sci.electronics.repair - 25 new messages in 8 topics - digest

sci.electronics.repair
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Today's topics:

==============================================================================
TOPIC: OT--Actual electronics repair question
http://groups.google.com/group/sci.electronics.repair/t/1c7563aead5e20a6?hl=en
==============================================================================

== 1 of 4 ==
Date: Sat, Jan 15 2011 1:25 pm
From: Jeff Liebermann

On Sat, 15 Jan 2011 20:54:48 +0000 (UTC), Meat Plow
<mhywatt@yahoo.com> wrote:

>I think it stores in erasable prom but can't be sure. I had it open once
>and don't recall seeing anything big enough to be a supercap or battery.
>It's really miniaturized.

I'm too lazy to dig out the schematic, but I guess(tm) it's NVRAM of
some sort. I don't see a coin cell inside. Some inside photos:
<http://www.mods.dk/picture.php?brandid=7&model=vx-5r>
Registration required to see them full size.

Note the big white circle that is silk screen to the PCB. That's
where the speaker magnet is positioned. I suspect that if you place
some foam tape to put some pressure on the PCB, it might reduce the
microphonics.

Also, two reasons it's only on 440Mhz. It might be a seperate VCO
oscillator for each band, and the LO multiplier ratio is higher for
440 than for the other bands.

Incidentally, I sorta blundered across this BNC to SMA adapter made
specifically for various Yaesu handhelds. Looks better than the
easily broken adapters I've been using.
<http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=350298285336>
There a bunch of others with similar design available.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

== 2 of 4 ==
Date: Sat, Jan 15 2011 2:57 pm
From: Meat Plow

On Sat, 15 Jan 2011 21:13:39 +0000, Baron wrote:

> Meat Plow Inscribed thus:
>
>> On Sat, 15 Jan 2011 17:43:05 +0000, Baron wrote:
>>
>>> Jeff Liebermann Inscribed thus:
>>>
>>>> On Thu, 13 Jan 2011 21:37:02 +0000 (UTC), Meat Plow
>>>> <mhywatt@yahoo.com> wrote:
>>>>
>>>>>No, tapping on it will not induce micro-phonics but will often lessen
>>>>>the howl.
>>>>
>>>> Well, if it were "grounding", then banging on the case would have no
>>>> effect (unless there were some screws loose).
>>>>
>>>> Incidentally, I tried my VX-5 turn on/off times. It took about 1
>>>> second to turn on, and the same to turn off. Pushing the button to
>>>> turn off was *NOT* instantaneous. I had to hold it for 1 sec. It's
>>>> been like that since new, so there's been no deterioration. At this
>>>> point, I don't know if it's a firmware issue, settings issue, or
>>>> dirty
>>>> keyboard. Save, reset and reload seems the easiest to do first.
>>>>
>>>>>Once the radio is on, the howl goes away, maybe after 10 minutes.
>>>>
>>>> Something is getting warm perhaps?
>>>>
>>>>>We have it here due to severe thunderstorms with large hail, damaging
>>>>>winds, localized flooding, micro-bursts and tornadoes.
>>>>
>>>> That's why I like California. Other than earthquakes and government,
>>>> we don't have much in the way to disasters here.
>>>>
>>>>>... I had just purchased a Dodge 4x4 in the spring. I was out chasing
>>>>>a storm around and got pelted by some golf ball sized hail. That
>>>>>ended my chasing days. I don't have a beater that I care about
>>>>>looking like someone took a hammer to it.
>>>>
>>>> Ouch. I've never even seen a tornado, so I have no idea what it
>>>> might
>>>> be like. Raining golf balls sounds like no fun. Yes, Skywarn has
>>>> its place in your part of the country.
>>>>
>>>>
>>> This thing doesn't have a backup battery does it ? If so have you
>>> replaced it !
>>
>> I think it stores in erasable prom but can't be sure. I had it open
>> once and don't recall seeing anything big enough to be a supercap or
>> battery. It's really miniaturized.
>>
>>
> A friend of mine had a HT, Icom I think, with a 2021 battery in it. It
> went bananas changing channels when you pressed TX. Turned out that the
> battery was the problem. Now I don't know whether it was low voltage or
> corrosion because it was repaired by the supplier.
>
> Sadly he's now silent key, so I can't go and ask him. Come to think
> about it my FT290 has a battery in it... I'll have to check that !

