sci.electronics.repair - 26 new messages in 10 topics - digest

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Today's topics:

==============================================================================
TOPIC: BWS688 is dead
http://groups.google.com/group/sci.electronics.repair/t/b88c19d1c4c5cfb2?hl=en
==============================================================================

== 1 of 2 ==
Date: Tues, May 18 2010 12:40 pm
From: Meat Plow

On Tue, 18 May 2010 12:23:14 -0700, Merciadri Luca wrote:

> On May 18, 8:28 pm, Meat Plow <mhyw...@yahoo.com> wrote:
>> On Tue, 18 May 2010 10:56:56 -0700, Merciadri Luca wrote:
>> > On May 18, 7:53 pm, Meat Plow <mhyw...@yahoo.com> wrote:
>> >> On Tue, 18 May 2010 10:49:02 -0700, Merciadri Luca wrote:
>> >> > On May 18, 7:44 pm, Meat Plow <mhyw...@yahoo.com> wrote:
>> >> >> Sorry to hear one BWS688 isn't working.
>>
>> >> > Huh? That does not bring some new info to the topic. I'm sorry
>> >> > too, but that does not take us further.
>>
>> >> Oh,you wanted to go further? I just thought you were describing some
>> >> equipment you had and how it did or didn't operate. What further did
>> >> you want to know?
>>
>> > Why it does not work...
>>
>> From your description, the transmitter portion seems to have a problem.
>> Check the devices that do the final amplification.
> You mean ... into the transmitter, right? How do I know which ones do
> this?

I would start with a schematic, decide what parts do what and make some
tests with some gear I own designed to troubleshoot various problems
occurring within the device. I'd look for correct voltages, what stages
of the transmitter are operating nominally and then based on my findings
decided a course of action.

By the way did you mention you have any test equipment or posses any
troubleshooting skills or are you just an end-user?

== 2 of 2 ==
Date: Tues, May 18 2010 1:53 pm
From: Merciadri Luca

On May 18, 9:40 pm, Meat Plow <mhyw...@yahoo.com> wrote:
> On Tue, 18 May 2010 12:23:14 -0700, Merciadri Luca wrote:
> > On May 18, 8:28 pm, Meat Plow <mhyw...@yahoo.com> wrote:
> >> On Tue, 18 May 2010 10:56:56 -0700, Merciadri Luca wrote:
> >> > On May 18, 7:53 pm, Meat Plow <mhyw...@yahoo.com> wrote:
> >> >> On Tue, 18 May 2010 10:49:02 -0700, Merciadri Luca wrote:
> >> >> > On May 18, 7:44 pm, Meat Plow <mhyw...@yahoo.com> wrote:
> >> >> >> Sorry to hear one BWS688 isn't working.
>
> >> >> > Huh? That does not bring some new info to the topic. I'm sorry
> >> >> > too, but that does not take us further.
>
> >> >> Oh,you wanted to go further? I just thought you were describing some
> >> >> equipment you had and how it did or didn't operate. What further did
> >> >> you want to know?
>
> >> > Why it does not work...
>
> >> From your description, the transmitter portion seems to have a problem.
> >> Check the devices that do the final amplification.
> > You mean ... into the transmitter, right? How do I know which ones do
> > this?
>
> I would start with a schematic, decide what parts do what and make some
> tests with some gear I own designed to troubleshoot various problems
> occurring within the device. I'd look for correct voltages, what stages
> of the transmitter are operating nominally and then based on my findings
> decided a course of action.
>
> By the way did you mention you have any test equipment or posses any
> troubleshooting skills or are you just an end-user?

Okay. I'm between the end-user and the elec guru. I'll try it. Thanks!

==============================================================================
TOPIC: OT: card storage
http://groups.google.com/group/sci.electronics.repair/t/1faee31fa35fe26a?hl=en
==============================================================================

== 1 of 7 ==
Date: Tues, May 18 2010 12:47 pm
From: "Michael A. Terrell"

Jeffrey D Angus wrote:
>
> Michael A. Terrell wrote:
> > D Yuniskis wrote:
> >> Ha! I'm not sure I want to rely on that sort of
> >> response... :<
> >
> >
> > That's just a sample of Jeff's 'VERY' warped sense of humor. You'll
> > get used to it. ;-)
>
> Aye, but it works. That's the bottom line.

