sci.electronics.repair@googlegroups.com

Today's topics:

* OT Using Mozilla T-Bird on here ... - 4 messages, 4 authors
http://groups.google.com/group/sci.electronics.repair/t/ab7978b76cb06599?hl=en
* OT: archiving on CD/DVD - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/7865cc1a1f8d8699?hl=en
* Unlabelled and disconnected mains primary wires - 4 messages, 4 authors
http://groups.google.com/group/sci.electronics.repair/t/827164e09c1645bf?hl=en
* Lead free solder - 2 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/23523e78c578fbf8?hl=en
* IC-28A transmit section carnage - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/2d64dac1e201e106?hl=en
* 40Gb Western Digital hard drive - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/d11c27dd9c7d80c0?hl=en
* DTV decoder repair, capacitor gets too hot - 2 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/2a64f4c6ccba41cd?hl=en

==============================================================================
TOPIC: OT Using Mozilla T-Bird on here ...
http://groups.google.com/group/sci.electronics.repair/t/ab7978b76cb06599?hl=en
==============================================================================

== 1 of 4 ==
Date: Tues, Jun 1 2010 10:37 am
From: UCLAN

Jeff Liebermann wrote:

>>My son has just provided me with a new computer, on which he has put
>>Windoze 7. As there is no longer any O.E. included in the OS, he has put
>>this T-Bird program on as the mail client, and has also configured it to
>>serve as the news client for the text groups that I subscribe to.
>
> (...)
>
> Thunderbird sorta works for Usenet News, but I would recommend Forte
> Agent instead. $29 to register. 30 day free trial.
> <http://www.forteinc.com/agent/index.php>

T-bird works fine for TEXT Usenet newsgroups.

== 2 of 4 ==
Date: Tues, Jun 1 2010 11:09 am
From: Adrian C

On 01/06/2010 18:37, UCLAN wrote:
> Jeff Liebermann wrote:
>
>>> My son has just provided me with a new computer, on which he has put
>>> Windoze 7. As there is no longer any O.E. included in the OS, he has
>>> put this T-Bird program on as the mail client, and has also
>>> configured it to serve as the news client for the text groups that I
>>> subscribe to.
>>
>> (...)
>>
>> Thunderbird sorta works for Usenet News, but I would recommend Forte
>> Agent instead. $29 to register. 30 day free trial.
>> <http://www.forteinc.com/agent/index.php>
>
> T-bird works fine for TEXT Usenet newsgroups.

It's not a perfect job though. Try doing anything slightly advanced with
features you've been given and the brick wall approaches.

For instance, it would be damm useful if the filtering criteria
supported 'regular expression syntax. Er, nope.

Or, if visiting a topic that has been cross-posted in many of ya other
subscribed groups, then having visited posts marked as read in the other
groups would be nice. Er, nope.

Or, where is ROT13 support? (and don't say LeetKey...)

--
Adrian C

== 3 of 4 ==
Date: Tues, Jun 1 2010 3:57 pm
From: "gonzo"

Arfa Daily wrote:
> My son has just provided me with a new computer, on which he has put
> Windoze 7. As there is no longer any O.E. included in the OS, he has
> put this T-Bird program on as the mail client, and has also
> configured it to serve as the news client for the text groups that I
> subscribe to. I always liked O.E. for these, as I found that the way
> it layed out the threads, was simple and intuitive. I also like the
> way that it was simple to put a 'watch' on a thread, and as a result,
> colour the header, and then see it go bold, when there was a new post
> to a thread.
> Thus far, on T-Bird, as far as I can see, it seems to display
> sub-threads within threads, rather than just stacking replies to a
> post below that post. Is there somewhere that I can configure it to
> handle the threading like O.E. did ? Also, how do I put a 'watch' on
> a thread, and can I colour the headers as a result of putting a watch
> on ? What do the little stars to the left of posts mean ? What have I
> switched on when I highlight one ?
>
> Before everyone starts howling that I should use a 'real' mail
> client, I do also use X News, but I never much cared for the way that
> handled text groups, which is why I used O.E. for them.
>
> I know it's probably a bit of 'not liking change',(I'm getting old and
> grumpy !) but I really did like O.E., so would it be better (for me at
> least) to try the new Windoze Mail, which I understand is basically
> O.E. for Vista and above, or possibly, full blown Outlook, which I
> have been told runs fine on W7 ?
>
> Gettin' more confused by the minute ...
>
> Arfa

