Intermittent Faults - Preferred Lay Remedies

Hi,

Can I get peoples opinions on and suggestions of lay / informal remedies to
intermittent faults.

My /one suggestion is "bouncing", such as with a soft surface - e.g. a bed.
"Grasp device at one end, 'bounce' onto and off soft surface. Plug in and
try again".

Thanks.


Best wishes,



News Reader

---

› See More: Intermittent Faults - Preferred Lay Remedies

News Reader wrote:
> Hi,
>
> Can I get peoples opinions on and suggestions of lay / informal
> remedies to intermittent faults.
>
> My /one suggestion is "bouncing", such as with a soft surface - e.g.
> a bed. "Grasp device at one end, 'bounce' onto and off soft surface.
> Plug in and try again".

How very refined.... Much less drastic than the common person's "Give it a
bloody good kicking."

If urgency isn't an issue, I've found that that repeated nagging with escalating
threats sometimes serves.

YMMV

On Tue, 8 May 2007 08:45:40 +0100, Keith Willcocks wrote:

> "cybuerke" <[email protected]> wrote in message
> news:[email protected]...
>> News Reader wrote:
>>> Hi,
>>>
>>> Can I get peoples opinions on and suggestions of lay / informal
>>> remedies to intermittent faults.
>>>
>>> My /one suggestion is "bouncing", such as with a soft surface - e.g.
>>> a bed. "Grasp device at one end, 'bounce' onto and off soft surface.
>>> Plug in and try again".
>>
>> How very refined.... Much less drastic than the common person's "Give it
>> a bloody good kicking."
>>
>> If urgency isn't an issue, I've found that that repeated nagging with
>> escalating threats sometimes serves.
>>
>
> The problem lies in the frustration circuit which is present in all
> electronic equipment. It reduces performance in direct proportion to the
> perceived frustration of the user. You should try sitting back with a cup
> of tea and pretending that you don't really want to go on line anyway.
> ;o)

This circuit also senses the proximity of any qualified person and
immediately suspends the fault until the threat of repair has passed.
--
Peter.
If you can do it today, you didn't put off enough yesterday.

News Reader wrote:
> Hi,
>
> Can I get peoples opinions on and suggestions of lay / informal remedies to
> intermittent faults.
>
> My /one suggestion is "bouncing", such as with a soft surface - e.g. a bed.
> "Grasp device at one end, 'bounce' onto and off soft surface. Plug in and
> try again".
>
> Thanks.
>
>
> Best wishes,
>
>
>
> News Reader
>
>

Hit it with a "virtual" stick, much better than threast.

DH

On Tue, 08 May 2007 08:35:28 GMT, DH <[email protected]> wrote:

>News Reader wrote:
>> Hi,
>>
>> Can I get peoples opinions on and suggestions of lay / informal remedies to
>> intermittent faults.
>>
>> My /one suggestion is "bouncing", such as with a soft surface - e.g. a bed.
>> "Grasp device at one end, 'bounce' onto and off soft surface. Plug in and
>> try again".
>>
>> Thanks.
>>
>>
>> Best wishes,
>>
>>
>>
>> News Reader
>>
>>
>
>Hit it with a "virtual" stick, much better than threast.
>
>DH
Intermiitent faults can often be due to soldered joint or component
problems.
These often depend on temperature. The particular method(s) I have
used have depended on the fault type, these are:-
1. Tap printed circuit boards, in various places, with the non-metalic
part of a screwdriver. This method can be used, gently, on thermionic
devices, such as on the neck of a CRT, if that is suspected.
2. If intermittent noise, try squirting 'freezer' aerosol on
individual components, that you have homed in on, by studying the
circuit/making measurements - i.e. standard fault finding techniques.
3. Use a hairdryer on suspect areas, to raise the temperature, if you
suspect a temperature driven fault.
4.Put it on 'soak' - i.e. give it time, get on with something else but
kep an eye on the performance of the device under test.