I'll have another look when I pull it apart to clean the conductive pad
on the power button. I'm sure there are no 3 volt lithium cells in it in
the 20xx size.

--
Live Fast, Die Young and Leave a Pretty Corpse

== 3 of 4 ==
Date: Sat, Jan 15 2011 3:10 pm
From: Meat Plow

On Sat, 15 Jan 2011 13:25:29 -0800, Jeff Liebermann wrote:

> On Sat, 15 Jan 2011 20:54:48 +0000 (UTC), Meat Plow <mhywatt@yahoo.com>
> wrote:
>
>>I think it stores in erasable prom but can't be sure. I had it open once
>>and don't recall seeing anything big enough to be a supercap or battery.
>>It's really miniaturized.
>
> I'm too lazy to dig out the schematic, but I guess(tm) it's NVRAM of
> some sort. I don't see a coin cell inside. Some inside photos:
> <http://www.mods.dk/picture.php?brandid=7&model=vx-5r> Registration
> required to see them full size.

Yeah I got the schematic around somewhere, to lazy to dig it up.

> Note the big white circle that is silk screen to the PCB. That's where
> the speaker magnet is positioned. I suspect that if you place some foam
> tape to put some pressure on the PCB, it might reduce the microphonics.

I think i read that suggestion a long time ago too.

> Also, two reasons it's only on 440Mhz. It might be a seperate VCO
> oscillator for each band, and the LO multiplier ratio is higher for 440
> than for the other bands.

Understood.

> Incidentally, I sorta blundered across this BNC to SMA adapter made
> specifically for various Yaesu handhelds. Looks better than the easily
> broken adapters I've been using.
> <http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=350298285336> There
> a bunch of others with similar design available.

Yeah I have a couple SMA - BNC adapters. Bought them at a ham fest a good
while back. If you are going to use the SMA with an external antenna in
your home or vehicle they make an adaptor with coax inbetween connectors.
I have one that has an SMA on one end, a couple feet of very thing 50 ohm
coax (not sure the number but it's half as thin or more as RG58/U) and a
SO239 on the other. Beats using a BNC - SO239 adapter.

--
Live Fast, Die Young and Leave a Pretty Corpse

== 4 of 4 ==
Date: Sat, Jan 15 2011 9:25 pm
From: "Michael A. Terrell"

Meat Plow wrote:
>
> On Sat, 15 Jan 2011 13:25:29 -0800, Jeff Liebermann wrote:
>
> > On Sat, 15 Jan 2011 20:54:48 +0000 (UTC), Meat Plow <mhywatt@yahoo.com>
> > wrote:
> >
> >>I think it stores in erasable prom but can't be sure. I had it open once
> >>and don't recall seeing anything big enough to be a supercap or battery.
> >>It's really miniaturized.
> >
> > I'm too lazy to dig out the schematic, but I guess(tm) it's NVRAM of
> > some sort. I don't see a coin cell inside. Some inside photos:
> > <http://www.mods.dk/picture.php?brandid=7&model=vx-5r> Registration
> > required to see them full size.
>
> Yeah I got the schematic around somewhere, to lazy to dig it up.
>
> > Note the big white circle that is silk screen to the PCB. That's where
> > the speaker magnet is positioned. I suspect that if you place some foam
> > tape to put some pressure on the PCB, it might reduce the microphonics.
>
> I think i read that suggestion a long time ago too.
>
> > Also, two reasons it's only on 440Mhz. It might be a seperate VCO
> > oscillator for each band, and the LO multiplier ratio is higher for 440
> > than for the other bands.
>
> Understood.
>
> > Incidentally, I sorta blundered across this BNC to SMA adapter made
> > specifically for various Yaesu handhelds. Looks better than the easily
> > broken adapters I've been using.
> > <http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=350298285336> There
> > a bunch of others with similar design available.
>
> Yeah I have a couple SMA - BNC adapters. Bought them at a ham fest a good
> while back. If you are going to use the SMA with an external antenna in
> your home or vehicle they make an adaptor with coax inbetween connectors.
> I have one that has an SMA on one end, a couple feet of very thing 50 ohm
> coax (not sure the number but it's half as thin or more as RG58/U) and a
> SO239 on the other. Beats using a BNC - SO239 adapter.