Apparently Windows Mail is hidden in Win 7 somewhere,
and just needs a tweak to make it work. You mention only
OE, but Windows Mail is nearly identical. Plenty of info
out there.
http://help.lockergnome.com/general/Activate-Windows-Mail-win--ftopict64316.html

== 4 of 4 ==
Date: Tues, Jun 1 2010 8:08 pm
From: David Nebenzahl

On 6/1/2010 10:35 AM UCLAN spake thus:

> Adrian C wrote:
>
>>> this T-Bird program on as the mail client, and has also configured it to
>>> serve as the news client for the text groups that I subscribe to.
>>
>> Don't use it for email. Find another program for that otherwise you'll
>> end up accidently posting private funnies about your budgies love life
>> to the group ;-)
>
> Only if you are brain dead.

Yeah, really. I use T-bird for both mail and Usenet. You just set up
different accounts. Piece of cake.

--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)

==============================================================================
TOPIC: OT: archiving on CD/DVD
http://groups.google.com/group/sci.electronics.repair/t/7865cc1a1f8d8699?hl=en
==============================================================================

== 1 of 1 ==
Date: Tues, Jun 1 2010 10:40 am
From: Jeffrey D Angus

William R. Walsh wrote:
> So far the best longevity I've seen is from paper

I'm a big fan of paper. I have several QRS rolls of digital
music that are almost 100 years old and they still perform
faultlessly.

Jeff

--
"Egotism is the anesthetic that dulls the pain of stupidity."
Frank Leahy, Head coach, Notre Dame 1941-1954

http://www.stay-connect.com

==============================================================================
TOPIC: Unlabelled and disconnected mains primary wires
http://groups.google.com/group/sci.electronics.repair/t/827164e09c1645bf?hl=en
==============================================================================

== 1 of 4 ==
Date: Tues, Jun 1 2010 10:48 am
From: PlainBill47@yahoo.com

On Tue, 1 Jun 2010 10:37:06 +0100, "N_Cook" <diverse@tcp.co.uk> wrote:

>About year 1999, USA make, for export
>In line , not 2 or more separate primary windings, DC ohms to nearest 0.1
>ohm. I'm assuming same gauge wire throughout
>Labelled by me as A,B,C,D,E crossplot (message souce maybe equispaced font)
>
>--- A B C D E
>A --- 9.2 8.5 12.5 1.5
>B 9.2 --- 0.6 3.6 7.6
>C 8.5 0.6 --- 4.2 7.6
>D 12.5 3.6 4.2 --- 11.1
>E 1.5 7.6 7.6 11.1 ---
>
>
>Would D-E / D-A be 220/240Vac or 230/250V ac?
>what would likely be the 110 or 130V interconnctions option ?
>Other than checking using a variac , any other tips ?
>
>
>
>
>
The first step is to rearrange the chart so it makes sense.
The highest resistance is A-D. so A and D are the ends.
A-E is the lowest resistance, so the top line of the chart should now
read

--- A E C B D
A ---1.5 8.5 9.2 12.5

But a better way to look at is is the increments

A-E = winding a = 1.5
E-C = winding b = 7.0
C-B = winding c = 0.7
B-D = winding d = 3.3

NOW let's relabel, and assume that the maximum input voltage is 250
volts (because it's a convenient multiple of 12.5). So the voltage
across each segment (and the taps for each segment) becomes:

A
a = 30
E
b = 140
C
c = 14
B
d = 66
D
Which doesn't make sense for a dual voltage supply UNLESS you assume
multiple gauge wires were used. Which is not unreasonable, factoring
in a desire to save $.02 per device.