If the fault fails to materialise then, at least, clean up the
circuit boards and make sure any switches etc.are cleaned, where
appropriate. Hope this helps!

Remove 'no_spam_' from email address.

In message <[email protected]>, Keith Willcocks
<[email protected]> writes
>
>"cybuerke" <[email protected]> wrote in message
>news:[email protected]...
>> News Reader wrote:
>>> Hi,
>>>
>>> Can I get peoples opinions on and suggestions of lay / informal
>>> remedies to intermittent faults.
>>>
>>> My /one suggestion is "bouncing", such as with a soft surface - e.g.
>>> a bed. "Grasp device at one end, 'bounce' onto and off soft surface.
>>> Plug in and try again".
>>
>> How very refined.... Much less drastic than the common person's "Give it
>> a bloody good kicking."
>>
>> If urgency isn't an issue, I've found that that repeated nagging with
>> escalating threats sometimes serves.
>>
>
>
>The problem lies in the frustration circuit which is present in all
>electronic equipment. It reduces performance in direct proportion to the
>perceived frustration of the user. You should try sitting back with a cup
>of tea and pretending that you don't really want to go on line anyway.

As a former maintenance engineer I was completely convinced that a fault
occupied a point in space. If you replaced faulty equipment then the new
equipment showed the same fault and the old gear was perfectly
serviceable.

Mike
--
M.J.Powell

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

DH wrote:
> News Reader wrote:
>> Hi,
>>
>> Can I get peoples opinions on and suggestions of lay / informal
>> remedies to intermittent faults.
>>
>> My /one suggestion is "bouncing", such as with a soft surface - e.g. a
>> bed. "Grasp device at one end, 'bounce' onto and off soft surface.
>> Plug in and try again".

> Hit it with a "virtual" stick, much better than threast.
>
> DH

May I counter-suggest the Baton of Health and Safety. This
government-approved replacement of the commonplace "stick" is a safe and
environmentally-friendly length of foam with no corners, flammable
materials or sexist/ageist/racist comments inscribed on it (in case of
offence). It is unlikely to damage anything that comes in contact with it,
nor subject the user to any repetitive strain injury, noise damage or risk
of poking one's eye out. It cannot be smoked, so is in compliance with
recent anti-smoking legislation.

It is also RoHS and WEEE WEEE compliant.
- --
Adam Piggott, Proprietor, Proactive Services (Computing).
http://www.proactiveservices.co.uk/

Please replace dot invalid with dot uk to email me.
Apply personally for PGP public key.
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"News Reader" <[email protected]> wrote in message
news:[email protected]...
>
> Hi,
>
> Can I get peoples opinions on and suggestions of lay / informal remedies
> to intermittent faults.
>
> My /one suggestion is "bouncing", such as with a soft surface - e.g. a
> bed. "Grasp device at one end, 'bounce' onto and off soft surface. Plug in
> and try again".
>

In the early '90s we were supplying BBC model B's to Pharmacies.
The PSU suffered from dry-joints and the official trouble-shooting
guide said something like this.

"If the computer fails to start up, lift up the entire machine to a height
of four inches above the bench, and let go"

--
Graham.
%Profound_observation%

On Tue, 8 May 2007 15:56:51 +0100, "Graham" <[email protected]> wrote:

|!
|!"News Reader" <[email protected]> wrote in message
|!news:[email protected]...
|!>
|!> Hi,
|!>
|!> Can I get peoples opinions on and suggestions of lay / informal remedies
|!> to intermittent faults.
|!>
|!> My /one suggestion is "bouncing", such as with a soft surface - e.g. a
|!> bed. "Grasp device at one end, 'bounce' onto and off soft surface. Plug in
|!> and try again".
|!>
|!
|!In the early '90s we were supplying BBC model B's to Pharmacies.
|!The PSU suffered from dry-joints and the official trouble-shooting
|!guide said something like this.
|!
|!"If the computer fails to start up, lift up the entire machine to a height
|!of four inches above the bench, and let go"

