
>> > Message-ID: <533F3211.8000906 at soper.us>
>> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>> >
>> > I leave those chips in their bags. Inside with the chips are bags of
>> > desiccants. I'm told that the basic issue is that if the chip absorbs
>> > much moisture then when it goes through the reflow oven it can
>> > "popcorn." I don't need to describe what that means. I leave chips like
>> > this in the bags, then when I'm going to use a fraction of them I put
>> > the remainder with the desiccant bags into airtight containers with the
>> > humidity test strips. This may be overkill.
>> >
>> > And as I type this I'm about to test out the low tech hood and vent
>> > system for my oven. This is a very small oven and I have a very powerful
>> > fan pushing air out of the basement, so hopefully I won't have to run
>> > the oven outdoors in the near future.
>> > -Pete
>> >
>> > On 04/04/2014 04:38 PM, Charles McClelland wrote:
>> >> Hey all,
>> >>
>> >> I am gearing up for my first surface mount project. OSH Park has just
>> told me the boards are in the mail and DigiKey just sent me the bill of
>> materials. I have some questions now that I have opened the box from
>> DigiKey:
>> >>
>> >> 1) Some of the components claim to be humidity sensitive. Is this a
>> big deal for hobby use? Do I need to keep these in a sealed bag with
>> desiccant or is that overkill?
>> >>
>> >> 2) Some of the components claim to be sensitive to electrostatic
>> discharge. I have yet to fry a through hold component - are surface mount
>> components more sensitive?
>> >>
>> >> 3) The components come on tape which will be inefficient to store
>> using the cool storage boxes Pete showed me. Is there anything wrong with
>> removing the parts from the tape?
>> >>
>> >> I went with 0805 components so nothing is microscopic.
>> >>
>> >> Thanks,
>> >>
>> >> Chip
>> >>
>> >>
>> >>
>> >> _______________________________________________
>> >> Triangle, NC Embedded Computing mailing list
>> >> TriEmbed at triembed.org
>> >> http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
>> >> TriEmbed web site: http://TriEmbed.org
>> >
>> >
>> >
>> >
>> > ------------------------------
>> >
>> > Subject: Digest Footer
>> >
>> > _______________________________________________
>> > TriEmbed mailing list
>> > TriEmbed at triembed.org
>> > http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
>> >
>> >
>> > ------------------------------
>> >
>> > End of TriEmbed Digest, Vol 11, Issue 6
>> > ***************************************
>>
>>
>> _______________________________________________
>> Triangle, NC Embedded Computing mailing list
>> TriEmbed at triembed.org
>> http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
>> TriEmbed web site: http://TriEmbed.org
>>
>
>
>
> --
>
> -------------------------------------------------------------------------------
> Carl J. Nobile (Software Engineer)
> carl.nobile at gmail.com
> -------------------------------------------------------------------------------
>
>
> _______________________________________________
> TriEmbed mailing list
> TriEmbed at triembed.org
> http://mail.triembed.org/mailman/listinfo/triembed_triembed.org
>
>
--
Martin Brooke
--
*Martin Brooke*
Associate Professor,
and Philip Baugh Scholar
Department of Electrical and Computer Engineering <http://www.ee.duke.edu>
Box 90291
Duke University <http://www.duke.edu/>
Durham, NC 27708-0291
*Phone:* (919) 660-5504
*Secretary:* (919)-660-5252
*Fax:* (919)-660-5293
*E-Mail:* mbrooke at ee.duke.edu
*Office:*
3581 FCIEMAS Building
3rd Floor South Wing
Duke University
Durham, NC 27708
*Physical Delivery Address:*
Department of Electrical and Computer Engineering
130 Hudson Hall
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Durham, NC 27708
Phone: (919)-660-5252
[Home] <http://www.ee.duke.edu/%7Embrooke/index.html>[Academic<http://www.ee.duke.edu/%7Embrooke/00courses.html>
] [Research] <http://www.ee.duke.edu/%7Embrooke/00research.html>[
Publications <http://www.ee.duke.edu/%7Embrooke/Papers.html>]
[More...]<http://www.ee.duke.edu/%7Embrooke/my_index.html>
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