Suggestion: A variac (turned down to a very low voltage) would work,
but just about any transformer with an output voltage of 10 -15 volts
should do it. Feed the low voltage AC into the end wirings and
measure the voltage at each tap. Calculate from there.

PlainBill

== 2 of 4 ==
Date: Tues, Jun 1 2010 11:00 am
From: bok118@zonnet.nl (Gerard Bok)

On Tue, 1 Jun 2010 14:12:36 +0100, "N_Cook" <diverse@tcp.co.uk>
wrote:

>Gerard Bok <bok118@zonnet.nl> wrote in message
>news:4c04ef34.3464695@News.Individual.NET...
>> On Tue, 1 Jun 2010 10:37:06 +0100, "N_Cook" <diverse@tcp.co.uk>
>> wrote:
>>
>> >About year 1999, USA make, for export
>> >In line , not 2 or more separate primary windings, DC ohms to nearest 0.1
>> >ohm. I'm assuming same gauge wire throughout
>> >Labelled by me as A,B,C,D,E crossplot (message souce maybe equispaced
>font)
>> >
>> >--- A B C D E
>> >A --- 9.2 8.5 12.5 1.5
>> >B 9.2 --- 0.6 3.6 7.6
>> >C 8.5 0.6 --- 4.2 7.6
>> >D 12.5 3.6 4.2 --- 11.1
>> >E 1.5 7.6 7.6 11.1 ---
>> >
>> >
>> >Would D-E / D-A be 220/240Vac or 230/250V ac?
>> >what would likely be the 110 or 130V interconnctions option ?
>> >Other than checking using a variac , any other tips ?
>>
>> Assuming the beast also has a secundary, --possably even marked
>> with a voltage-- I would apply that voltage (from another
>> transformer) and measure the voltages on the primary terminals.

>I hadn't actually thought of that but problem is which crosslink/s? for 110
>or 130 V operation.

Crosslinks ?
From your original message I read that all primary connections
connect to one continuous winding.

Transformers designed for minimal copper use contain 2 identical
sets of windings. Those get connected in parallel for use on 115
volt and in series for 230 Volt.

As long as there is DC continuity I wouldn't attempt any cross
wiring ;-)

--
Kind regards,
Gerard Bok

== 3 of 4 ==
Date: Tues, Jun 1 2010 10:57 pm
From: "Phil Allison"

<PlainBill47@yahoo.com>

>
> But a better way to look at is is the increments
>
> A-E = winding a = 1.5
> E-C = winding b = 7.0
> C-B = winding c = 0.7
> B-D = winding d = 3.3

** OK - let's assume two gauges of wire ARE being used and the 3.3 ohm
tapping B-D is 100V for Japan.

Then by ratio of resistance, the 0.7 ohm tapping C-B is 20 volts making C-D
120 volts for the USA etc.

Similarly, E-C is another 100 volt tapping ( using thinner wire) making E-D
220 volts for Europe.

Again, A-E is another 20 volt tapping making the whole winding 240 volts.

.... Phil

== 4 of 4 ==
Date: Wed, Jun 2 2010 12:46 am
From: "N_Cook"