I saw this when I was in the RAF. There was a very *large* Senior Tech
Electrical who was a whizz on the Comet aircraft. When he had a snag he
told his little SAC to go and jump by the ??th window on the right/left as
the case may be. The SAC did that and came back. If the snag was still
there the above was repeated. If the snag was still there he heaved
himself out of the Engineers chair trundled down the Comet and jumped by
the ??window on the left/right. The Comet shuddered. The snag
disappeared. It was a sticking relay. He knew where every relay was and
cleared them as above.
--
Dave Fawthrop <sf hyphenologist.co.uk> 165 *Free* SF ebooks.
165 Sci Fi books on CDROM, from Project Gutenberg
http://www.gutenberg.org/wiki/Main_Page Completely Free to any
address in the UK. Contact me on the *above* email address.

DH wrote:
> News Reader wrote:
>> Hi,
>>
>> Can I get peoples opinions on and suggestions of lay / informal
>> remedies to intermittent faults.
>>
>> My /one suggestion is "bouncing", such as with a soft surface - e.g. a
>> bed. "Grasp device at one end, 'bounce' onto and off soft surface.
>> Plug in and try again".
>>
>> Thanks.
>>
>>
>> Best wishes,
>>
>>
>>
>> News Reader
>>
>
> Hit it with a "virtual" stick, much better than threast.
>
> DH


Actually I used to work for Decca in the early 70s at Bridgnorth making colour
TVs. As part of the chassis line test procedure, we were instructed to hit the
metalwork of the chassis with large rubber mallets, specifically to show up
any faults.

A stick ain't far off....

On Tue, 08 May 2007 15:42:15 +0100, Adam Piggott wrote:

> May I counter-suggest the Baton of Health

Should be Heralth half the time.
--
Peter.
If you can do it today, you didn't put off enough yesterday.

On Tue, 8 May 2007 15:56:51 +0100, Graham wrote:

> "News Reader" <[email protected]> wrote in message
> news:[email protected]...
>>
>> Hi,
>>
>> Can I get peoples opinions on and suggestions of lay / informal remedies
>> to intermittent faults.
>>
>> My /one suggestion is "bouncing", such as with a soft surface - e.g. a
>> bed. "Grasp device at one end, 'bounce' onto and off soft surface. Plug in
>> and try again".
>>
>
> In the early '90s we were supplying BBC model B's to Pharmacies.
> The PSU suffered from dry-joints and the official trouble-shooting
> guide said something like this.
>
> "If the computer fails to start up, lift up the entire machine to a height
> of four inches above the bench, and let go"
So you hadn't gone metric?
--
Peter.
If you can do it today, you didn't put off enough yesterday.

On Tue, 8 May 2007 12:49:37 +0100, M. J. Powell wrote:

> In message <[email protected]>, Keith Willcocks
> <[email protected]> writes
>>
>>"cybuerke" <[email protected]> wrote in message
>>news:[email protected]...
>>> News Reader wrote:
>>>> Hi,
>>>>
>>>> Can I get peoples opinions on and suggestions of lay / informal
>>>> remedies to intermittent faults.
>>>>
>>>> My /one suggestion is "bouncing", such as with a soft surface - e.g.
>>>> a bed. "Grasp device at one end, 'bounce' onto and off soft surface.
>>>> Plug in and try again".
>>>
>>> How very refined.... Much less drastic than the common person's "Give it
>>> a bloody good kicking."
>>>
>>> If urgency isn't an issue, I've found that that repeated nagging with
>>> escalating threats sometimes serves.
>>>
>>
>>
>>The problem lies in the frustration circuit which is present in all
>>electronic equipment. It reduces performance in direct proportion to the
>>perceived frustration of the user. You should try sitting back with a cup
>>of tea and pretending that you don't really want to go on line anyway.
>
> As a former maintenance engineer I was completely convinced that a fault
> occupied a point in space. If you replaced faulty equipment then the new
> equipment showed the same fault and the old gear was perfectly
> serviceable.
>
> Mike

It's quite a large space and if also occupied by said me the fault is often
displaced slightly to just outside the equipment.
Could also be time-based.
--
Peter.
If you can do it today, you didn't put off enough yesterday.