I know it works. :)

I just thought it was only fair to issue the standard warning: 'This
individual is classed as "Mostly Harmless!"' Do not look him directly
in his good eye, or take his last doughnut and your chances of survival
will be 93%. ;-)

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

== 2 of 7 ==
Date: Tues, May 18 2010 12:52 pm
From: "Michael A. Terrell"

D Yuniskis wrote:
>
> You'd be amazed at how quickly that eats up disk space! I scanned
> a disintegrating book on origami a few years ago seeking to
> preserve color, etc. It was over 100MB compressed. You can't
> store very many books if you preserve that much detail. :<

Have you tried 'Paperport'? Its compression is impressive. Its .max
file format makes small files, and you can drag the individual pages
into chapters or whole documents. The basic version was shipped with a
lot of flatbed scanners a few years ago, and includes a stand alone
reader.

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

== 3 of 7 ==
Date: Tues, May 18 2010 1:01 pm
From: D Yuniskis

Michael A. Terrell wrote:
> D Yuniskis wrote:
>> You'd be amazed at how quickly that eats up disk space! I scanned
>> a disintegrating book on origami a few years ago seeking to
>> preserve color, etc. It was over 100MB compressed. You can't
>> store very many books if you preserve that much detail. :<
>
> Have you tried 'Paperport'? Its compression is impressive. Its .max
> file format makes small files, and you can drag the individual pages
> into chapters or whole documents. The basic version was shipped with a
> lot of flatbed scanners a few years ago, and includes a stand alone
> reader.

I have to use formats that are "open" and/or widely
accepted (which often ends up with them being "open").
I don't live in *just* the "Windows World"

== 4 of 7 ==
Date: Tues, May 18 2010 1:44 pm
From: "Michael A. Terrell"

D Yuniskis wrote:
>
> Michael A. Terrell wrote:
> > D Yuniskis wrote:
> >> You'd be amazed at how quickly that eats up disk space! I scanned
> >> a disintegrating book on origami a few years ago seeking to
> >> preserve color, etc. It was over 100MB compressed. You can't
> >> store very many books if you preserve that much detail. :<
> >
> > Have you tried 'Paperport'? Its compression is impressive. Its .max
> > file format makes small files, and you can drag the individual pages
> > into chapters or whole documents. The basic version was shipped with a
> > lot of flatbed scanners a few years ago, and includes a stand alone
> > reader.
>
> I have to use formats that are "open" and/or widely
> accepted (which often ends up with them being "open").
> I don't live in *just* the "Windows World"

Paperport will print to a PDF driver program if you want. I like it for
storing the raw scans because the file size VS image quality is great. I
don't know if it works with other OS or not.

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

== 5 of 7 ==
Date: Tues, May 18 2010 1:54 pm
From: Rich Grise on Google groups

On May 18, 9:43 am, Jeff Liebermann <je...@cruzio.com> wrote:
> scanner, printer, etc conglomeration. Here's a video clip of it
> scanning both sides of service manual:
> <http://802.11junk.com/jeffl/crud/CanonImageRunner5000.wmv>

Man, that's a looooooong download for 15 seconds of video.

Thanks,
Rich

== 6 of 7 ==
Date: Tues, May 18 2010 11:11 pm
From: Paul Keinanen

On Tue, 18 May 2010 10:33:20 -0700, D Yuniskis
<not.going.to.be@seen.com> wrote:

>Hi Paul,
>
>Paul Keinanen wrote:
>>

>> These days 1 TB of storage costs practically nothing (and an other TB
>> for backup), IMHO the source should be scanned and stored with the
>> best available resolution and bit planes, possibly with some very mild
>> compression.
>
>You'd be amazed at how quickly that eats up disk space! I scanned
>a disintegrating book on origami a few years ago seeking to
>preserve color, etc. It was over 100MB compressed. You can't
>store very many books if you preserve that much detail. :<

The storage cost for those 100 MB would be about one cent with current
1 TB drives.

