sci.electronics.repair - 23 new messages in 8 topics - digest

sci.electronics.repair
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Today's topics:

==============================================================================
TOPIC: Hoist brake solenoid buzzes/fluckers instead of steadily pulling
http://groups.google.com/group/sci.electronics.repair/t/4fc90a76b7174fce?hl=en
==============================================================================

== 1 of 12 ==
Date: Sun, Nov 13 2011 10:39 pm
From: "Bruce L. Bergman (munged human readable)"

On Sun, 13 Nov 2011 11:47:07 -0600, Ignoramus22978
<ignoramus22978@NOSPAM.22978.invalid> wrote:

>On 2011-11-13, BQ340 <bq340@Adelphia.net> wrote:
>> On 11/13/2011 10:21 AM, Ignoramus22978 wrote:
>>
>>>> I am thinking that perhaps this solenoid has two separate coils,
>>>> pulling and holding one, and the holding one is not working or not
>>>> engaging?
>>>>
>>>> Any idea?
>>>>
>>>> thanks
>>
>> There would be more than 2 terminals on it if it had multiple windings.
>>
>> MikeB
>>
>
>OK, I kind of suspected that also (based on my past diesel generator
>experiences).

Yup, it's just a standard box solenoid, probably Dormeyer they make
zillions of them - and all crapped up inside that end-bell. If it was
something fancy it would look it.

Take it apart and clean up all the sliding and metal surfaces, a
little dab of Lubriplate white grease on the moving pole pieces inside
the solenoid, and hit it with some clear-coat to stop the surface rust
on the metal parts - and stop leaving it outside in the rain.

You do NOT want to pull an "Honest Al Babin" and start painting all
over the insides. You want to see if something is starting to crack.

--<< Bruce >>--

== 2 of 12 ==
Date: Mon, Nov 14 2011 12:37 am
From: Gunner Asch

On Sun, 13 Nov 2011 20:52:52 -0600, Ignoramus22978
<ignoramus22978@NOSPAM.22978.invalid> wrote:

>On 2011-11-13, Gunner Asch <gunnerasch@gmail.com> wrote:
>> On Sun, 13 Nov 2011 08:00:33 -0600, Ignoramus22978
>><ignoramus22978@NOSPAM.22978.invalid> wrote:
>>
>>>I have a 3 phase Yale 1/2 ton hoist. It has an electric brake with a
>>>solenoid, whose job is to pull away the brake lever when 230VAC is
>>>supplied to it.
>>>
>>>The problem is that it does not do it. Instead of steadily pulling
>>>away, it constantly jerks the lever, but never far enough to the end
>>>point where it is supposed to be pulled away. So, the brake is not
>>>disengaged as the hoist operates. I am glad that I noticed that.
>>>
>>>I tried pulling on the lever by hand when the solenoid was engaged. I
>>>noticed that if I help the solenoid and pull away the lever to the
>>>end, jerking stops completely, but if I slowly let go of the lever and
>>>it returns to the brake position, jerking resumes.
>>>
>>>I am thinking that perhaps this solenoid has two separate coils,
>>>pulling and holding one, and the holding one is not working or not
>>>engaging?
>>>
>>>Any idea?
>>>
>>>thanks
>>
>> Check to see if its not wired up for 440/480
>>
>> Most of those hoists are dual voltage and while they will run on 220 if
>> wired for 440..the solenoids most often will not
>
>The hoist can be entirely rewired for 240/480. It actually WAS wired
>for 480 and I had to rewire. So, you are saying that to complete this
>transition to 240, I would have to replace the solenoid?
>
>i

No..it means you didnt get everything changed over to 240. Check your
diagrams again. Something is still trying to run at 480 and its not
working..hence the solenoid chattering

Gunner

One could not be a successful Leftwinger without realizing that,
in contrast to the popular conception supported by newspapers
and mothers of Leftwingers, a goodly number of Leftwingers are
not only narrow-minded and dull, but also just stupid.
Gunner Asch

== 3 of 12 ==
Date: Mon, Nov 14 2011 12:39 am
From: Ignoramus22978

On 2011-11-14, Jeffrey Angus <grendelair@aim.com> wrote:
> On 11/13/2011 8:52 PM, Ignoramus22978 wrote:
>> The hoist can be entirely rewired for 240/480. It actually WAS wired
>> for 480 and I had to rewire. So, you are saying that to complete this
>> transition to 240, I would have to replace the solenoid?
>>
>> i
>
> Ok, let's back up a bit. WHEN was the last time the hoist worked
> like it should? When it was installed and operating on 480 v?
>
> Or was it working at some point when re-wired for 240 v and THEN
> started to act up with the brake solenoid?