RG-174?

--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.

==============================================================================
TOPIC: AA-sized conductor (fake battery) wanted
http://groups.google.com/group/sci.electronics.repair/t/33083a4b1e46ccc0?hl=en
==============================================================================

== 1 of 4 ==
Date: Sat, Jan 15 2011 1:46 pm
From: D Yuniskis

On 1/15/2011 2:20 PM, Baron wrote:
> D Yuniskis Inscribed thus:
>
>> On 1/15/2011 10:46 AM, Baron wrote:
>>>> My comment was intended more as "tongue-in-cheek" (I have a
>>>> friend that I *never* ask for things like this as he *would*
>>>> turn something on a lathe for me and I often end up embarassed
>>>> at the "excessive quality" of his solution! :> )
>>>
>>> Us mechanical engineer types take great pride in our hobbies ! :-)
>>
>> Well, *he's* the mechanical type: lathe, end mill, surface grinder,
>> shadow graph, coil winder, etc.
>>
>> Of course, another friend has a sinker EDM and a couple of wire EDM
>> machines... a bit too expensive to qualify as "toys" :-/
>
> Ooo ! I feel the green eyed monster coming on. :-)

Yeah, when I hear complaints about all of my crap ^H^H^H er, *toys*,
I think about *these* sorts of things! :> The first friend (above)
gave me a 3KW FERRUPS (UPS) one day. I was trying to figure out how
to get it *into* the truck (weighed a couple hundred pounds... the
batteries alone weighed more than 100 pounds). He "disappeared".
And came back a few minutes later with a front-end loader, scooped
the UPS into the bucket and dropped it onto the truck.

Sheesh!

>>>> Some batteries (against which the "dummy" may mate) require
>>>> the little "nub" on the + end to ensure contact. Likewise,
>>>> some battery holders "guard" the + terminal with a bit of
>>>> raised plastic to protect against a battery installed backwards.
>>>> (i.e., a "flat surface" -- like the - terminal -- won't connect)
>>>
>>> Ah ! In that case you would need to turn it to produce the pip on one
>>> end.
>>
>> Yes, that was why I suggested the lathe instead of just cutting drill
>> rod, etc.
>
> I wasn't aware of that limitation. Though my son just pointed out the
> battery holder in the Wii was shaped so you couldn't put the battery in
> backwards.

Yes. It's the same sort of problem you face with "untabbed"
NiCd or Li cells. They don't always want to conduct abutted
"end to end".

>> Though, with copper, I think you could *almost* use a file as "cutting
>> tool" and a large electric (hand) drill to spin the work. Wouldn't
>> have much control over the dimension of the pip but I suspect you
>> could fashion a functional one in a few minutes. Heck, even putting a
>> slight taper on the one end would work!
>
> Very true ! A trick I've used to clean up the end of damaged bolts.

== 2 of 4 ==
Date: Sat, Jan 15 2011 9:28 pm
From: "Michael A. Terrell"

Baron wrote:
>
> Very true ! A trick I've used to clean up the end of damaged bolts.

How rebolting! ;-)

--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.