== 7 of 7 ==
Date: Wed, May 19 2010 5:00 am
From: Albert van der Horst

In article <so84v5pq3ghe4udl10q2nokrhh6g7dgam5@4ax.com>,
Paul Keinanen <keinanen@sci.fi> wrote:
>On Mon, 17 May 2010 14:45:04 -0700, D Yuniskis
><not.going.to.be@seen.com> wrote:
>
>>Hi Paul,
>>
>>Paul Keinanen wrote:
>>> On Mon, 17 May 2010 07:37:06 -0700, D Yuniskis
>>> <not.going.to.be@seen.com> wrote:
>
>
>>> Then there is the question how to store the scanned pages and also how
>>> to distribute the (web) pages in a bandwidth efficient way.
>>>
>>> I previously thought that storing and displaying the scanned pages as
>>> simply bilevel (1 bit/pixel) bitmaps (typically run length encoded as
>>> in faxes) would be sufficient, however, such page pictures look
>>> horrible and the OCR software does not reliably make sense of the
>>> text.
>>
>>That is where the manual aspects come into play. You need to review
>>the results of the scan to decide how best to proceed. I've not found
>>any "magic bullet" -- unless you don't care about size (or quality).
>
>I think it is important to keep the distinction between
>scanning/storage format and on the other hand the publishing format.
>
>These days 1 TB of storage costs practically nothing (and an other TB
>for backup), IMHO the source should be scanned and stored with the
>best available resolution and bit planes, possibly with some very mild
>compression.
>
>You can then make some 1 bit/pixel encoding for publishing and heavy
>compression.
>
>After a few years, you can reprocesses your digital source archives,
>without rescanning the original documents when better software is
>available, in order to produce smaller or higher quality publishing
>formats.

A good advice.

>
>>> 1 bit/pixel is really too little and 8 bits/pixel would be excessive.
>>> How many bits/pixel would be sufficient for pleasant visual rendering
>>> or required by OCR software ?
>>
>>It depends on the sizes of the typefaces used. Note that this
>>can vary within a document.
>>
>>And, whether there are illustrations, etc.
>>
>>Sometimes, you get really grainy images -- as if there was
>>dust on the scanner (though it is NOT the scanner that is
>>the source of the problem).
>>
>>For decent typeface sizes, I will use 1bpp at 400-600dpi.
>>This is readable *and* OCR-able (not to be confused with
>>ocre-able -- which is the ability to turn something into ocre!)
>>Other times, I will use 8bpp and drop down to 300dpi
>>(trying to balance the added image depth against the
>>decreased resolution).
>>
>>I wrote some utilities to create *4* bit TIFFs but very few
>>programs will recognize this encoding (despite adhering to the
>>letter of the spec).
>
>4 bit/pixel might be a usable format for _storage_, since this can
>register the varying illumination, the whiteness of the paper and how
>black the ink is. This might be usable information when postprocessing
>to 1 bit/pixel.
>
>>I generally avoid the OCR stage as it requires *lots* of
>>proofreading. Images often get mishandled. Text often
>>gets misrecognized (remember, these are "computer manuals"
>>so "pigx" and "pigy" might be real "words" despite the OCR
>>packages attempts to "fix" them into "pigs" and "piggy", etc.).
>
>As a compromise, you might publish the scans as bit maps, however, it
>might be a good idea to run your original scans through some OCR
>software and use the result to build an index. While a "pig" might be
>a bit unexpected in a computer manual index, there is much less manual
>proofreading.

It seems that Adobe has software to add OCR to a bitmap document.
That means text is searchable. For an example see the old issues
of Forth Dimensions (http//www.forth.org ) under the heading
Forth Online documentation. So although you're looking at
a scan you can search for e.g. DROP and get it right most of the
time.

(But I'm convinced that there will be a time that you ocr
a 19-th century book, and the result will be better than
the original.)

>
>IMHO the worst problem with scanned documents is that it does not
>usually contain a searchable index, so including even somewhat flaked
>index would be a great service.

See above.
>
>>I figure just creating the (electronic) documents is
>>enough of a "donation" so if folks want to grumble, they
>>can go find better versions (hint: most of this stuff is
>>simply NOT AVAILABLE). :>
>>
>>"If you don't like what I'm serving for dinner, you're welcome
>>to eat elsewhere..."
>
>Scanning fragile (and often disintegrating) paper documents is a way
>of preserve our cultural heritage.
>
>Unfortunately, intellectual property laws (with protection times
>decades after the IP holders death), may in fact cause a loss of the
>human intellectual heritage.
>

This is one of my grave concerns. The program SchoonSchip of
(Nobel price winner) Veltman has a nice manual, that is free.
The original manual (197x, mainly of historic interest) sits behind a
(ca) 30 Euro fee. (I'm involved with this, trying to port SchoonSchip
from 68K assembler to Intel.)
It is not hard to imagine a hardcore Elsevier executive to drop
all papers not downloaded for 5 years.
(This has been a seminal activity for the "standard model"
in physics, but what do they know ...)