I bought it at auction.

I have never seen this hoist run.

At my place, I have 240v 3ph only. (well, I have a transformer that I
could wire to get 460v, but it is sitting in the corner right now).

== 4 of 12 ==
Date: Mon, Nov 14 2011 12:40 am
From: Ignoramus22978

On 2011-11-14, Gunner Asch <gunnerasch@gmail.com> wrote:
> On Sun, 13 Nov 2011 20:52:52 -0600, Ignoramus22978
><ignoramus22978@NOSPAM.22978.invalid> wrote:
>
>>On 2011-11-13, Gunner Asch <gunnerasch@gmail.com> wrote:
>>> On Sun, 13 Nov 2011 08:00:33 -0600, Ignoramus22978
>>><ignoramus22978@NOSPAM.22978.invalid> wrote:
>>>
>>>>I have a 3 phase Yale 1/2 ton hoist. It has an electric brake with a
>>>>solenoid, whose job is to pull away the brake lever when 230VAC is
>>>>supplied to it.
>>>>
>>>>The problem is that it does not do it. Instead of steadily pulling
>>>>away, it constantly jerks the lever, but never far enough to the end
>>>>point where it is supposed to be pulled away. So, the brake is not
>>>>disengaged as the hoist operates. I am glad that I noticed that.
>>>>
>>>>I tried pulling on the lever by hand when the solenoid was engaged. I
>>>>noticed that if I help the solenoid and pull away the lever to the
>>>>end, jerking stops completely, but if I slowly let go of the lever and
>>>>it returns to the brake position, jerking resumes.
>>>>
>>>>I am thinking that perhaps this solenoid has two separate coils,
>>>>pulling and holding one, and the holding one is not working or not
>>>>engaging?
>>>>
>>>>Any idea?
>>>>
>>>>thanks
>>>
>>> Check to see if its not wired up for 440/480
>>>
>>> Most of those hoists are dual voltage and while they will run on 220 if
>>> wired for 440..the solenoids most often will not
>>
>>The hoist can be entirely rewired for 240/480. It actually WAS wired
>>for 480 and I had to rewire. So, you are saying that to complete this
>>transition to 240, I would have to replace the solenoid?
>>
>>i
>
> No..it means you didnt get everything changed over to 240. Check your
> diagrams again. Something is still trying to run at 480 and its not
> working..hence the solenoid chattering

Well, what I know is that I did measure voltage at the solenoid
terminals, and it was 230v.

== 5 of 12 ==
Date: Mon, Nov 14 2011 1:24 am
From: Gunner Asch

On Mon, 14 Nov 2011 02:40:30 -0600, Ignoramus22978
<ignoramus22978@NOSPAM.22978.invalid> wrote:

>On 2011-11-14, Gunner Asch <gunnerasch@gmail.com> wrote:
>> On Sun, 13 Nov 2011 20:52:52 -0600, Ignoramus22978
>><ignoramus22978@NOSPAM.22978.invalid> wrote:
>>
>>>On 2011-11-13, Gunner Asch <gunnerasch@gmail.com> wrote:
>>>> On Sun, 13 Nov 2011 08:00:33 -0600, Ignoramus22978
>>>><ignoramus22978@NOSPAM.22978.invalid> wrote:
>>>>
>>>>>I have a 3 phase Yale 1/2 ton hoist. It has an electric brake with a
>>>>>solenoid, whose job is to pull away the brake lever when 230VAC is
>>>>>supplied to it.
>>>>>
>>>>>The problem is that it does not do it. Instead of steadily pulling
>>>>>away, it constantly jerks the lever, but never far enough to the end
>>>>>point where it is supposed to be pulled away. So, the brake is not
>>>>>disengaged as the hoist operates. I am glad that I noticed that.
>>>>>
>>>>>I tried pulling on the lever by hand when the solenoid was engaged. I
>>>>>noticed that if I help the solenoid and pull away the lever to the
>>>>>end, jerking stops completely, but if I slowly let go of the lever and
>>>>>it returns to the brake position, jerking resumes.
>>>>>
>>>>>I am thinking that perhaps this solenoid has two separate coils,
>>>>>pulling and holding one, and the holding one is not working or not
>>>>>engaging?
>>>>>
>>>>>Any idea?
>>>>>
>>>>>thanks
>>>>
>>>> Check to see if its not wired up for 440/480
>>>>
>>>> Most of those hoists are dual voltage and while they will run on 220 if
>>>> wired for 440..the solenoids most often will not
>>>
>>>The hoist can be entirely rewired for 240/480. It actually WAS wired
>>>for 480 and I had to rewire. So, you are saying that to complete this
>>>transition to 240, I would have to replace the solenoid?
>>>
>>>i
>>
>> No..it means you didnt get everything changed over to 240. Check your
>> diagrams again. Something is still trying to run at 480 and its not
>> working..hence the solenoid chattering
>
>Well, what I know is that I did measure voltage at the solenoid
>terminals, and it was 230v.
>
>i

