sci.electronics.repair
http://groups.google.com/group/sci.electronics.repair?hl=en

sci.electronics.repair@googlegroups.com

Today's topics:

* Yamaha Stagepas 500W - 2 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/ffe9b12e2d51ee46?hl=en
* Favorite Cutters For Snipping DIP Leads? - 7 messages, 5 authors
http://groups.google.com/group/sci.electronics.repair/t/30d89f0c2d193f6d?hl=en
* another odd battery problem - 2 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/845e39030c509722?hl=en
* Why use a contactor? - 10 messages, 7 authors
http://groups.google.com/group/sci.electronics.repair/t/8a277d142156dff2?hl=en
* 1/4" phone jack replacement for Behringer 215 speaker. - 5 messages, 2
authors
http://groups.google.com/group/sci.electronics.repair/t/0fd5e32c8baa1611?hl=en

==============================================================================
TOPIC: Yamaha Stagepas 500W
http://groups.google.com/group/sci.electronics.repair/t/ffe9b12e2d51ee46?hl=en
==============================================================================

== 1 of 2 ==
Date: Sat, Jan 11 2014 5:52 am
From: N_Cook


On 11/01/2014 13:00, dave wrote:
> On 01/10/2014 07:28 AM, N_Cook wrote:
>> Just in case someone out there other than myself dares to take on these,
>> and any ideas. All the previous times as far as the PAs are concerned
>> just matter of replacing SMD fusible resitors and powerFETs. This time
>> done that but unit goes into protect mode. With known good PA only or no
>> PA in there, then no flashing green power LED = protect mode.
>> I bench test these little 2 ounce, 250W, "digital" PAs as far as
>> quiesence is concerned and with +/-30V supply rails , sits there happily
>> with normal , for this minimal test, 0.7mA balanced current draw.
>> Cold testing DVM-D fashion has shown up no difference to the known good
>> PA SMDs.
>> I suspect something in the protect monitoring part of the pa has gone
>> wrong at the original failure but its a workup to make extenders etc to
>> probe these amps in full live circuit. At least the schematics etc are
>> out there for these amps.
>
> Have you checked for oscillation?

As distinct from bench testing without the clock signal input I suppose.
Will do that but as bench current drain is only .7mA looks as though
I'll have to defeat the ERR line from this bad amp and add some droppers
in its power lines. At the moment the little bad PA is unplugged and
powered from the bench ps. This amp , like the other ones of 150W rating
, when on +&-30V settle with the speaker output at about -1.5 to -1.7V
and both sets of gates , and D settle to near enough always the same
readings. Then properly in circuit with +&-48V and clock , but still no
speaker load they settle to 10mV DC or so.
With bad amp in hte unit and powered up and before it cuts out I will
monitor for oscillation. Unfortunately with triggering of this protect
you have to wait 5 minutes for a cap to discharge, I must locate that so
I can manually discharge it.
Changing the preset value on this one makes no difference to the -1.6V.
I may try a bench oscillator fed to the clock of this amp, unusual
exercise if nothing else