Throughout history it has been a fight to have libraries in shape.
We don't need another destructive force, besides wars and
ignorance.

Please note that IP laws give protection. We are in no obligation
to exert these rights to the full. A movement that establishes
the habit of pushing all legacy documentation into the public domain
would get my backing.

Groetjes Albert

--
--
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert@spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst

==============================================================================
TOPIC: technics amp SU-Z200 low volume problem
http://groups.google.com/group/sci.electronics.repair/t/9e0b05e00f883d65?hl=en
==============================================================================

== 1 of 2 ==
Date: Tues, May 18 2010 3:04 pm
From: b

I've just found this technics amp in a skip, I'd say mid 80s vintage.,
along with the rest of the system! :-)

The amp only outputs at very low volume - and then for a short while.
Also if you push it up more than 3, it cuts out and needs a power
cycle. Both channels are affected. I noticed R701, 702 (470R)and D701,
702 (Bzv85c) get very hot and there is evidence of some scorching on
the pcb. Might change those diodes.

It uses an STK 4152 II, pretty typical design of the period.

The headphone o/p works normally.

Any suggestions before I go on a cap change oin the o/p stage? anyone
have a schematic?
cheers
B.

== 2 of 2 ==
Date: Tues, May 18 2010 3:24 pm
From: Franc Zabkar

On Tue, 18 May 2010 15:04:03 -0700 (PDT), b
<reverend_rogers@yahoo.com> put finger to keyboard and composed:

>It uses an STK 4152 II, pretty typical design of the period.

FWIW, there is application circuit in the datasheet:
http://www.datasheetarchive.com/pdf-datasheets/Datasheets-316/586035.pdf
http://www.acust.narod.ru/files/PDF/STK4152.PDF

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

==============================================================================
TOPIC: Rega RB300 turntable...
http://groups.google.com/group/sci.electronics.repair/t/6fe769494aca3a1c?hl=en
==============================================================================

== 1 of 6 ==
Date: Tues, May 18 2010 6:09 pm
From: "Arfa Daily"

"Meat Plow" <mhywatt@yahoo.com> wrote in message
news:pan.2010.05.18.16.07.29@gmail.com...
> On Tue, 18 May 2010 16:50:28 +0100, Arfa Daily wrote:
>
>> <snip>
>>
>>
>>
>>> Just another bit of info for what it is worth. The DC resistance of the
>>> motor windings are grey to red = 4k49
>>> grey to blue = 4k49
>>> red to blue = 8k99
>>> grey to motor case greater than 20Meg as read on my oldish dvm
>>> The 220nf cap should be o/c also
>>>
>>> Now I am curious as to what you find. If it is the motor, it might be
>>> worth your customer getting the motor upgrade kit if it still
>>> available. http://www.rega.co.uk/html/upgrade_kits.htm Cheers
>>> DaveD
>>
>>
>> Thanks for the link Dave. Do you know what the reasoning was behind the
>> 'upgrade' ? Did they have a lot of trouble with motors failing ? I would
>> say that this is the original motor, coming up on 25 years old. I fitted
>> the 3 x 47k combination, and the motor runs normally. It has plenty
>> enough torque to shift the heavy glass platter, and according to my
>> strobe disc, the speed is spot on. Voltage across the motor measured at
>> 98v, which would seem right, given that the 47k combo comes to 15.6k
>> against the original value of 12k. In the circumstances, I'm prepared to
>> call 98v on a 110v nominal motor, a draw.
>>
>> I s'pose it wouldn't be a bad idea to just check the winding resistances
>> before it goes back, but I don't think I'll be expecting to find a
>> problem, as it does run correctly, without anything catching fire.
>>
>> As to why the original resistor failed, anyone's guess. About 1 1/4
>> turns of the spiral element have charred, right in the middle. The
>> resistor looks as though it has been pretty warm over its lifetime, but
>> again, it is nearly 25 years old, so has worked hard. Could just be that
>> it had started to go high and suffered a cumulative cascade failure.
>> Might have been a voltage thing. Some of these resistors, particularly
>> considering its age, are not rated especially well, working
>> voltage-wise. I suppose that over it's lifetime, it's had around 130v
>> RMS across it all the time that the motor was running. Could have been a
>> slight manufacturing defect such as the spiral being 'nicked', that has
>> degraded down the years, to the point where it became a failure. Endless
>> possibilities ...
>>
>
> I hate endless possibilities. :)
>