Recheck all your wiring. And then see if the solenoids have any markings
on them that may indicate they were replaced with 480 only ones.

That chattering would indicate they are not getting enough poop to hold.

Got a 480 transformer? Rewire back to 480 and see if it works properly
at that voltage.

If there is 230 on those terminals..it means something is not properly
if the solenoids are the stock ones. So they may not be the stock ones.

Gunner

== 6 of 12 ==
Date: Mon, Nov 14 2011 1:26 am
From: Gunner Asch

On Mon, 14 Nov 2011 02:39:50 -0600, Ignoramus22978
<ignoramus22978@NOSPAM.22978.invalid> wrote:

>On 2011-11-14, Jeffrey Angus <grendelair@aim.com> wrote:
>> On 11/13/2011 8:52 PM, Ignoramus22978 wrote:
>>> The hoist can be entirely rewired for 240/480. It actually WAS wired
>>> for 480 and I had to rewire. So, you are saying that to complete this
>>> transition to 240, I would have to replace the solenoid?
>>>
>>> i
>>
>> Ok, let's back up a bit. WHEN was the last time the hoist worked
>> like it should? When it was installed and operating on 480 v?
>>
>> Or was it working at some point when re-wired for 240 v and THEN
>> started to act up with the brake solenoid?
>
>I bought it at auction.
>
>I have never seen this hoist run.
>
>At my place, I have 240v 3ph only. (well, I have a transformer that I
>could wire to get 460v, but it is sitting in the corner right now).
>
>i
Time to hook it up and set it up as a 480 power supply WITH DIFFERNT
PLUGS than your 240 system. You will run a lot of 480 stuff through
your shop..and you will need a power source to run/demo/test that
stuff.

Gunner

== 7 of 12 ==
Date: Mon, Nov 14 2011 7:20 am
From: Tony Miklos

On 11/13/2011 9:51 PM, Ignoramus22978 wrote:
> On 2011-11-13, Tony Miklos<Tony.Miklos@gmail.com> wrote:
>> On 11/13/2011 12:48 PM, Ignoramus22978 wrote:
>>> On 2011-11-13, Tony Miklos<Tony.Miklos@gmail.com> wrote:
>>>> On 11/13/2011 10:21 AM, Ignoramus22978 wrote:
>>>>> Here's a picture.
>>>>>
>>>>> http://boss-proxy.chudov.com/tmp/tmp-0432.jpg.html
>>>>
>>>> I don't see the wires. How many wires does the solenoid have?
>>>
>>> Two.
>>
>> I've also worked on solenoids like that that have a switch and a
>> resistor for the "hold" circuit. Follow the wires. Same thing, if the
>> resistor or that circuit is open the solenoid will chatter open and closed.
>>
>> This is assuming the solenoid does chatter, as if it's being turned on
>> and off rapidly, like a machine gun.
>
> This is exactly what it does.
>
>> If it's just hanging up part way and buzzing then I'd agree with the
>> people who said to clean it up or replace it.
>
> No, it chatters like a machine gun.
>
> i

Follow the solenoid wires to look for an end of stroke switch. If it
has one it will be actuated and open when the solenoid is pulled in.
Check that circuit for a resistor or something else to lower the
solenoid voltage. The problem is that it gets power on the pull stroke
but no power for the hold position.

== 8 of 12 ==
Date: Mon, Nov 14 2011 7:59 am
From: Jeffrey Angus

On 11/13/2011 9:21 AM, Ignoramus22978 wrote:
> Here's a picture.
>
> http://boss-proxy.chudov.com/tmp/tmp-0432.jpg.html

That amount of surface rust and corrosion INSIDE a cover
indicates it's been wet, or in a wet location.