== 2 of 2 ==
Date: Sat, Jan 11 2014 8:24 am
From: N_Cook


On 11/01/2014 13:52, N_Cook wrote:
> On 11/01/2014 13:00, dave wrote:
>> On 01/10/2014 07:28 AM, N_Cook wrote:
>>> Just in case someone out there other than myself dares to take on these,
>>> and any ideas. All the previous times as far as the PAs are concerned
>>> just matter of replacing SMD fusible resitors and powerFETs. This time
>>> done that but unit goes into protect mode. With known good PA only or no
>>> PA in there, then no flashing green power LED = protect mode.
>>> I bench test these little 2 ounce, 250W, "digital" PAs as far as
>>> quiesence is concerned and with +/-30V supply rails , sits there happily
>>> with normal , for this minimal test, 0.7mA balanced current draw.
>>> Cold testing DVM-D fashion has shown up no difference to the known good
>>> PA SMDs.
>>> I suspect something in the protect monitoring part of the pa has gone
>>> wrong at the original failure but its a workup to make extenders etc to
>>> probe these amps in full live circuit. At least the schematics etc are
>>> out there for these amps.
>>
>> Have you checked for oscillation?
>
> As distinct from bench testing without the clock signal input I suppose.
> Will do that but as bench current drain is only .7mA looks as though
> I'll have to defeat the ERR line from this bad amp and add some droppers
> in its power lines. At the moment the little bad PA is unplugged and
> powered from the bench ps. This amp , like the other ones of 150W rating
> , when on +&-30V settle with the speaker output at about -1.5 to -1.7V
> and both sets of gates , and D settle to near enough always the same
> readings. Then properly in circuit with +&-48V and clock , but still no
> speaker load they settle to 10mV DC or so.
> With bad amp in hte unit and powered up and before it cuts out I will
> monitor for oscillation. Unfortunately with triggering of this protect
> you have to wait 5 minutes for a cap to discharge, I must locate that so
> I can manually discharge it.
> Changing the preset value on this one makes no difference to the -1.6V.
> I may try a bench oscillator fed to the clock of this amp, unusual
> exercise if nothing else
>

I hate the chicken and egg nature of long-tail pair pre-driver stages.





==============================================================================
TOPIC: Favorite Cutters For Snipping DIP Leads?
http://groups.google.com/group/sci.electronics.repair/t/30d89f0c2d193f6d?hl=en
==============================================================================

== 1 of 7 ==
Date: Sat, Jan 11 2014 7:57 am
From: Doug White


N_Cook <diverse@tcp.co.uk> wrote in news:laqv7h$v0t$1@dont-email.me:

> On 11/01/2014 02:40, Doug White wrote:
>> I have occasional need to cut the leads on a standard DIP to remove
it
>> from a PCB. If the chip is dead or not worth saving, and the circuit
>> board is delicate, I'd rather cut the leads & pull them one at a time
>> rather than risk damaging the board trying to yank it all at once.
>>
>> The catch is that my pointiest cutters are a bit broad, and won't
really
>> fit down between the leads far enough to get a good cut. The ones I
>> have are Utica 582E angle tip cutters, similar to these:
>>
>> http://www.stanleysupplyservices.com/erem-angled-tip-cutters/g/329
>>
>> Given the cost of a really good pair of cutters, and the generally
poor
>> quality of the pictures/descriptions supplied by most tool vendors,
I'd
>> rather not blow big bucks on them sight unseen.
>>
>> Does anyone have a particular make & model they can recommend?
>>
>> Thanks!
>>
>> Doug White
>>
> 0.5mm thick abrasive disc or cintride/"diamond" disc in a "Dremmel"

Thus throwing small conductive bits all over the board. No thanks...

Doug White





== 2 of 7 ==
Date: Sat, Jan 11 2014 8:01 am
From: Doug White


tuinkabouter <dachthetniet@net.invalid> wrote in
news:lard1b$vlb$1@dont-email.me:

> On 1/11/2014 3:40 AM, Doug White wrote:
>> I have occasional need to cut the leads on a standard DIP to remove
>> it from a PCB. If the chip is dead or not worth saving, and the
>> circuit board is delicate, I'd rather cut the leads & pull them one
>> at a time rather than risk damaging the board trying to yank it all
>> at once.
>>
>> The catch is that my pointiest cutters are a bit broad, and won't
>> really fit down between the leads far enough to get a good cut. The
>> ones I have are Utica 582E angle tip cutters, similar to these:
>>
>> http://www.stanleysupplyservices.com/erem-angled-tip-cutters/g/329
>>
>> Given the cost of a really good pair of cutters, and the generally
>> poor quality of the pictures/descriptions supplied by most tool
>> vendors, I'd rather not blow big bucks on them sight unseen.
>>
>> Does anyone have a particular make & model they can recommend?
>
> Bit expensive:
> http://uk.farnell.com/bernstein-werkzeugfabrik/3-675-15/cutter-top-
oblique-conductive/dp/9727086

Actually, if you shop around, they can be had considerably cheaper than
the Erem cutters:

http://www.tme.eu/en/details/brn-3-675-15/cutting-pliers/bernstein/3-
675-15/

If I don't get any better suggestions, I'll try them out.