Fact of life in our business, though ... :-|

Arfa

== 2 of 6 ==
Date: Wed, May 19 2010 4:33 am
From: "Ian Iveson"

Arfa Daily wrote:

> Thanks Adam. It is indeed a Planar 3. I had in fact
> already been on that site, and seen the reference to the
> 150 ohm resistor. I suppose it's possible that there might
> be more than one value having been fitted over the life of
> production, because given 40 odd years of looking at burnt
> and discoloured resistor stripes, I definitely would not
> have said that the middle one was originally green, but
> who knows ? (well, hopefully someone on one of these
> groups does ! ) I was pretty sure that the first two were
> brown and red for 1- 2 - something. I was just concerned
> that if the final band was red, or even orange, I didn't
> want to be putting 120 ohms in there ...

What's the resistor for? Assuming the motor draws tens of mA
when running normally, the resistor would need to be a few k
if its purpose is to drop from 240 to 120V.

If it is to drop from UK mains to 220V, then 120 or 150 ohms
would be the right order of magnitude. If an increase in
value is advisable, then that should reflect a proportional
increase in the difference between 220 and UK mains, so an
increase from 120 to 150 ohms would be reasonable.

It's common for motor drivers to use fuse resistors to save
the motor from burning out if it stalls or jams. It could be
that, in your case, the choice of resistor power rating
suitable for protecting the motor is such that the resistor
runs habitually hot, and fails occasionally. I guess a
higher power rating, in combination with a higher
temperature coefficient, might protect the motor equally
well, whilst not burning out so quick under normal
conditions.

Ian

== 3 of 6 ==
Date: Wed, May 19 2010 5:12 am
From: PeterD

On Wed, 19 May 2010 12:33:27 +0100, "Ian Iveson"
<IanIveson.home@blueyonder.co.uk> wrote:

>Arfa Daily wrote:
>
>> Thanks Adam. It is indeed a Planar 3. I had in fact
>> already been on that site, and seen the reference to the
>> 150 ohm resistor. I suppose it's possible that there might
>> be more than one value having been fitted over the life of
>> production, because given 40 odd years of looking at burnt
>> and discoloured resistor stripes, I definitely would not
>> have said that the middle one was originally green, but
>> who knows ? (well, hopefully someone on one of these
>> groups does ! ) I was pretty sure that the first two were
>> brown and red for 1- 2 - something. I was just concerned
>> that if the final band was red, or even orange, I didn't
>> want to be putting 120 ohms in there ...
>
>What's the resistor for? Assuming the motor draws tens of mA
>when running normally, the resistor would need to be a few k
>if its purpose is to drop from 240 to 120V.
>
>If it is to drop from UK mains to 220V, then 120 or 150 ohms
>would be the right order of magnitude.

Well the turntable draws about 4 watts according the the OP (or
someone else in this thread). So that's 30 MA. To drop 120 volts (240
to 120)at that current and power you would have to use a resistor of
4K. But since half that power is the motor, and half is the resistor,
twice the value (8K) is more appropriate. 120 ohms would result in a
current draw at 120 volts of hundreds of watts!

>If an increase in
>value is advisable, then that should reflect a proportional
>increase in the difference between 220 and UK mains, so an
>increase from 120 to 150 ohms would be reasonable.
>
>It's common for motor drivers to use fuse resistors to save
>the motor from burning out if it stalls or jams. It could be
>that, in your case, the choice of resistor power rating
>suitable for protecting the motor is such that the resistor
>runs habitually hot, and fails occasionally. I guess a
>higher power rating, in combination with a higher
>temperature coefficient, might protect the motor equally
>well, whilst not burning out so quick under normal
>conditions.
>
>Ian
>

== 4 of 6 ==
Date: Wed, May 19 2010 5:14 am
From: "William Sommerwerck"

Many turntables have a line resistor. It "does something" (that I don't
understand) to improve speed stability. Or torque. Or something. It's not to
reduce the line voltage.