That's a disc brake and should dis-engage when the hoist
is in operation.

Do you have the wiring diagram for this hoist?

I know that label reads, "Caution dual voltage" as an
indication it "might be wired for a different voltage than
what you're using.

Despite all the random guessing, I'm assuming that is a
very simple straight forward coil that pulls the release
on the disc brake.

If that coil is set up for 480 volts and you're putting 240
across it, it IS going to buzz and chatter. It will do that
without any missing diodes, open coils, hidden switches or
two sets pull & hold windings.

If that coil is set up for "dual voltage" it should have
more that two wires connecting to it. Or there should be a
control transformer somewhere else in the housing to supply
the correct voltage to a single voltage coil. Or a dropping
resistor (not likely) to allow a 240 coil to be used on 480.
And the instructions, as such, should have the connection
for both voltages and everything you have to reconnect listed.

Jeff

--
"Everything from Crackers to Coffins"

== 9 of 12 ==
Date: Mon, Nov 14 2011 1:22 pm
From: Gunner Asch

On Mon, 14 Nov 2011 09:59:40 -0600, Jeffrey Angus <grendelair@aim.com>
wrote:

>On 11/13/2011 9:21 AM, Ignoramus22978 wrote:
>> Here's a picture.
>>
>> http://boss-proxy.chudov.com/tmp/tmp-0432.jpg.html
>
>That amount of surface rust and corrosion INSIDE a cover
>indicates it's been wet, or in a wet location.
>
>That's a disc brake and should dis-engage when the hoist
>is in operation.
>
>Do you have the wiring diagram for this hoist?
>
>I know that label reads, "Caution dual voltage" as an
>indication it "might be wired for a different voltage than
>what you're using.
>
>Despite all the random guessing, I'm assuming that is a
>very simple straight forward coil that pulls the release
>on the disc brake.
>
>If that coil is set up for 480 volts and you're putting 240
>across it, it IS going to buzz and chatter. It will do that
>without any missing diodes, open coils, hidden switches or
>two sets pull & hold windings.
>
>If that coil is set up for "dual voltage" it should have
>more that two wires connecting to it. Or there should be a
>control transformer somewhere else in the housing to supply
>the correct voltage to a single voltage coil. Or a dropping
>resistor (not likely) to allow a 240 coil to be used on 480.
>And the instructions, as such, should have the connection
>for both voltages and everything you have to reconnect listed.
>
>Jeff

The several I own (CMS) have internal transformers that allow voltage
changes. to the workings.

Though he does say that he has 240 on the coils..which is troublesome

Gunner

== 10 of 12 ==
Date: Mon, Nov 14 2011 5:30 pm
From: Jamie

Ignoramus22978 wrote:

> On 2011-11-13, Gunner Asch <gunnerasch@gmail.com> wrote:
>
>>On Sun, 13 Nov 2011 08:00:33 -0600, Ignoramus22978
>><ignoramus22978@NOSPAM.22978.invalid> wrote:
>>
>>
>>>I have a 3 phase Yale 1/2 ton hoist. It has an electric brake with a
>>>solenoid, whose job is to pull away the brake lever when 230VAC is
>>>supplied to it.
>>>
>>>The problem is that it does not do it. Instead of steadily pulling
>>>away, it constantly jerks the lever, but never far enough to the end
>>>point where it is supposed to be pulled away. So, the brake is not
>>>disengaged as the hoist operates. I am glad that I noticed that.
>>>
>>>I tried pulling on the lever by hand when the solenoid was engaged. I
>>>noticed that if I help the solenoid and pull away the lever to the
>>>end, jerking stops completely, but if I slowly let go of the lever and
>>>it returns to the brake position, jerking resumes.
>>>
>>>I am thinking that perhaps this solenoid has two separate coils,
>>>pulling and holding one, and the holding one is not working or not
>>>engaging?
>>>
>>>Any idea?
>>>
>>>thanks
>>
>>Check to see if its not wired up for 440/480
>>
>>Most of those hoists are dual voltage and while they will run on 220 if
>>wired for 440..the solenoids most often will not
>
>
> The hoist can be entirely rewired for 240/480. It actually WAS wired
> for 480 and I had to rewire. So, you are saying that to complete this
> transition to 240, I would have to replace the solenoid?
>
>
If that being the case, I then would assume that maybe the solenoid was
getting its voltage from one of the star windings on the motor?