Thanks!

Doug White




== 3 of 7 ==
Date: Sat, Jan 11 2014 8:06 am
From: Doug White


tuinkabouter <dachthetniet@net.invalid> wrote in
news:lardd4$1mm$1@dont-email.me:

> On 1/11/2014 1:10 PM, tuinkabouter wrote:
>> On 1/11/2014 3:40 AM, Doug White wrote:
>>> I have occasional need to cut the leads on a standard DIP to remove
>>> it from a PCB. If the chip is dead or not worth saving, and the
>>> circuit board is delicate, I'd rather cut the leads & pull them one
>>> at a time rather than risk damaging the board trying to yank it all
>>> at once.
>>>
>>> The catch is that my pointiest cutters are a bit broad, and won't
>>> really fit down between the leads far enough to get a good cut. The
>>> ones I have are Utica 582E angle tip cutters, similar to these:
>>>
>>> http://www.stanleysupplyservices.com/erem-angled-tip-cutters/g/329
>>>
>>> Given the cost of a really good pair of cutters, and the generally
>>> poor quality of the pictures/descriptions supplied by most tool
>>> vendors, I'd rather not blow big bucks on them sight unseen.
>>>
>>> Does anyone have a particular make & model they can recommend?
>>
>> Bit expensive:
>> http://uk.farnell.com/bernstein-werkzeugfabrik/3-675-15/cutter-top-
obl
>> ique-conductive/dp/9727086
>
> See partnumber 3-674-15 too:
> www.farnell.com/datasheets/1655808.pdf

Thanks! Actually, the 3-672-15's look even better. I don't need the
heavily angled tip, it's just what I currently have. In some
situations, it can cause issues with bumping into obstacles. Something
really skinny with less angle would allow me to cut more from straight
above, which is usually the only direction I'm guaranteed to have
access.

Doug White




== 4 of 7 ==
Date: Sat, Jan 11 2014 8:46 am
From: Kaz Kylheku


On 2014-01-11, Doug White <gwhite@alum.mit.edu> wrote:
>> 0.5mm thick abrasive disc or cintride/"diamond" disc in a "Dremmel"
>
> Thus throwing small conductive bits all over the board. No thanks...

Reconsider your objection. You can blow the filings away with compressed air,
and vacuum up.

The board is not powered up while you're doing this, right?

You could also mask the board off with a piece of paper (or whatever) that has
a cutout just for the IC, if you're paranoid.




== 5 of 7 ==
Date: Sat, Jan 11 2014 11:12 am
From: N_Cook


On 11/01/2014 16:46, Kaz Kylheku wrote:
> On 2014-01-11, Doug White <gwhite@alum.mit.edu> wrote:
>>> 0.5mm thick abrasive disc or cintride/"diamond" disc in a "Dremmel"
>>
>> Thus throwing small conductive bits all over the board. No thanks...
>
> Reconsider your objection. You can blow the filings away with compressed air,
> and vacuum up.
>
> The board is not powered up while you're doing this, right?
>
> You could also mask the board off with a piece of paper (or whatever) that has
> a cutout just for the IC, if you're paranoid.
>

Its not as though the bits of metal grow dendrite or tin-whisker
fashion. You'd have to be extremly unlucky to end up with a continous
patch of dozens of minute particles forming a continuous path.
Similar situation with solder paste, you cannot guarantee making all
those tiny balls molten and aggregate together as one




== 6 of 7 ==
Date: Sat, Jan 11 2014 11:16 am
From: "Michael A. Terrell"



Kaz Kylheku wrote:
>
> On 2014-01-11, Doug White <gwhite@alum.mit.edu> wrote:
> >> 0.5mm thick abrasive disc or cintride/"diamond" disc in a "Dremmel"
> >
> > Thus throwing small conductive bits all over the board. No thanks...
>
> Reconsider your objection. You can blow the filings away with compressed air,
> and vacuum up.
>
> The board is not powered up while you're doing this, right?
>
> You could also mask the board off with a piece of paper (or whatever) that has
> a cutout just for the IC, if you're paranoid.