"Brian A" <[email protected]> wrote in message
news:[email protected]...
> On Tue, 08 May 2007 08:35:28 GMT, DH <[email protected]> wrote:
>
>>News Reader wrote:
>>> Hi,
>>>
>>> Can I get peoples opinions on and suggestions of lay / informal remedies
>>> to
>>> intermittent faults.
>>>
>>> My /one suggestion is "bouncing", such as with a soft surface - e.g. a
>>> bed.
>>> "Grasp device at one end, 'bounce' onto and off soft surface. Plug in
>>> and
>>> try again".
>>>
>>> Thanks.
>>>
>>>
>>> Best wishes,
>>>
>>>
>>>
>>> News Reader
>>>
>>>
>>
>>Hit it with a "virtual" stick, much better than threast.
>>
>>DH
> Intermiitent faults can often be due to soldered joint or component
> problems.
> These often depend on temperature. The particular method(s) I have
> used have depended on the fault type, these are:-
> 1. Tap printed circuit boards, in various places, with the non-metalic
> part of a screwdriver. This method can be used, gently, on thermionic
> devices, such as on the neck of a CRT, if that is suspected.
> 2. If intermittent noise, try squirting 'freezer' aerosol on
> individual components, that you have homed in on, by studying the
> circuit/making measurements - i.e. standard fault finding techniques.
> 3. Use a hairdryer on suspect areas, to raise the temperature, if you
> suspect a temperature driven fault.
> 4.Put it on 'soak' - i.e. give it time, get on with something else but
> kep an eye on the performance of the device under test.
>
> If the fault fails to materialise then, at least, clean up the
> circuit boards and make sure any switches etc.are cleaned, where
> appropriate. Hope this helps!
>

All those are good.
I worked in a mainframe design lab in the 1960s using TTL and wrapped
backplane joints. Other techniques we used were:
- look for dry joints - any not shiny and with a dusty appearance - and
resolder them.
- wiggle all the wrapped wiring with a stiff brush,
- alter the supply voltage (but within limits). TTL had a tolerance of
4.75 to 5.25 volts but I liked to weed out anything which failed if I took
it down to 4.3 volts.
- flex or twist the printed circuit boards slightly - a real killer for
intermittents but take care of high voltages and static sensitive stuff.
- rattle all the boards. After visiting and fixing one troublesome
system my boss asked me whether I'd rattled the boards. I had, with a
plastic connector cover, but I was reprimanded for not using a hammer. On
a subsequent occasion I was again reprimanded for not physically breaking
any boards with the said hammer!!
Not sure that's particularly good if you want to rely on a warranty though.

Hope that helps.

Phil

> Remove 'no_spam_' from email address.

In message <[email protected]>, Graham <[email protected]>
writes
>
>"News Reader" <[email protected]> wrote in message
>news:[email protected]...
>>
>> Hi,
>>
>> Can I get peoples opinions on and suggestions of lay / informal remedies
>> to intermittent faults.
>>
>> My /one suggestion is "bouncing", such as with a soft surface - e.g. a
>> bed. "Grasp device at one end, 'bounce' onto and off soft surface. Plug in
>> and try again".
>>
>
>In the early '90s we were supplying BBC model B's to Pharmacies.
>The PSU suffered from dry-joints and the official trouble-shooting
>guide said something like this.
>
>"If the computer fails to start up, lift up the entire machine to a height
>of four inches above the bench, and let go"

The GPO Pulse & Bar generator had, in the manual, a sentence which said
"It is quite possible that every component will test within spec but the
equipment fail to work."

And no further advice.

Mike
--
M.J.Powell