A connection from wire 4 to wire 5 should provide ~ 230V Ac when the
motor is wired for 480 which is a standard way of doing it, how ever, I
wonder if you considered this when you did your change over?

Of course, I don't know anything about anything so don't listen to me.

Jamie

== 11 of 12 ==
Date: Mon, Nov 14 2011 5:35 pm
From: Jamie

Ignoramus22978 wrote:

> On 2011-11-14, Jeffrey Angus <grendelair@aim.com> wrote:
>
>>On 11/13/2011 8:52 PM, Ignoramus22978 wrote:
>>
>>>The hoist can be entirely rewired for 240/480. It actually WAS wired
>>>for 480 and I had to rewire. So, you are saying that to complete this
>>>transition to 240, I would have to replace the solenoid?
>>>
>>>i
>>
>>Ok, let's back up a bit. WHEN was the last time the hoist worked
>>like it should? When it was installed and operating on 480 v?
>>
>>Or was it working at some point when re-wired for 240 v and THEN
>>started to act up with the brake solenoid?
>
>
> I bought it at auction.
>
> I have never seen this hoist run.
>
> At my place, I have 240v 3ph only. (well, I have a transformer that I
> could wire to get 460v, but it is sitting in the corner right now).
>
> i
Ok, so what is the original coil voltage suppose to be? 230 or 480?

You do know that many of those types of devices that allow you to
rewire uses the same coil for both voltages? Normally the coil is
spec'd out for 230V AC.. which will work in either case, it's just
where you connect the wires to.

Jamie

== 12 of 12 ==
Date: Mon, Nov 14 2011 7:55 pm
From: "hrhofmann@att.net"

On Nov 14, 7:35 pm, Jamie
<jamie_ka1lpa_not_valid_after_ka1l...@charter.net> wrote:
> Ignoramus22978 wrote:
> > On 2011-11-14, Jeffrey Angus <grendel...@aim.com> wrote:
>
> >>On 11/13/2011 8:52 PM, Ignoramus22978 wrote:
>
> >>>The hoist can be entirely rewired for 240/480. It actually WAS wired
> >>>for 480 and I had to rewire. So, you are saying that to complete this
> >>>transition to 240, I would have to replace the solenoid?
>
> >>>i
>
> >>Ok, let's back up a bit. WHEN was the last time the hoist worked
> >>like it should? When it was installed and operating on 480 v?
>
> >>Or was it working at some point when re-wired for 240 v and THEN
> >>started to act up with the brake solenoid?
>
> > I bought it at auction.
>
> > I have never seen this hoist run.
>
> > At my place, I have 240v 3ph only. (well, I have a transformer that I
> > could wire to get 460v, but it is sitting in the corner right now).
>
> > i
>
> Ok, so what is the original coil voltage suppose to be? 230 or 480?
>
> You do know that many of those types of devices that allow you to
> rewire uses the same coil for both voltages? Normally the coil is
> spec'd out for 230V AC.. which will work in either case, it's just
> where you connect the wires to.
>
> Jamie- Hide quoted text -
>
> - Show quoted text -

Has the OP ever said if there are two or three or how many wires going
to the solenoid????

==============================================================================
TOPIC: practical lubricity
http://groups.google.com/group/sci.electronics.repair/t/5cc5af4e785fa664?hl=en
==============================================================================

== 1 of 3 ==
Date: Mon, Nov 14 2011 12:56 am
From: "N_Cook"

William Sommerwerck <grizzledgeezer@comcast.net> wrote in message
news:j9orah$i20$1@dont-email.me...
> The car holder for my GPS navigation system uses a ball-and-socket joint.
It
> holds the unit without any slipping -- but no matter how much I fuss with
> it, I can never get it into exactly the position I want. There's simply
too
> much friction, both static and moving.
>
> I've tried silicone spray lube, but it doesn't do much good. I've thought
of
> lithium grease, but... Nah.
>
> Any suggestions?
>
> Thanks in advance.
>
> --
> "We already know the answers -- we just haven't asked the right
> questions." -- Edwin Land
>
>

I would try locksmith's dry lubricant - ground graphite or talcum powder ,
at least no solvents going to attack the plastic