Gerard Bok <bok118@zonnet.nl> wrote in message
news:4c054944.6350870@News.Individual.NET...
> On Tue, 1 Jun 2010 14:12:36 +0100, "N_Cook" <diverse@tcp.co.uk>
> wrote:
>
> >Gerard Bok <bok118@zonnet.nl> wrote in message
> >news:4c04ef34.3464695@News.Individual.NET...
> >> On Tue, 1 Jun 2010 10:37:06 +0100, "N_Cook" <diverse@tcp.co.uk>
> >> wrote:
> >>
> >> >About year 1999, USA make, for export
> >> >In line , not 2 or more separate primary windings, DC ohms to nearest
0.1
> >> >ohm. I'm assuming same gauge wire throughout
> >> >Labelled by me as A,B,C,D,E crossplot (message souce maybe equispaced
> >font)
> >> >
> >> >--- A B C D E
> >> >A --- 9.2 8.5 12.5 1.5
> >> >B 9.2 --- 0.6 3.6 7.6
> >> >C 8.5 0.6 --- 4.2 7.6
> >> >D 12.5 3.6 4.2 --- 11.1
> >> >E 1.5 7.6 7.6 11.1 ---
> >> >
> >> >
> >> >Would D-E / D-A be 220/240Vac or 230/250V ac?
> >> >what would likely be the 110 or 130V interconnctions option ?
> >> >Other than checking using a variac , any other tips ?
> >>
> >> Assuming the beast also has a secundary, --possably even marked
> >> with a voltage-- I would apply that voltage (from another
> >> transformer) and measure the voltages on the primary terminals.
>
> >I hadn't actually thought of that but problem is which crosslink/s? for
110
> >or 130 V operation.
>
> Crosslinks ?
> From your original message I read that all primary connections
> connect to one continuous winding.
>
> Transformers designed for minimal copper use contain 2 identical
> sets of windings. Those get connected in parallel for use on 115
> volt and in series for 230 Volt.
>
> As long as there is DC continuity I wouldn't attempt any cross
> wiring ;-)
>
> --
> Kind regards,
> Gerard Bok

This is what was confusing me , I don't often come across USA transformers ,
they must have plenty of copper to waste and unnecessarily larger
transformers. Only ever seem to see 2 separate primaries in the UK , in the
main, maybe some 10 or 20 V taps in addition.
For this continuous one and generally for this sort of mains transformer.
The"240V" ends cannot be returned to form one 110V connection and a mid
point the other 110V connection for that option, as counter winding sense
for the two "halves" and so no secondary volts.
So part of the winding wasted and the 110V
section of primary perhaps a larger gauge. I suppose measuring inductance
may have helped

==============================================================================
TOPIC: Lead free solder
http://groups.google.com/group/sci.electronics.repair/t/23523e78c578fbf8?hl=en
==============================================================================

== 1 of 2 ==
Date: Tues, Jun 1 2010 12:40 pm
From: Baron

ian field Inscribed thus:

>
> "Cydrome Leader" <presence@MUNGEpanix.com> wrote in message
> news:hu3ajp$125$4@reader1.panix.com...
>> ian field <gangprobing.alien@ntlworld.com> wrote:
>>>
>>> "AZ Nomad" <aznomad.3@PremoveOBthisOX.COM> wrote in message
>>> news:slrni07r11.jq6.aznomad.3@ip70-176-155-130.ph.ph.cox.net...
>>>> On Mon, 31 May 2010 10:50:32 +0100, Arfa Daily
>>>> <arfa.daily@ntlworld.com> wrote:
>>>>
>>>>>"ian field" <gangprobing.alien@ntlworld.com> wrote in message
>>>>>news:4wyMn.40637$3B3.19030@hurricane...
>>>>>>
>>>>>> "klem kedidelhopper" <captainvideo462009@gmail.com> wrote in
>>>>>> message
>>>>>>
news:ae548bae-555d-4af8-932b-a3d787ea99c0@t14g2000prm.googlegroups.com...
>>>>>> On May 26, 8:24 pm, AZ Nomad <aznoma...@PremoveOBthisOX.COM>
>>>>>> wrote:
>>>>>>> On Wed, 26 May 2010 08:47:05 -0700, Smitty Two
>>>>>>> <prestwh...@earthlink.net>
>>>>>>> wrote:
>>>>>>> >In article
>>>>>>> ><slrnhvqfec.atf.aznoma...@ip70-176-155-130.ph.ph.cox.net>,
>>>>>>> > AZ Nomad <aznoma...@PremoveOBthisOX.COM> wrote:
>>>>>>> >> On Wed, 26 May 2010 05:25:21 -0700 (PDT), sparky
>>>>>>> >> <sparky...@yahoo.com>
>>>>>>> >> wrote:
>>>>>>>
>>>>>>> >> >Lead free solder was invented by the government since they
>>>>>>> >> >knew it
>>>>>>> >> >would create more jobs (taxes) as the lead free solder
>>>>>>> >> >caused trouble
>>>>>>> >> >and things were thrown out instead of being repaired.
>>>>>>>
>>>>>>> >> surface mount, package pin densities, and labor costs have
>>>>>>> >> guaranteed
>>>>>>> >> that almost nothing is repaired beyond the board level making
>>>>>>> >> solder
>>>>>>> >> type
>>>>>>> >> irrelevent. Even board level repairs are unlikely when the
>>>>>>> >> cost of repairing an item is far higher than its replacement
>>>>>>> >> cost.
>>>>>>>
>>>>>>> >> Leadfree solder was created not to cause electronics be
>>>>>>> >> discarded instead of repaired, but *because* electronics were
>>>>>>> >> being discarded
>>>>>>> >> in
>>>>>>> >> great numbers. Even for items that can be repaired, they
>>>>>>> >> frequently
>>>>>>> >> aren't repaired because anything older than about 18 months
>>>>>>> >> is obsolete in the mind of the consumer.
>>>>>>> >Which is why, to stray completely off-topic, we should replace
>>>>>>> >income
>>>>>>> >tax with a national sales tax. Let the 95% of the masses who
>>>>>>> >are compulsive consumers foot the bill.
>>>>>>>
>>>>>>> Sorry. I didn't know I was responsding to a lunatic.
>>>>>>
>>>>>> Sorry too but I think that these "lunatics" make a whole lot of
>>>>>> sense. I am one of the 5 percent who tries not to purchase
>>>>>> anything new today because unfortunately "new" has become
>>>>>> synonomous with "crap". Nobody wants you to repair anything
>>>>>> anymore. Either the parts are so ridiculously expensive or
>>>>>> they're just not available. I stocked up on lead solder a long
>>>>>> time ago so that I'll be able to repair all my older reliable
>>>>>> "hazardous" electronics well into the future, until the
>>>>>> government makes all repair parts unavailable or comes into my
>>>>>> house with a search warrant for lead based solder that is. So for
>>>>>> the time being, fuck them and the horse their "stimulus package"
>>>>>> rode in on. BTW how is the US military handling this reliability
>>>>>> problem? They wouldn't usually care too much about a small item
>>>>>> like lead poisoning...
>>>>>>
>>>>>> ****************
>>>>>>
>>>>>> The fuckwits who introduced the legislation are well aware that
>>>>>> equipment
>>>>>> made with lead free solder isn't safe, so aerospace, automotive,
>>>>>> military
>>>>>> and medical are exempt.
>>>>>>
>>>>
>>>>>Amen to that ...
>>>>
>>>> Is there a big problem with consumers buying cheap aerospace,
>>>> automotive, military or medical electronics and filling the
>>>> landfills with them?
>>>
>>> There are legal directives compelling that waste electronic
>>> equipment be collected at disposal sites and processed for recovery
>>> of metals and any other recyclable materials, so it makes no
>>> difference what specification it
>>> was originally built to.
>>>
>>> I'd be more concerned by the thousands of miles of abandoned (and
>>> some still
>>> in use!) lead water pipes still in the ground, rain run off from
>>> lead roofing sheets and hoorah-henries/rednecks peppering
>>> agricultural land with
>>> lead shot.
>>
>> It's funny as I saw what looked like lead water pipes being installed
>> in italy in the 1980s.
>>
>> That's how clever and advanced they are in europe.
>
> Actually the Romans invented lead plumbing.