== 5 of 6 ==
Date: Wed, May 19 2010 6:05 am
From: Roger Thorpe

William Sommerwerck wrote:
> Many turntables have a line resistor. It "does something" (that I don't
> understand) to improve speed stability. Or torque. Or something. It's not to
> reduce the line voltage.
>
>
It's a while since I looked, and I could be wrong but:
The Rega planar motor is a pair of multi pole two phase synchronous
pancake motors sandwiched together with the poles interleaved.
The resistor and capacitor are there to change the phase (lag or lead?)
of one motor so that the assemlby turns in the right direction when it
is started.
Incidentally mine is a Rega 2 and the resistor burnt out too. A day
after a short friendly 'phone conversation with the company the postman
handed me an envelope containing a new resistor (with a higher power
rating).
--
Roger Thorpe

...Wait a minute, It's stopped raining/
Guys are swimming, guys are sailing.....

== 6 of 6 ==
Date: Wed, May 19 2010 7:11 am
From: Jim Lesurf

In article <ht0nne$fa8$1@corncockle-nntp.csv.warwick.ac.uk>, Roger Thorpe
<myinitial.mysurname@warwick.ac.uk> wrote:
> William Sommerwerck wrote:
> > Many turntables have a line resistor. It "does something" (that I
> > don't understand) to improve speed stability. Or torque. Or something.
> > It's not to reduce the line voltage.
> >
> >
> It's a while since I looked, and I could be wrong but: The Rega planar
> motor is a pair of multi pole two phase synchronous pancake motors
> sandwiched together with the poles interleaved. The resistor and
> capacitor are there to change the phase (lag or lead?) of one motor so
> that the assemlby turns in the right direction when it is started.

That chimes with my understanding, based purely on having had to 'fix' a
similar problem with a friend's Rega a few years ago. Haven't commented
previously as I don't know the full details. I just replaced the burnt out
resistor with one rated at a higher power. And have since forgotten the
value.

Must admit I was less than impressed with the circuit at the time. From
this thread it does look like this resistor is prone to burning. Although
perhaps that is made worse by the risk of the motor being stalled or
loaded.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

==============================================================================
TOPIC: CRT Monitor loses Green
http://groups.google.com/group/sci.electronics.repair/t/6da9bcb5dccd722b?hl=en
==============================================================================

== 1 of 1 ==
Date: Tues, May 18 2010 7:04 pm
From: mike

jamesw@eatitall.com wrote:
> My CRT monitor loses the green from time to time. Then the screen is
> all pink in the background and I can only see red and blue. Just
> about the time I'm going to toss it, the green comes back and it has
> the excellent color it's had for years. I really hate to toss it out.
> I know a fair amount about electronics and have done some tv repair.
> This is a 15" computer monitor so it's basically a tv without a tuner.
> Besides that, it seems that the only way to get a CRT monitor these
> days is a used one on ebay or a garage sale. I really do not want a
> LCD monitor, they're too hard to see if they are at a slight angle,
> and because I edit graphics, the low priced LCD screens are just too
> low in resolution and I can not afford a high end one.
>
> Any idea what might be causing this? The green may be gone for a few
> hours or as much as 2 days. Then suddenly it pops right back. The
> screen is not only ugly right now (no green at the moment), but hard
> to see because it's brightness is reduced without the green. I'll
> probably his some garage sales this weekend, but I'd still like to see
> if i can fix this one. Appreciate any help.
>
> Thanks
>
> James
>
>
>
You should, as others have suggested, look for bad connections in the
signal path. Put a scope on the CRT so you can look for signal when it
goes out.

If it turns out to be the CRT, and you've exhausted all other options,
you might try hitting it with a stun gun.
I've fixed shorted CRT elements that way.
Be careful to get all the electronic stuff VERY FAR AWAY so you don't blow
up good semiconductors in the process.

==============================================================================
TOPIC: Allah, CREATED THE UNIVERSE FROM NOTHING
http://groups.google.com/group/sci.electronics.repair/t/d304b0e66e9026f0?hl=en
==============================================================================

== 1 of 2 ==
Date: Tues, May 18 2010 7:15 pm
From: sparky

On May 14, 1:11 pm, عبدلله <ahmd...@yahoo.com> wrote:
> Allah, CREATED THE UNIVERSE FROM NOTHING

Did allah create Moe to look after all the little girls ?

== 2 of 2 ==
Date: Wed, May 19 2010 5:05 am
From: PeterD

On Tue, 18 May 2010 19:15:32 -0700 (PDT), sparky <sparky12x@yahoo.com>
wrote:

>On May 14, 1:11 pm, ?????? <ahmd...@yahoo.com> wrote:
>> Allah, CREATED THE UNIVERSE FROM NOTHING
>
>
>Did allah create Moe to look after all the little girls ?