Sure you can, if you like to do things wrong. We leased special air
nozzles at Microdyne to eliminate the static charge caused by the air
stream. This prevented ESD to sensitive components.


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




== 7 of 7 ==
Date: Sat, Jan 11 2014 11:38 am
From: Edward Knobloch


On 1/10/2014 9:40 PM, Doug White wrote:
> I have occasional need to cut the leads on a standard DIP to remove it
> from a PCB. If the chip is dead or not worth saving, and the circuit
> board is delicate, I'd rather cut the leads& pull them one at a time
> rather than risk damaging the board trying to yank it all at once.
<snip>
> Does anyone have a particular make& model they can recommend?

Hi,

I like the Xcelite model 170M

http://www.amazon.com/Xcelite-170M-General-Shearcutter-Diagonal/dp/B0002BBZIS

73,
Ed Knobloch






==============================================================================
TOPIC: another odd battery problem
http://groups.google.com/group/sci.electronics.repair/t/845e39030c509722?hl=en
==============================================================================

== 1 of 2 ==
Date: Sat, Jan 11 2014 12:49 pm
From: "William Sommerwerck"


I attacked the "bad" Sony battery pack with a Dremel-powered cutoff disk. It
was stuffed with five huge prism cells, each measuring 3 x 7/8 x 1/4. At least
two of them appeared to have excessively low voltage.

I have no intention of trying to restore or replace these cells, especially as
they aren't interconnected in the way you'd expect.

The question remains... As nicads and NiMH cells are charged by constant
current (theoretically, anyway), what would cause the total post-charge
voltage to hit nearly eight volts?





== 2 of 2 ==
Date: Sat, Jan 11 2014 4:53 pm
From: John Robertson


On 01/11/2014 12:49 PM, William Sommerwerck wrote:
> I attacked the "bad" Sony battery pack with a Dremel-powered cutoff
> disk. It was stuffed with five huge prism cells, each measuring 3 x 7/8
> x 1/4. At least two of them appeared to have excessively low voltage.
>
> I have no intention of trying to restore or replace these cells,
> especially as they aren't interconnected in the way you'd expect.
>
> The question remains... As nicads and NiMH cells are charged by constant
> current (theoretically, anyway), what would cause the total post-charge
> voltage to hit nearly eight volts?

I'm no expert, but why not ask you question here:

http://batteryuniversity.com/learn/article/charging_nickel_based_batteries

I've used this site for years when I want to figure out something
battery related...

John :-#)#

--
(Please post followups or tech inquiries to the newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."





==============================================================================
TOPIC: Why use a contactor?
http://groups.google.com/group/sci.electronics.repair/t/8a277d142156dff2?hl=en
==============================================================================

== 1 of 10 ==
Date: Sat, Jan 11 2014 4:48 pm
From: DaveC


A friend (in USA) with a 220v, 1-phase horizontal bandsaw in his home machine
shop wants to replace the 1/4 hp motor with 1/2 hp and rewire with an
auto-off switch (when the blade cuts through the metal).

I always default to using a 3-wire control with contactor, but he asks the
logical question: "Why?"

Other than the "If the power fails while cutting" answer (which he says seems
of limited additional value on a saw with auto-stop feature) I wasn't very
convincing.

What are the arguments for using a contactor as opposed to a simple on-off
switch of equivalent rating?

Thanks.





== 2 of 10 ==
Date: Sat, Jan 11 2014 5:42 pm
From: "Maynard A. Philbrook Jr."


In article <0001HW.CEF726730137FDD4B01029BF@news.eternal-september.org>,
invalid@invalid.net says...
>
> A friend (in USA) with a 220v, 1-phase horizontal bandsaw in his home machine
> shop wants to replace the 1/4 hp motor with 1/2 hp and rewire with an
> auto-off switch (when the blade cuts through the metal).
>
> I always default to using a 3-wire control with contactor, but he asks the
> logical question: "Why?"
>
> Other than the "If the power fails while cutting" answer (which he says seems
> of limited additional value on a saw with auto-stop feature) I wasn't very
> convincing.
>
> What are the arguments for using a contactor as opposed to a simple on-off
> switch of equivalent rating?
>
> Thanks.