Yup ! We've been using it since they left...

--
Best Regards:
Baron.

== 2 of 2 ==
Date: Tues, Jun 1 2010 6:37 pm
From: Cydrome Leader

ian field <gangprobing.alien@ntlworld.com> wrote:
>
> "Cydrome Leader" <presence@MUNGEpanix.com> wrote in message
> news:hu3agh$125$3@reader1.panix.com...
>> AZ Nomad <aznomad.3@premoveobthisox.com> wrote:
>>> On Mon, 31 May 2010 10:50:32 +0100, Arfa Daily <arfa.daily@ntlworld.com>
>>> wrote:
>>>
>>>>"ian field" <gangprobing.alien@ntlworld.com> wrote in message
>>>>news:4wyMn.40637$3B3.19030@hurricane...
>>>>>
>>>>> "klem kedidelhopper" <captainvideo462009@gmail.com> wrote in message
>>>>> news:ae548bae-555d-4af8-932b-a3d787ea99c0@t14g2000prm.googlegroups.com...
>>>>> On May 26, 8:24 pm, AZ Nomad <aznoma...@PremoveOBthisOX.COM> wrote:
>>>>>> On Wed, 26 May 2010 08:47:05 -0700, Smitty Two
>>>>>> <prestwh...@earthlink.net>
>>>>>> wrote:
>>>>>> >In article <slrnhvqfec.atf.aznoma...@ip70-176-155-130.ph.ph.cox.net>,
>>>>>> > AZ Nomad <aznoma...@PremoveOBthisOX.COM> wrote:
>>>>>> >> On Wed, 26 May 2010 05:25:21 -0700 (PDT), sparky
>>>>>> >> <sparky...@yahoo.com>
>>>>>> >> wrote:
>>>>>>
>>>>>> >> >Lead free solder was invented by the government since they knew it
>>>>>> >> >would create more jobs (taxes) as the lead free solder caused
>>>>>> >> >trouble
>>>>>> >> >and things were thrown out instead of being repaired.
>>>>>>
>>>>>> >> surface mount, package pin densities, and labor costs have
>>>>>> >> guaranteed
>>>>>> >> that almost nothing is repaired beyond the board level making
>>>>>> >> solder
>>>>>> >> type
>>>>>> >> irrelevent. Even board level repairs are unlikely when the cost of
>>>>>> >> repairing an item is far higher than its replacement cost.
>>>>>>
>>>>>> >> Leadfree solder was created not to cause electronics be discarded
>>>>>> >> instead of repaired, but *because* electronics were being discarded
>>>>>> >> in
>>>>>> >> great numbers. Even for items that can be repaired, they frequently
>>>>>> >> aren't repaired because anything older than about 18 months is
>>>>>> >> obsolete in the mind of the consumer.
>>>>>> >Which is why, to stray completely off-topic, we should replace income
>>>>>> >tax with a national sales tax. Let the 95% of the masses who are
>>>>>> >compulsive consumers foot the bill.
>>>>>>
>>>>>> Sorry. I didn't know I was responsding to a lunatic.
>>>>>
>>>>> Sorry too but I think that these "lunatics" make a whole lot of sense.
>>>>> I am one of the 5 percent who tries not to purchase anything new today
>>>>> because unfortunately "new" has become synonomous with "crap". Nobody
>>>>> wants you to repair anything anymore. Either the parts are so
>>>>> ridiculously expensive or they're just not available. I stocked up on
>>>>> lead solder a long time ago so that I'll be able to repair all my
>>>>> older reliable "hazardous" electronics well into the future, until the
>>>>> government makes all repair parts unavailable or comes into my house
>>>>> with a search warrant for lead based solder that is. So for the time
>>>>> being, fuck them and the horse their "stimulus package" rode in on.
>>>>> BTW how is the US military handling this reliability problem? They
>>>>> wouldn't usually care too much about a small item like lead
>>>>> poisoning...
>>>>>
>>>>> ****************
>>>>>
>>>>> The fuckwits who introduced the legislation are well aware that
>>>>> equipment
>>>>> made with lead free solder isn't safe, so aerospace, automotive,
>>>>> military
>>>>> and medical are exempt.
>>>>>
>>>
>>>>Amen to that ...
>>>
>>> Is there a big problem with consumers buying cheap aerospace,
>>> automotive, military or medical electronics and filling the landfills
>>> with them?
>>
>> is there really a big problem with lead from electronics pouring out of
>> landfills?
>>
>> I doubt it. the whole rohs thing and europeans are just stupid.
>
> Only insofar as we obey the braindead wankers in Brussels!