== 3 of 4 ==
Date: Sat, Jan 15 2011 9:53 pm
From: Baron

D Yuniskis Inscribed thus:

> On 1/15/2011 2:20 PM, Baron wrote:
>> D Yuniskis Inscribed thus:
>>
>>> On 1/15/2011 10:46 AM, Baron wrote:
>>>>> My comment was intended more as "tongue-in-cheek" (I have a
>>>>> friend that I *never* ask for things like this as he *would*
>>>>> turn something on a lathe for me and I often end up embarassed
>>>>> at the "excessive quality" of his solution! :> )
>>>>
>>>> Us mechanical engineer types take great pride in our hobbies ! :-)
>>>
>>> Well, *he's* the mechanical type: lathe, end mill, surface grinder,
>>> shadow graph, coil winder, etc.
>>>
>>> Of course, another friend has a sinker EDM and a couple of wire EDM
>>> machines... a bit too expensive to qualify as "toys" :-/
>>
>> Ooo ! I feel the green eyed monster coming on. :-)
>
> Yeah, when I hear complaints about all of my crap ^H^H^H er, *toys*,
> I think about *these* sorts of things! :> The first friend (above)
> gave me a 3KW FERRUPS (UPS) one day. I was trying to figure out how
> to get it *into* the truck (weighed a couple hundred pounds... the
> batteries alone weighed more than 100 pounds). He "disappeared".
> And came back a few minutes later with a front-end loader, scooped
> the UPS into the bucket and dropped it onto the truck.
>
> Sheesh!

Indeed. :-) In my case it would still be in the truck.

>>>>> Some batteries (against which the "dummy" may mate) require
>>>>> the little "nub" on the + end to ensure contact. Likewise,
>>>>> some battery holders "guard" the + terminal with a bit of
>>>>> raised plastic to protect against a battery installed backwards.
>>>>> (i.e., a "flat surface" -- like the - terminal -- won't connect)
>>>>
>>>> Ah ! In that case you would need to turn it to produce the pip on
>>>> one end.
>>>
>>> Yes, that was why I suggested the lathe instead of just cutting
>>> drill rod, etc.
>>
>> I wasn't aware of that limitation. Though my son just pointed out
>> the battery holder in the Wii was shaped so you couldn't put the
>> battery in backwards.
>
> Yes. It's the same sort of problem you face with "untabbed"
> NiCd or Li cells. They don't always want to conduct abutted
> "end to end".
>
>>> Though, with copper, I think you could *almost* use a file as
>>> "cutting
>>> tool" and a large electric (hand) drill to spin the work. Wouldn't
>>> have much control over the dimension of the pip but I suspect you
>>> could fashion a functional one in a few minutes. Heck, even putting
>>> a slight taper on the one end would work!
>>
>> Very true ! A trick I've used to clean up the end of damaged bolts.

--
Best Regards:
Baron.

== 4 of 4 ==
Date: Sat, Jan 15 2011 9:56 pm
From: David Nebenzahl

On 1/15/2011 9:28 PM Michael A. Terrell spake thus:

> Baron wrote:
>>
>> Very true ! A trick I've used to clean up the end of damaged bolts.
>
> How rebolting! ;-)

Aaaaaah, the guy's nuts I say. Cross-threaded between the ears. Tapped
out, ready to die.

--
Comment on quaint Usenet customs, from Usenet:

To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.