My cheap miller I use has a magnetic latch integrated into the
start/stop operator switch. it requires that you feed both the
L1 and L2 to it but only switches the L1 to the motor.

I've seen these also for three phase switching of motors so that
if you do lose power it will switch off the motor.

I guess it maybe a cost savings since it's much easier to put a
simple mechanical latch that is held with small solenoid than
putting in that extra crap.

Jamie







== 3 of 10 ==
Date: Sat, Jan 11 2014 5:49 pm
From: "Jim Wilkins"



"DaveC" <invalid@invalid.net> wrote in message
news:0001HW.CEF726730137FDD4B01029BF@news.eternal-september.org...
>A friend (in USA) with a 220v, 1-phase horizontal bandsaw in his home
>machine
> shop wants to replace the 1/4 hp motor with 1/2 hp and rewire with
> an
> auto-off switch (when the blade cuts through the metal).
>
> I always default to using a 3-wire control with contactor, but he
> asks the
> logical question: "Why?"
>
> Other than the "If the power fails while cutting" answer (which he
> says seems
> of limited additional value on a saw with auto-stop feature) I
> wasn't very
> convincing.
>
> What are the arguments for using a contactor as opposed to a simple
> on-off
> switch of equivalent rating?
>
> Thanks.

I don't remember any clear reasons for choosing one or the other from
my long-ago days designing industrial controls. IIRC at that power
level unless we needed 24V for other relays we'd go with a switch.
They can be had with two pushbuttons so you can slap the large red one
to shut it off.
http://community.woodmagazine.com/t5/image/serverpage/image-id/23197i38710354CC71A806/image-size/medium?v=mpbl-1&px=-1







== 4 of 10 ==
Date: Sat, Jan 11 2014 6:52 pm
From: DaveC


>
http://community.woodmagazine.com/t5/image/serverpage/image-
id/23197i38710354C
> C71A806/image-size/medium?v=mpbl-1&px=-1

Nice show-and-tell. Where can this switch be bought?

Thanks.





== 5 of 10 ==
Date: Sat, Jan 11 2014 7:05 pm
From: "Jim Wilkins"


"DaveC" <invalid@invalid.net> wrote in message
news:0001HW.CEF7435F013EC536B01029BF@news.eternal-september.org...
>>
> http://community.woodmagazine.com/t5/image/serverpage/image-
> id/23197i38710354C
>> C71A806/image-size/medium?v=mpbl-1&px=-1
>
> Nice show-and-tell. Where can this switch be bought?
>
> Thanks.

Here's another one I was looking at on Amazon:
http://www.amazon.com/Woodstock-D4160-110-Volt-Paddle-Switch/dp/B005W17HYY/ref=pd_sim_hi_1/191-4569239-2528519

According to the comments it latches ON magnetically, with a solenoid,
and acts like 3-wire control.
jsw






== 6 of 10 ==
Date: Sat, Jan 11 2014 7:16 pm
From: "Mike Marlow"


DaveC wrote:
> http://community.woodmagazine.com/t5/image/serverpage/image-
> id/23197i38710354C
>> C71A806/image-size/medium?v=mpbl-1&px=-1
>
> Nice show-and-tell. Where can this switch be bought?
>

Look on grizzly's web site - they sell them. I got one for my table saw and
love it.