== 2 of 3 ==
Date: Mon, Nov 14 2011 9:23 am
From: Phil Hobbs

On 11/14/2011 03:56 AM, N_Cook wrote:
> William Sommerwerck<grizzledgeezer@comcast.net> wrote in message
> news:j9orah$i20$1@dont-email.me...
>> The car holder for my GPS navigation system uses a ball-and-socket joint.
> It
>> holds the unit without any slipping -- but no matter how much I fuss with
>> it, I can never get it into exactly the position I want. There's simply
> too
>> much friction, both static and moving.
>>
>> I've tried silicone spray lube, but it doesn't do much good. I've thought
> of
>> lithium grease, but... Nah.
>>
>> Any suggestions?
>>
>> Thanks in advance.
>>
>> --
>> "We already know the answers -- we just haven't asked the right
>> questions." -- Edwin Land
>>
>>
>
>
> I would try locksmith's dry lubricant - ground graphite or talcum powder ,
> at least no solvents going to attack the plastic
>
>

The old slide rule trick is to loosen with graphite and tighten with
chalk dust.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510
845-480-2058

hobbs at electrooptical dot net
http://electrooptical.net

== 3 of 3 ==
Date: Mon, Nov 14 2011 1:45 pm
From: "William Sommerwerck"

> The old slide rule trick is to loosen with graphite
> and tighten with chalk dust.

I used to carry a mini tube of Vaseline to lube my slide rule.

==============================================================================
TOPIC: Tektronix 2215A worth repair?
http://groups.google.com/group/sci.electronics.repair/t/fc4cb167c05d84fd?hl=en
==============================================================================

== 1 of 1 ==
Date: Mon, Nov 14 2011 4:46 am
From: Archon

On 11/13/2011 8:13 PM, Geoff wrote:

>
> Links below for pics taken with webcam. Mesh is visible.
> I have played around with a magnet, can get trace to wobble
> around as expected but it comes back to the same position once
> magnet removed. This is true for the unshielded part behind
> screen and the conical tube shield. I will try a degausser
> once I find or make one
>
> http://i251.photobucket.com/albums/gg302/triode101/focus_limit
> _ccw1.jpg
>
> http://i251.photobucket.com/albums/gg302/triode101/focus_limit
> _cw1.jpg
>
> http://i251.photobucket.com/albums/gg302/triode101/focus_limit
> _ccw2.jpg
>
> http://i251.photobucket.com/albums/gg302/triode101/2215a.jpg
>
> http://i251.photobucket.com/albums/gg302/triode101/2215b.jpg

If the distortion stays constant with the traces as they move up the
screen its not the CRT

If the distortion is fixed in that area of the CRT then the CRT is
internally damaged.

Magnets and deguassers will not cure this.

IMO its a broken CRT

==============================================================================
TOPIC: Standby voltage
http://groups.google.com/group/sci.electronics.repair/t/e4b30dad17892bfe?hl=en
==============================================================================

== 1 of 3 ==
Date: Mon, Nov 14 2011 7:10 am
From: "Vince Schmitt"

Hi!
I need to know if there is supposed to be 5 Volts on the control board on
Visio TV MDL VW37LHDTV20A
Thank you for any info I can get.
Vince

== 2 of 3 ==
Date: Mon, Nov 14 2011 2:23 pm
From: mike

Vince Schmitt wrote:
> Hi!
> I need to know if there is supposed to be 5 Volts on the control board
> on Visio TV MDL VW37LHDTV20A
> Thank you for any info I can get.
> Vince
Can't tell you anything about that model,
but
any device capable of doing anything while in standby, like turn it on with
a remote, must have power somewhere...control board is a likely place.

== 3 of 3 ==
Date: Mon, Nov 14 2011 10:55 pm
From: Franc Zabkar

On Mon, 14 Nov 2011 14:23:45 -0800, mike <spamme9@gmail.com> put
finger to keyboard and composed:

>Vince Schmitt wrote:
>> Hi!
>> I need to know if there is supposed to be 5 Volts on the control board
>> on Visio TV MDL VW37LHDTV20A
>> Thank you for any info I can get.
>> Vince

>Can't tell you anything about that model, but
>any device capable of doing anything while in standby, like turn it on with
>a remote, must have power somewhere...control board is a likely place.

Good point. I'd look for the remote sensor, usually a 3-pin device.
Standard pinout would be Gnd, Vcc, Output, not necessarily in that
order.