==============================================================================
TOPIC: Magnifying glass for smd components
http://groups.google.com/group/sci.electronics.repair/t/152fab9f5593225c?hl=en
==============================================================================

== 1 of 5 ==
Date: Sat, Jan 15 2011 1:54 pm
From: D Yuniskis

On 1/15/2011 2:27 PM, Baron wrote:
> D Yuniskis Inscribed thus:
>
>> On 1/15/2011 2:08 PM, Jeff Liebermann wrote:
>>> However, that's not what I use on the bench. I butchered a USB
>>> camera and what's left of a childrens microscope into a nifty
>>> magnifying
>>> system. The LCD monitor displays the image and the computah can
>>> capture the image if necessary. I suggest you just play with
>>> whatever lenses you can scrounge and a USB camera and see what you
>>> can do.
>>
>> I have a USB camera mounted on a gooseneck (manual focus) that
>> I can position over (one of) the stereoscope's eyepiece. Or,
>> use "unaided" to just examine boards/components. I can;t recall
>> who makes it -- it was from a "science" classroom intended to
>> let students examine bugs, minerals, anything under a microscope,
>> etc. I.e., *designed* for this sort of purpose (instead of as
>> a "web cam")
>
> Veho ! Maybe !

<frown> I did a quick google.images and didn't see anything that looked
like what I have. The gooseneck is *really* long. I.e., with the
base sitting on the table, the gooseneck extends high enough to get
*above* the stereoscope. Stereoscope is a minimum of 12" above the
table (in the full "down" position). Gooseneck easily reaches 18"
above the table (if you want the camera pointed *down* -- higher
if you can tolerate the camera pointed "sideways"... since the
gooseneck wouldn't have to double back on itself)

I'm in the middle of packing for a trip but will try to remember to
drag the camera out (it sits behind my LCD monitors and peeks *over*
them so it isn't easily accessible without moving stuff) and see
what the make/model is.

== 2 of 5 ==
Date: Sat, Jan 15 2011 1:57 pm
From: "N_Cook"

Baron <baron.nospam@linuxmaniac.nospam.net> wrote in message
news:igt358$gkj$2@news.eternal-september.org...
> D Yuniskis Inscribed thus:
>
> > On 1/15/2011 10:52 AM, Baron wrote:
> >> D Yuniskis Inscribed thus:
> >>> I have found that adequate *light* is more important than
> >>> magnification (but that may just be the age of my eyes)
> >>
> >> I can certainly empathise with that last paragraph. Good lighting is
> >> very important. Particularly where identifying colors is required.
> >
> > I find that I need more than "good" :-/
> >
> > I used to be able to read the markings on DIPs at arm's length
> > "with a glance". Now, I need to rock them back and forth to get
> > the light to reflect off them at the right angle before things
> > are visible (at times, I swear they have changed to BLACK INK!! :< )
> >
> > Ditto for color codes. Seems like the colors have crept closer
> > together in the spectrum :-/
>
> Yes colours have definitely become harder to read. I've used the "PTFE"
> tape trick on IC's and SMD parts a number of times to read the
> markings.
>
> --
> Best Regards:
> Baron.

Shame I didn't patent that PTFE tip

== 3 of 5 ==
Date: Sat, Jan 15 2011 2:03 pm
From: "N_Cook"

Jeff Liebermann <jeffl@cruzio.com> wrote in message
news:2a14j6l982bbcbfofbrf9a6bug1rub9vv4@4ax.com...
> On Fri, 14 Jan 2011 15:22:26 -0800 (PST), Jack00 <SPal508596@aol.com>
> wrote:
>
> >Does anyone know a magnifying glass that can be used for surface
> >mounted components as they are too small to see with a standard
> >magnifying glass. And also which amplification ie 2x 5x 10x 20x
>
> There are plenty of optical instruments, microsocopes, and magnifiers
> that can be used. For portable use, I have a small 10x pocket
> magnifier I bought somewhere. Overchoice:
> <http://www.pocketmagnifying.com>
>
> However, that's not what I use on the bench. I butchered a USB camera
> and what's left of a childrens microscope into a nifty magnifying
> system. The LCD monitor displays the image and the computah can
> capture the image if necessary. I suggest you just play with whatever
> lenses you can scrounge and a USB camera and see what you can do.
>
> What I use in my office is rather disgusting. I have a Luxo
> magnifying lamp on the bench. The circular fluorescent light provides
> really nice lighting. I put on a pair of 3 diopeter commodity
> eyeglasses and shove my face up against the glass lens. I don't know
> what magnification that offers, but it's good enough for all but the
> smallest components. If I want more power, I have an Olympus BH
> microscope.
>
> Incidentally, I have a small camera ty-wrapped to my soldering iron.
> The depth of field sucks, but it's amazingly useful once I retrained
> myself to look at the screen and not at the work.
>
> You can buy such USB microscope cameras on eBay or various web sites.
> Just search for "USB microscope". Most of them are 100x to 400x but
> there are a few with lower power or with zoom. For example, 10x to
> 200x:
> <http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=110499624122>
>
>
>
> --
> Jeff Liebermann jeffl@cruzio.com
> 150 Felker St #D http://www.LearnByDestroying.com
> Santa Cruz CA 95060 http://802.11junk.com
> Skype: JeffLiebermann AE6KS 831-336-2558