And little boys and sheep...

In Allahland men are men and sheep are scared shitless.

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

== 1 of 1 ==
Date: Tues, May 18 2010 8:54 pm
From: David Brodbeck

On May 18, 3:36 am, "Phil Allison" <phi...@tpg.com.au> wrote:
> ** Did you read the warning above about tants I just gave you ???
>
> There is no reason to use them if space permits a normal electro.

OK, fair enough. I wasn't sure if they had different leakage
characteristics or something like that.

==============================================================================
TOPIC: PAY PER CLICK
http://groups.google.com/group/sci.electronics.repair/t/7753735c7d2c8782?hl=en
==============================================================================

== 1 of 2 ==
Date: Tues, May 18 2010 11:34 pm
From: NEELU

PAY PER CLICK
---------------------
http://sites.google.com/site/payperclickaffiliatesearn/
***
http://sites.google.com/site/medicalmalpracticelawmichigan/
***
http://sites.google.com/site/onlineinsurancequotesapply/
***
http://sites.google.com/site/laptopdatarecoverysoftware/
***
http://sites.google.com/site/benchmarklendinggroup/

== 2 of 2 ==
Date: Wed, May 19 2010 5:12 am
From: PeterD

On Tue, 18 May 2010 23:34:15 -0700 (PDT), NEELU
<lsewingenterpris@rediffmail.com> wrote:

>PAY PER DICK
>---------------------
>...

Why would anyone want to click a malware site?

==============================================================================
TOPIC: DVD/CD platter widget
http://groups.google.com/group/sci.electronics.repair/t/6d0ca5a294165a11?hl=en
==============================================================================

== 1 of 1 ==
Date: Wed, May 19 2010 12:12 am
From: "N_Cook"

Ended up with drop of superglue and capilliary and kept the platter spinning
for an hour with a small motor and O ring over plastic drive pulley. Didn't
like the idea of playing CD for that time as not sure what vapours would
come off in an enclosed space

==============================================================================
TOPIC: Fluke Scopemeter 199
http://groups.google.com/group/sci.electronics.repair/t/0cfaff10705fe0ca?hl=en
==============================================================================

== 1 of 2 ==
Date: Wed, May 19 2010 12:33 am
From: Pat Jordan

On May 18, 6:33 pm, Merciadri Luca <merciadril...@gmail.com> wrote:
> On May 18, 4:07 pm, Pat Jordan <mymailgene...@gmail.com> wrote:
>
CHB voltage fluctuates greatly with nothing attached. Suspect Philips
000262HL N1E5Y9 HSH0144 i.c but cannot find a reference to this semi
on the web. Cost of repair is ridiculously high - could buy a
competitors scope for the cost quoted for repair! Any ideas?

>
> The fact is that, as you know, Fluke is some kind of trustmark. It'd
> be better to replace the defective component than to go for a
> competitor main unit. For the rest, I cannot tell you more about how
> to find a solution.

Thanks Merciadi Luca, I have several thousand Euros worth of Fluke
test equipment as I believed they were dependable.

== 2 of 2 ==
Date: Wed, May 19 2010 8:56 am
From: Merciadri Luca

On May 19, 9:33 am, Pat Jordan <mymailgene...@gmail.com> wrote:
> On May 18, 6:33 pm, Merciadri Luca <merciadril...@gmail.com> wrote:> On May 18, 4:07 pm, Pat Jordan <mymailgene...@gmail.com> wrote:
>
> CHB voltage fluctuates greatly with nothing attached. Suspect Philips
> 000262HL N1E5Y9 HSH0144 i.c but cannot find a reference to this semi
> on the web. Cost of repair is ridiculously high - could buy a
> competitors scope for the cost quoted for repair! Any ideas?
>
>
>
> > The fact is that, as you know, Fluke is some kind of trustmark. It'd
> > be better to replace the defective component than to go for a
> > competitor main unit. For the rest, I cannot tell you more about how
> > to find a solution.
>
> Thanks Merciadi Luca, I have several thousand Euros worth of Fluke
> test equipment as I believed they were dependable.
So, why would you look in the concurrence?

==============================================================================

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sci.electronics.repair - 26 new messages in 10 topics - digest

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