Ever been to brussels?

It's one of the most dirty run down cities I've ever seen.

They also can't line up the train platforms with any of the trains either.
It's really sad.

==============================================================================
TOPIC: IC-28A transmit section carnage
http://groups.google.com/group/sci.electronics.repair/t/2d64dac1e201e106?hl=en
==============================================================================

== 1 of 1 ==
Date: Tues, Jun 1 2010 1:37 pm
From: Jamie

Jeff Liebermann wrote:

> On Mon, 31 May 2010 21:41:25 -0400, Jamie
> <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:
>
>
>>Your assumption is most likely correct... I can give you an idea how
>>ever.. If you can remove the cover of the module, and inspect the board,
>>you may find a crack. You'll need a high temp soldering iron to put it
>>back together.. This is common with RF modules or various types.
>>
>>I've done this 3 times already on different rigs and it worked. Most
>>of the time a crack develops, mostly from abuse. Other times, you have
>>a bad module..
>
>
> It doesn't require abuse. See:
> <http://www.11junk.com/jeffl/pics/drivel/slides/power-amp.html>
> That's the guts of the VHF power module from my Kenwood TM-732A radio.
> The circled areas are where I had to solder the trace back together.
> The two failures were seperated by about 2 years and will probably
> continue at the same interval. My guess(tm) is that it was caused by
> either incomplete baking of the hybrid, or a bad solder paste mix when
> the hybrid was silk screened.
>
> The gaps were almost invisible and very difficult to see. They would
> have been far more visible if I could have shined a light from the
> back, but there's a big copper heat spreader in the way. Instead, I
> found them with an ohmmeter. I started with the probes at the end of
> the conductor trace, which showed no continuity. I slowly moved the
> probes closer to each other and eventually closed in on the break.
>
> Soldering was also rather difficult. The ceramic hybrid is a
> wonderful heatsink and literally sucks all the heat out of the
> soldering iron. I had to use a rather large 850C screwdriver solder
> tip and still managed to do a lousy job of soldering.
>
> Also note on the photograph the two big power xsistors. The goo
> covering them is rather soft and flexible silicon rubber. Please
> resist the temptation to push on it, or you'll break the wire bonds
> underneath.
>
> If desperate, you can get replacement PA modules from RF Parts.
>
I use a mini gas torch that has nice tips for soldering, no flames get
in there but the tip gets hot as hell. The heat sink has no chance of
holding back. :)

==============================================================================
TOPIC: 40Gb Western Digital hard drive
http://groups.google.com/group/sci.electronics.repair/t/d11c27dd9c7d80c0?hl=en
==============================================================================

== 1 of 1 ==
Date: Tues, Jun 1 2010 3:17 pm
From: "Michael A. Terrell"

mike wrote:
>
> Michael A. Terrell wrote:
>
> >
> > One of the computers I refurbished for my 'Computers for Veterans'
> > project was a small HP. I had everything ready, and turned it on one
> > last time to run Belarc Advisor to print out the system information. As
> > soon as I turned it on, flames shot out through the fan. I scrapped
> > it. In fact, I scrap more HP computers than any other brand.
>
> You say a small HP, was it the kind that allows only one hard drive
> and one CD inside (no room for anything more )? If so, it sounds like
> a re-badged EVO - seems like a lot of 'modern' mfgs. just change the
> name of their crap these days, rather than fix the problem...