I'll have to look into making a soldering-iron tip viewer , trying to use a
soldering iron under an illuminated inspection lamp can be a pain in some
circumstances.

== 4 of 5 ==
Date: Sat, Jan 15 2011 7:53 pm
From: Jeff Liebermann

On Sat, 15 Jan 2011 21:23:48 +0000, Baron
<baron.nospam@linuxmaniac.nospam.net> wrote:

>Yes colours have definitely become harder to read. I've used the "PTFE"
>tape trick on IC's and SMD parts a number of times to read the
>markings.

I often use my pocket LED flashing to provide extra illumination. It
has a built in holder, also known as my teeth.

So, what's the PTFE trick for reading IC and SMD markings? I couldn't
find anything with Google.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

== 5 of 5 ==
Date: Sat, Jan 15 2011 9:58 pm
From: Baron

Jeff Liebermann Inscribed thus:

> On Sat, 15 Jan 2011 21:23:48 +0000, Baron
> <baron.nospam@linuxmaniac.nospam.net> wrote:
>
>>Yes colours have definitely become harder to read. I've used the
>>"PTFE" tape trick on IC's and SMD parts a number of times to read the
>>markings.
>
> I often use my pocket LED flashing to provide extra illumination. It
> has a built in holder, also known as my teeth.
>
> So, what's the PTFE trick for reading IC and SMD markings? I couldn't
> find anything with Google.
>
Place a short length of plumbers ptfe tape over the surface and rub with
your fingernail.

--
Best Regards:
Baron.

==============================================================================
TOPIC: A minor repair success...
http://groups.google.com/group/sci.electronics.repair/t/7fb8df5d4210df9c?hl=en
==============================================================================

== 1 of 8 ==
Date: Sat, Jan 15 2011 4:25 pm
From: Jeffrey Angus

Wife hands me the DVD player from the bedroom, "It
won't turn on anymore."

Aw crap, well, ok, I'll look at it.

Take it out the the shop, pop the lid, oh look, a
bulging cap in the switching power supply. Replace
that and presto, it works again.

Sometimes we get lucky.

And I'll get dinner tonight. ;-)

Jeff

== 2 of 8 ==
Date: Sat, Jan 15 2011 4:51 pm
From: Meat Plow

On Sat, 15 Jan 2011 18:25:53 -0600, Jeffrey Angus wrote:

> Wife hands me the DVD player from the bedroom, "It won't turn on
> anymore."
>
> Aw crap, well, ok, I'll look at it.
>
> Take it out the the shop, pop the lid, oh look, a bulging cap in the
> switching power supply. Replace that and presto, it works again.
>
> Sometimes we get lucky.
>
> And I'll get dinner tonight. ;-)
>
> Jeff

So if you didn't fix the DVD player no dinner?