--

-Mike-
mmarlowREMOVE@windstream.net






== 7 of 10 ==
Date: Sat, Jan 11 2014 7:19 pm
From: clare@snyder.on.ca


On Sat, 11 Jan 2014 16:48:51 -0800, DaveC <invalid@invalid.net> wrote:

>A friend (in USA) with a 220v, 1-phase horizontal bandsaw in his home machine
>shop wants to replace the 1/4 hp motor with 1/2 hp and rewire with an
>auto-off switch (when the blade cuts through the metal).
>
>I always default to using a 3-wire control with contactor, but he asks the
>logical question: "Why?"
>
>Other than the "If the power fails while cutting" answer (which he says seems
>of limited additional value on a saw with auto-stop feature) I wasn't very
>convincing.
>
>What are the arguments for using a contactor as opposed to a simple on-off
>switch of equivalent rating?
>
>Thanks.
The simplicity and safety of using low voltage controls instead of
requiring heavy duty limit switches. One adequately sized contactor
and as many microswitches as you want as controls to turn it on or
off, running at low voltage and low current.




== 8 of 10 ==
Date: Sat, Jan 11 2014 7:20 pm
From: clare@snyder.on.ca


On Sat, 11 Jan 2014 20:49:22 -0500, "Jim Wilkins"
<muratlanne@gmail.com> wrote:

>
>"DaveC" <invalid@invalid.net> wrote in message
>news:0001HW.CEF726730137FDD4B01029BF@news.eternal-september.org...
>>A friend (in USA) with a 220v, 1-phase horizontal bandsaw in his home
>>machine
>> shop wants to replace the 1/4 hp motor with 1/2 hp and rewire with
>> an
>> auto-off switch (when the blade cuts through the metal).
>>
>> I always default to using a 3-wire control with contactor, but he
>> asks the
>> logical question: "Why?"
>>
>> Other than the "If the power fails while cutting" answer (which he
>> says seems
>> of limited additional value on a saw with auto-stop feature) I
>> wasn't very
>> convincing.
>>
>> What are the arguments for using a contactor as opposed to a simple
>> on-off
>> switch of equivalent rating?
>>
>> Thanks.
>
>I don't remember any clear reasons for choosing one or the other from
>my long-ago days designing industrial controls. IIRC at that power
>level unless we needed 24V for other relays we'd go with a switch.
>They can be had with two pushbuttons so you can slap the large red one
>to shut it off.
>http://community.woodmagazine.com/t5/image/serverpage/image-id/23197i38710354CC71A806/image-size/medium?v=mpbl-1&px=-1
>
>
But if you want an auto shutoff, low voltage control to a contactor
makes it easy.




== 9 of 10 ==
Date: Sat, Jan 11 2014 7:29 pm
From: "Shaun"




"DaveC" wrote in message
news:0001HW.CEF726730137FDD4B01029BF@news.eternal-september.org...

A friend (in USA) with a 220v, 1-phase horizontal bandsaw in his home
machine
shop wants to replace the 1/4 hp motor with 1/2 hp and rewire with an
auto-off switch (when the blade cuts through the metal).

I always default to using a 3-wire control with contactor, but he asks the
logical question: "Why?"

Other than the "If the power fails while cutting" answer (which he says
seems
of limited additional value on a saw with auto-stop feature) I wasn't very
convincing.

What are the arguments for using a contactor as opposed to a simple on-off
switch of equivalent rating?

Thanks.


The reason to use a contactor instead of just an on / off switch is that the
insides of the switch can get full of saw dust and turn on the saw with the
switch in the off position. I've seen this happen!
Regular AC switches are not sealed well enough, but you can buy sealed
switches with lower current ratings which is enough to engage the contactor.

Shaun.





== 10 of 10 ==
Date: Sat, Jan 11 2014 7:44 pm
From: "Lloyd E. Sponenburgh"


clare@snyder.on.ca fired this volley in
news:a924d9t33tnjrtqblj749uprvfo3j88tpk@4ax.com:

> The simplicity and safety of using low voltage controls instead of
> requiring heavy duty limit switches. One adequately sized contactor
> and as many microswitches as you want as controls to turn it on or
> off, running at low voltage and low current.
>

Indeed, and you can add to that (if properly installed) that a contactor
will prevent accidental re-powering of equipment if it stops due to a
power failure.

With a mechanical switch, if one were to forget to turn off equipment
after a power failure, it could come on unexpectedly when power returns.