No, HP construction is obvious. Their part numbers are stamped into
everything.

> > I get free, used UPS fairly often, all with bad or missing
> > batteries. One early unit had eight missing gel cells. they guy who
> > gave it to me took them out and didn't make a note of what was there, or
> > how they were wired. His excuse? "I thought all UPS used the same
> > batteries." The guy is a broadcast engineer. He should klnow better.
> > The OEM was out of business, so I have a large, heavy rack mount UPS on
> > the shelf waiting to be scrapped. I am thinking about turning it into a
> > rack mount server case.
>
> What with the cost and low capacity of the correct replacement gel
> cell battery/-ies for most UPS's, I found it works pretty good on the
> higher capacity ones to make a hole in the side of the UPS and extend
> the battery cables out to some wet cell deep cycle batteries (the 3
> UPS's I've got all use 2 12v ones in series). Since the ones I'm
> using now aren't industrial quality, I make sure the batteries are
> fully charged before initially hooking them up. You need to make sure
> there's good ventilation as a hydrogen gas build up could become a BIG
> problem.

The battery cables would have to be 20' long to put car batteries in
a safe location.

> > I got another rack mount UPS the other day. It is an Alpha Ali Plus
> > 700xl The batteries are missing. The OEM doesn't support it. They may
> > be 12V 7.2AH but I'm not sure. That's too bad, because I picked up a
> > free Dell 4350 server that I would like to put into a rack with the
> > UPS. I want a shop server to hold all the drivers and other programs I
> > use to repair computers, and to learn to administer Apache Server.
>
> What is the difference between a server and a 'normal computer
> anyway? I've got a Compaq Proliant DL 380 rack-mounted server (no
> rack to mount it in though) I've been hoping to figure out how to use
> it like a PC, just out of curiosity as much as anything else.

A server is designed to run 24/7, and should have at least two power
supplies. They generally have three or more hard drives for a small
RAID array. They are better built than a consumer grade computer. You
can use them as a regular computer, but it my not have a high resolution
video card. A consumer type OS may not support multiple processors.

--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.

==============================================================================
TOPIC: DTV decoder repair, capacitor gets too hot
http://groups.google.com/group/sci.electronics.repair/t/2a64f4c6ccba41cd?hl=en
==============================================================================

== 1 of 2 ==
Date: Tues, Jun 1 2010 3:18 pm
From: Jeroni Paul

> What brand and series of  "low ESR high quality 105 deg replacement"
> did you use?  I would recommecd using a Panasonic FM series or
> equivalent ultra-low ESR high quality ca fron Nochicon, UCC, or
> Rubycon for something like this.  
>
> PlainBill

The failed capacitor is "Jun Fu". I have more of these here and they
have the lowest ESR amongst all I measured (KRG, Nichicon, TL). I
found Nichicon in a local shop but it has higher ESR and heats even
more. For Panasonics I will have to shop online. My ESR meter is of
the needle type so I will not post exact measurements but it lets me
compare quite precisely.

Thank you.

== 2 of 2 ==
Date: Tues, Jun 1 2010 3:25 pm
From: Jeroni Paul

On 31 Maig, 03:18, Jamie
<jamie_ka1lpa_not_valid_after_ka1l...@charter.net> wrote:
> Also, you may want to check or replace the UF "ULTRA Fast" diode in that
> circuit. I found some that developed a leak but not enough to short and
> pass some AC through from the switcher.. This can not only heat the
> diode but the Cap. A simple test is to perform a thermal test on the
> diode.. It should only be warm at best..

Good point, the diode gets very hot, too. Will try to replace it.

Thank you to all.

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