--
Live Fast, Die Young and Leave a Pretty Corpse

== 3 of 8 ==
Date: Sat, Jan 15 2011 5:38 pm
From: Sergey Kubushyn

Meat Plow <mhywatt@yahoo.com> wrote:
> On Sat, 15 Jan 2011 18:25:53 -0600, Jeffrey Angus wrote:
>
>> Wife hands me the DVD player from the bedroom, "It won't turn on
>> anymore."
>>
>> Aw crap, well, ok, I'll look at it.
>>
>> Take it out the the shop, pop the lid, oh look, a bulging cap in the
>> switching power supply. Replace that and presto, it works again.
>>
>> Sometimes we get lucky.
>>
>> And I'll get dinner tonight. ;-)
>>
>> Jeff
>
> So if you didn't fix the DVD player no dinner?

No guts no glory :)

---
******************************************************************
* KSI@home KOI8 Net < > The impossible we do immediately. *
* Las Vegas NV, USA < > Miracles require 24-hour notice. *
******************************************************************

== 4 of 8 ==
Date: Sat, Jan 15 2011 6:04 pm
From: Jeffrey Angus

On 1/15/2011 6:51 PM, Meat Plow wrote:
> On Sat, 15 Jan 2011 18:25:53 -0600, Jeffrey Angus wrote:
>> Sometimes we get lucky.
>>
>> And I'll get dinner tonight. ;-)
>>
>> Jeff
>
> So if you didn't fix the DVD player no dinner?

Well that depends....

If I had said, "Nope, the DVD is broke, it died. We need
to buy a new one for $19.95"

I would probably still have gotten dinner.

If I had said, "You've got to be kidding me? Why should
I waste my time on that cheap piece of shit?"

I would have been eating an MRE out in the garage.

Jeff

== 5 of 8 ==
Date: Sat, Jan 15 2011 6:45 pm
From: D Yuniskis

On 1/15/2011 5:25 PM, Jeffrey Angus wrote:
> Wife hands me the DVD player from the bedroom, "It
> won't turn on anymore."
>
> Aw crap, well, ok, I'll look at it.
>
> Take it out the the shop, pop the lid, oh look, a
> bulging cap in the switching power supply. Replace
> that and presto, it works again.
>
> Sometimes we get lucky.

You might want to actually *check* the voltage across that cap
instead of blindly replacing it with one that has the same
markings. I see lots of undervoltage caps in cheapy consumer
kit (especially DVD players).

> And I'll get dinner tonight. ;-)

Yeah, but will it be *edible*?? :>

== 6 of 8 ==
Date: Sat, Jan 15 2011 6:45 pm
From: Jeffrey Angus

On 1/15/2011 8:45 PM, D Yuniskis wrote:
> You might want to actually *check* the voltage across that cap
> instead of blindly replacing it with one that has the same
> markings. I see lots of undervoltage caps in cheapy consumer
> kit (especially DVD players).

Oh that was easy, it was a 16V cap. I replaced it with a 25V
just on general principles.
>
>> And I'll get dinner tonight. ;-)
>
> Yeah, but will it be *edible*?? :>

It was quite good actually.

Jeff

== 7 of 8 ==
Date: Sat, Jan 15 2011 8:07 pm
From: Jeff Liebermann

On Sat, 15 Jan 2011 18:25:53 -0600, Jeffrey Angus
<jangus@suddenlink.net> wrote:

>And I'll get dinner tonight. ;-)

Electrolytic capacitors for dinner is a rather sparce and toxic diet.
You had it easy. I just tore apart (formerly known as disassembled)
an iPhone first degeneration. As it was designed to do, the battery
leaked slimy goo and corrosive slime all over the antenna section and
parts of my workbench. If I get it working and sold, I can afford
several lavish dinners for two. Eat your heart out (literally).