Lloyd





==============================================================================
TOPIC: 1/4" phone jack replacement for Behringer 215 speaker.
http://groups.google.com/group/sci.electronics.repair/t/0fd5e32c8baa1611?hl=en
==============================================================================

== 1 of 5 ==
Date: Sat, Jan 11 2014 5:33 pm
From: "David Farber"


This Behringer 215 speaker has two 1/4" phone jacks that are wired in
parallel. It also has two Speakon jacks wired in parallel to facilitate
adding extra speakers to the system. The unit came to me with one broken
1/4" phone jack. The picture of the pc board is here.
http://webpages.charter.net/mrfixiter/images/Electronics/Behringer/pc-board.jpg
The Speakon jacks were fastened to the back panel of the cabinet with two
screws per jack. On the other end of the screw was a nut. Unfortunately, the
nut wasn't anchored to anything so it was futile to try and remove the
screw. The circuit board prevented me from inserting any tool in there to
hold the nut while I was turning the screw. You can see the results. I
replaced the Speakon jacks, no problem.

With the help of a Mouser telephone tech to match the original part, I
ordered replacement 1/4" phone jacks, manufacturer part number NYS232.
http://www.mouser.com/ProductDetail/REAN/NYS232/?qs=%2fha2pyFadujcNYWYyUSyMSHhOqDb3buvV%252b7cmiFFRuQ%3d
The owner suggested I replaced both of them as long as I had it apart. The
parts arrived and I installed them. I wired everything back in place.
Something told me to check the input impedance of the speaker with a
multimeter just to make sure it was wired probably. It was a good thing I
did. It measured a direct short from the speaker plug input. After searching
up and down for a short, I didn't find any until I inserted the phone plug
into the jack. That's when an internal contact in the jack switched to a
different position and shorted out the plug. Ok, I guess this jack will not
work on this pc board. I called Behringer's parts department and had them
research the original part. After a day or two of researching, I received a
call back from Behringer and ordered the parts. I received the parts today.
Excited to finally get the speaker repaired, I removed the Mouser jacks and
put in the Behringer jacks, same thing. Direct short across the input
terminals. Then I looked inside and noticed there wasn't any difference in
the terminal configuration between the Mouser jack and the replacement
Behringer jack. I will call Behringer back on Monday to discuss this
situation but meanwhile, do any of you know what kind of 1/4" phone jack is
supposed to fit on this pc board?

Thanks for your reply.
--
David Farber
Los Osos, CA






== 2 of 5 ==
Date: Sat, Jan 11 2014 5:56 pm
From: "David Farber"


David Farber wrote:
> This Behringer 215 speaker has two 1/4" phone jacks that are wired in
> parallel. It also has two Speakon jacks wired in parallel to
> facilitate adding extra speakers to the system. The unit came to me
> with one broken 1/4" phone jack. The picture of the pc board is here.
> http://webpages.charter.net/mrfixiter/images/Electronics/Behringer/pc-board.jpg
> The Speakon jacks were fastened to the back panel of the cabinet with
> two screws per jack. On the other end of the screw was a nut.
> Unfortunately, the nut wasn't anchored to anything so it was futile
> to try and remove the screw. The circuit board prevented me from
> inserting any tool in there to hold the nut while I was turning the
> screw. You can see the results. I replaced the Speakon jacks, no
> problem.
> With the help of a Mouser telephone tech to match the original part, I
> ordered replacement 1/4" phone jacks, manufacturer part number NYS232.
> http://www.mouser.com/ProductDetail/REAN/NYS232/?qs=%2fha2pyFadujcNYWYyUSyMSHhOqDb3buvV%252b7cmiFFRuQ%3d
> The owner suggested I replaced both of them as long as I had it
> apart. The parts arrived and I installed them. I wired everything
> back in place. Something told me to check the input impedance of the
> speaker with a multimeter just to make sure it was wired probably. It
> was a good thing I did. It measured a direct short from the speaker
> plug input. After searching up and down for a short, I didn't find
> any until I inserted the phone plug into the jack. That's when an
> internal contact in the jack switched to a different position and
> shorted out the plug. Ok, I guess this jack will not work on this pc
> board. I called Behringer's parts department and had them research
> the original part. After a day or two of researching, I received a
> call back from Behringer and ordered the parts. I received the parts
> today. Excited to finally get the speaker repaired, I removed the
> Mouser jacks and put in the Behringer jacks, same thing. Direct short
> across the input terminals. Then I looked inside and noticed there
> wasn't any difference in the terminal configuration between the
> Mouser jack and the replacement Behringer jack. I will call Behringer
> back on Monday to discuss this situation but meanwhile, do any of you
> know what kind of 1/4" phone jack is supposed to fit on this pc
> board?
> Thanks for your reply.