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

==============================================================================
TOPIC: Useful Resource ...
http://groups.google.com/group/sci.electronics.repair/t/4ffeeabe6ce63f45?hl=en
==============================================================================

== 1 of 1 ==
Date: Mon, Nov 14 2011 8:49 am
From: "Arfa Daily"

Site I came across today, whilst searching for a Rotel schematic.

http://audio-circuit.dk/Schematics.htm

Hadn't seen it before. Seems to have quite a lot of useful stuff on it.

Arfa

==============================================================================
TOPIC: PS3: red LED flashes
http://groups.google.com/group/sci.electronics.repair/t/016f259658d5333e?hl=en
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== 1 of 1 ==
Date: Mon, Nov 14 2011 9:10 am
From: "Arfa Daily"

"Ray Carlsen" <rcarlsen@tds.net> wrote in message
news:V9%vq.54$ZX.44@newsreading01.news.tds.net...
>> Google PS3 BGA reball
>
> Thanks, Adrian. The first thought that came to mind when I saw the
> reball video is that I've lived too long. ;-) I might try the "flux and
> reheat" process. My eyes are just not up to any more than that.
>
> Ray

I tried these kitchen table 'reflow' processes for a while (although
actually on my professional workbench and using sophisticated hot air rework
equipment !) and I can pretty much say that I had total success with every
one - for about a week ...

Then they come bouncing back. It's known as "YLOD" or yellow light of death.
It is caused by the solder balls under the two BGA ICs giving way due to
thermal cycling, and in no small part I feel, as a result of the fact that
lead free solder is used, which lacks the ductility of the old leaded
solder.

Out of all the ones I did, I think I only had one that survived, and that
was my son's one too. I tried just about every temperature and duration
combination, as well as various different techniques for applying the heat,
including pre-heating the board, and using liquid flux. I tried all sorts of
thermal paste when re-attaching the heatsinks, including large thick dollops
of standard white paste, as Sony themselves seem to favour in the original
construction, thin scrapings of the same stuff, and thin scrapings of artic
silver, as most people on here will swear is the right way to go. In every
case, when reassembled, the unit would come straight back on, and work a
treat. You could play DVDs in it, or use it as a permanently powered media
server for weeks on end, and it would keep going. But send it back to a
serious gamer to actually play games on, and it would be back inside a few
days.

I think that these games are so processor and graphics-engine intensive,
that the amount of heat generated is just too much for any tenuous 'fix'
obtained by the kitchen table methods which are, make no mistake, definitely
*not* actually re-melting solder balls under those ICs.

Just as a matter of interest, the game "Call of Duty" seems to be the big
one for re-killing them.

By all means give it a go, and if you follow the instructions of any of the
people on the net who are publishing these fixes, you probably will get at
result, initially. But don't get too excited, as there will be a good chance
that you will see it come back to haunt you ...

Arfa

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TOPIC: Mixing 4 audio channels to 3?
http://groups.google.com/group/sci.electronics.repair/t/a9c921002b2ed750?hl=en
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== 1 of 1 ==
Date: Mon, Nov 14 2011 6:53 pm
From: The Ghost In The Machine

On Nov 12, 11:09 pm, DaveC <inva...@invalid.net> wrote:
> > With R12 cranked down to minimum R the output of U3 goes down to about
> > 600µVPP out with 2VPP out of the sound card(s), and up to about 6VPP
> > with R12 at 10k so, if you use a 10k pot for R12, there's your center
> > channel volume control.
> > ---
> > JF
>
> Yeah, R12 needs to be a pot. That does it.
>
> Thanks!

OH BROTHER :/ LETS HOPE SO.
BOOWAHAHAHAHAHA !
GOOD LUCK WIT DAT.

PATECUM
TGITM

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TOPIC: HP Photosmart C8180 All-In-One repaired
http://groups.google.com/group/sci.electronics.repair/t/93d07d1a1ef901b0?hl=en
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== 1 of 1 ==
Date: Mon, Nov 14 2011 10:56 pm
From: Franc Zabkar

On Mon, 14 Nov 2011 02:02:43 GMT, Ray Carlsen <rcarlsen@tds.net> put
finger to keyboard and composed:

>Device: HP Model C8180 Photosmart All-In-One Printer/Scanner/Copier
>
>Fault: When plugged in, it power cycles over and over by itself. No
>functions work including Reset (holding power button at AC in).
>
>Repair: Replace four electrolytic capacitors on the internal power
>supply board: C613 and C660 (330uF at 10V), C614 and C662 (680uF at
>6.3V).

Thanks for sharing.

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

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