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

== 8 of 8 ==
Date: Sat, Jan 15 2011 9:33 pm
From: "Michael A. Terrell"

Jeffrey Angus wrote:
>
> On 1/15/2011 6:51 PM, Meat Plow wrote:
> > On Sat, 15 Jan 2011 18:25:53 -0600, Jeffrey Angus wrote:
> >> Sometimes we get lucky.
> >>
> >> And I'll get dinner tonight. ;-)
> >>
> >> Jeff
> >
> > So if you didn't fix the DVD player no dinner?
>
> Well that depends....
>
> If I had said, "Nope, the DVD is broke, it died. We need
> to buy a new one for $19.95"
>
> I would probably still have gotten dinner.
>
> If I had said, "You've got to be kidding me? Why should
> I waste my time on that cheap piece of shit?"
>
> I would have been eating an MRE out in the garage.

Or some Spam at the General Store...

--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.

==============================================================================
TOPIC: Digital Volume Controls
http://groups.google.com/group/sci.electronics.repair/t/215bd1b40b7247b6?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Jan 15 2011 6:14 pm
From: William Brown

I was told to totally remove the grease as this has leaked out from the
spindle, but not my theory.

So is it OK for the contacts to run dry or should they be lubricated
with CRC 2.26 or ELECTROLUBE EML.

Thanks

==============================================================================
TOPIC: Samsung Monitor
http://groups.google.com/group/sci.electronics.repair/t/b8e64ece9d65ce8d?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Jan 15 2011 6:16 pm
From: William Brown

I have a LS19MEDSBQ/XSA

How do you remove the back..

Thanks

==============================================================================
TOPIC: Electronic curiosities
http://groups.google.com/group/sci.electronics.repair/t/92fb1a53d8547e80?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Jan 15 2011 7:47 pm
From: David Nebenzahl

Trying to teach myself electronics, I've been reading a few textbooks I
inherited on the subject. Tough going, as my math is in serious need of
repair.

Anyhow, found a couple of interesting things in these older books:

1. TRF:

In the section on modulation, demodulation and other radio-related stuff
one book brings up "the tuned radio-frequency receiver" before
discussing superhet, as one would expect. But they say;

During the evolution of radio, the tuned-radio-frequency (TRF)
receiver was used to receive AM signals. Today, a few special
applications still use TRF receivers.

Now, they go on to explain why TRF is inferior to superheterodyne. But
I'm curious: are there still any radios that use TRF? and why? (Keep in
mind this book was written in 1979).

2. Thermionic converters & magneto-hydrodynamic generators:

Another book (which I frankly don't like as much since it's so
math-heavy: wouldn't electronics be so easy to learn if all that goddamn
math didn't get in the way?) covers these somewhat fantastic devices in
its chapter on "Energy Conversion Phenomena". The thermionic converter
is especially intriguing, as it seems a fairly efficient (20%) direct
conversion from heat to electricity. I seem to remember seeing a program
on PBS about something like magnetohydrodynamics being developed for
deep-space exploration propulsion.

Are either of these devices being seriously researched or used nowadays?
Keep in mind that *this* book was written in 1966.

--
Comment on quaint Usenet customs, from Usenet:

To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.

==============================================================================
TOPIC: PC PSU Component Value (TH1)
http://groups.google.com/group/sci.electronics.repair/t/8484746dd62b9840?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Jan 15 2011 9:10 pm
From: Bob Villa

On Jan 15, 7:23 am, "Michael Kennedy" <m...@nospam.com> wrote:
> "Bob Villa" <pheeh.z...@gmail.com> wrote in message
>
> news:5536bca2-513d-4008-9290-a7d6ca63a209@k3g2000yqc.googlegroups.com...
> On Jan 13, 5:52 am, Bob Villa <pheeh.z...@gmail.com> wrote:
>
> > Would anyone know the value or an equivalent for "TH1" on a CoolMax
> > PSU? (CA-400)
> > TIA
> > bob_v
>
> Can you give some sort of description of the componenet?
>
> By the way, are you really Bob Vila?
>
> --
>
> Mike

No, Roberto...Poncho's great-great-grandson!
I believe it to be a thermistor near the fuse. (I haven't taken it out
to see any markings)

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sci.electronics.repair - 25 new messages in 8 topics - digest

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