Another piece of information here. If I plug in a stereo phone plug, then
there is no short circuit. Is there some industry standard to use stereo
phone plugs in this type of application? That seems a bit strange to me.

Thanks for your reply.
--
David Farber
Los Osos, CA






== 3 of 5 ==
Date: Sat, Jan 11 2014 7:37 pm
From: "Phil Allison"



"David Farber"
>
> This Behringer 215 speaker has two 1/4" phone jacks that are wired in
> parallel. It also has two Speakon jacks wired in parallel to facilitate
> adding extra speakers to the system. The unit came to me with one broken
> 1/4" phone jack. The picture of the pc board is here.
> http://webpages.charter.net/mrfixiter/images/Electronics/Behringer/pc-board.jpg
> The Speakon jacks were fastened to the back panel of the cabinet with two
> screws per jack. On the other end of the screw was a nut. Unfortunately,
> the nut wasn't anchored to anything so it was futile to try and remove the
> screw. The circuit board prevented me from inserting any tool in there to
> hold the nut while I was turning the screw.

** A small, long blade screwdriver does the trick - just wedge the tip
between the nut and the body of the Speakon to prevent it turning.

The jack sockets should be "mono" versions - stereo ones will short out as
you have found.


.... Phil










== 4 of 5 ==
Date: Sat, Jan 11 2014 7:39 pm
From: "Phil Allison"



"David Farber"

> Another piece of information here. If I plug in a stereo phone plug, then
> there is no short circuit. Is there some industry standard to use stereo
> phone plugs in this type of application?

** No way.

Mono plugs are always used for speaker leads.


.... Phil









== 5 of 5 ==
Date: Sat, Jan 11 2014 8:23 pm
From: "David Farber"


Phil Allison wrote:
> "David Farber"
>>
>> This Behringer 215 speaker has two 1/4" phone jacks that are wired in
>> parallel. It also has two Speakon jacks wired in parallel to
>> facilitate adding extra speakers to the system. The unit came to me
>> with one broken 1/4" phone jack. The picture of the pc board is here.
>> http://webpages.charter.net/mrfixiter/images/Electronics/Behringer/pc-board.jpg
>> The Speakon jacks were fastened to the back panel of the cabinet
>> with two screws per jack. On the other end of the screw was a nut.
>> Unfortunately, the nut wasn't anchored to anything so it was futile
>> to try and remove the screw. The circuit board prevented me from
>> inserting any tool in there to hold the nut while I was turning the
>> screw.
>
> ** A small, long blade screwdriver does the trick - just wedge the
> tip between the nut and the body of the Speakon to prevent it turning.
>
> The jack sockets should be "mono" versions - stereo ones will short
> out as you have found.
>
>
> .... Phil

Thanks for the confirmation of the mono plug and the trick to remove the
screw in the Speakon jack.

--
David Farber
Los Osos, CA






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

You received this message because you are subscribed to the Google Groups "sci.electronics.repair"
group.

To post to this group, visit http://groups.google.com/group/sci.electronics.repair?hl=en

To unsubscribe from this group, send email to sci.electronics.repair+unsubscribe@googlegroups.com

To change the way you get mail from this group, visit:
http://groups.google.com/group/sci.electronics.repair/subscribe?hl=en

To report abuse, send email explaining the problem to abuse@googlegroups.com

==============================================================================
Google Groups: http://groups.google.com/?hl=en