sci.electronics.repair - 25 new messages in 9 topics - digest

sci.electronics.repair
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Today's topics:

==============================================================================
TOPIC: Backiline 600
http://groups.google.com/group/sci.electronics.repair/t/21fce449cd438f07?hl=en
==============================================================================

== 1 of 1 ==
Date: Wed, Jul 14 2010 12:09 am
From: "N_Cook"

17 deg C / 0.17V of lift from a SM shottke diode under the sensor is about
right to get the fan turning properly at ambient 15 deg C or more.
Definitely a PbF solder amp from 2007. Made in China for USA for export to
the UK but presumably the same for domestic USA use , no mention of PbF on
pcb or rear of casing

==============================================================================
TOPIC: Is it just me or...
http://groups.google.com/group/sci.electronics.repair/t/406a9aeafad00ad9?hl=en
==============================================================================

== 1 of 5 ==
Date: Wed, Jul 14 2010 3:16 am
From: JW

So there you are, working on something that you don't have any schematics
for; (in this case a Datron 1281 8.5 digit DMM) This one wouldn't power
up. Poking around I noticed some (TTL) circuits were not getting +5VDC.
Traced it back through a three terminal linear regulator to it's AC input.
Hmmm... Only getting about 5.5VAC, not enough there. Isolate the AC output
from the transformer to make sure it wasn't a loading issue; it's not.
Gets to about 5.8VAC. This unit has two toroid transformers, and the one
I've traced the problem to has 8 wires on the secondary and another 8 on
the primary (sheesh)

I have no idea what the primary voltages should be (As it turns out, about
16VAC. Weird!)

BUT, suddenly I hear a metallic sounding "tick!" and the unit begins
running. (I quickly measure the primaries and note the voltages JIC.)
sounds a bit like a relay, but there's nothing like that in any of the
power supplies (there's a number of them) that I can see. Figuring an
intermittent somewhere I begin jiggling connectors, tapping around with a
screwdriver handle, etc. Nothing. Meter keeps working.

Cold blasts from freeze spray, Heat gun, etc. Nothing.

Turn it off for an hour and back on repeating what I did above. Still
working.

Turn it off for a day and back on. Wash, rinse, repeat. still working
perfectly.

Things like this seem to happen to me often. Is it just me, or do you have
faults like this that drive you nuts?

I don't suppose anyone might have any schematics for this meter, would
they? I think at some point Datron sold off to Wavetek then Fluke ended up
with it, as the user manual is available from Fluke.

Thanks.

== 2 of 5 ==
Date: Wed, Jul 14 2010 8:32 am
From: Jamie

JW wrote:

> So there you are, working on something that you don't have any schematics
> for; (in this case a Datron 1281 8.5 digit DMM) This one wouldn't power
> up. Poking around I noticed some (TTL) circuits were not getting +5VDC.
> Traced it back through a three terminal linear regulator to it's AC input.
> Hmmm... Only getting about 5.5VAC, not enough there. Isolate the AC output
> from the transformer to make sure it wasn't a loading issue; it's not.
> Gets to about 5.8VAC. This unit has two toroid transformers, and the one
> I've traced the problem to has 8 wires on the secondary and another 8 on
> the primary (sheesh)
>
> I have no idea what the primary voltages should be (As it turns out, about
> 16VAC. Weird!)
>
> BUT, suddenly I hear a metallic sounding "tick!" and the unit begins
> running. (I quickly measure the primaries and note the voltages JIC.)
> sounds a bit like a relay, but there's nothing like that in any of the
> power supplies (there's a number of them) that I can see. Figuring an
> intermittent somewhere I begin jiggling connectors, tapping around with a
> screwdriver handle, etc. Nothing. Meter keeps working.
>
> Cold blasts from freeze spray, Heat gun, etc. Nothing.
>
> Turn it off for an hour and back on repeating what I did above. Still
> working.
>
> Turn it off for a day and back on. Wash, rinse, repeat. still working
> perfectly.
>
> Things like this seem to happen to me often. Is it just me, or do you have
> faults like this that drive you nuts?
>
> I don't suppose anyone might have any schematics for this meter, would
> they? I think at some point Datron sold off to Wavetek then Fluke ended up
> with it, as the user manual is available from Fluke.
>
> Thanks.
>
>
Electrolytics will intermit like this. Change all that are in the power
supply section.

== 3 of 5 ==
Date: Wed, Jul 14 2010 8:45 am
From: stratus46@yahoo.com

On Jul 14, 8:32 am, Jamie
<jamie_ka1lpa_not_valid_after_ka1l...@charter.net> wrote:
> JW wrote:
> > So there you are, working on something that you don't have any schematics
> > for; (in this case a Datron 1281 8.5 digit DMM) This one wouldn't power
> > up. Poking around I noticed some (TTL) circuits were not getting +5VDC.
> > Traced it back through a three terminal linear regulator to it's AC input.
> > Hmmm... Only getting about 5.5VAC, not enough there. Isolate the AC output
> > from the transformer to make sure it wasn't a loading issue; it's not.
> > Gets to about 5.8VAC. This unit has two toroid transformers, and the one
> > I've traced the problem to has 8 wires on the secondary and another 8 on
> > the primary (sheesh)
>
> > I have no idea what the primary voltages should be (As it turns out, about
> > 16VAC. Weird!)
>
> > BUT, suddenly I hear a metallic sounding "tick!" and the unit begins
> > running. (I quickly measure the primaries and note the voltages JIC.)
> > sounds a bit like a relay, but there's nothing like that in any of the
> > power supplies (there's a number of them) that I can see. Figuring an
> > intermittent somewhere I begin jiggling connectors, tapping around with a
> > screwdriver handle, etc. Nothing. Meter keeps working.
>
> > Cold blasts from freeze spray, Heat gun, etc. Nothing.
>
> > Turn it off for an hour and back on repeating what I did above. Still
> > working.
>
> > Turn it off for a day and back on. Wash, rinse, repeat. still working
> > perfectly.
>
> > Things like this seem to happen to me often. Is it just me, or do you have
> > faults like this that drive you nuts?
>
> > I don't suppose anyone might have any schematics for this meter, would
> > they? I think at some point Datron sold off to Wavetek then Fluke ended up
> > with it, as the user manual is available from Fluke.
>
> > Thanks.
>
> Electrolytics will intermit like this. Change all that are in the power
> supply section.

But 'lytics do not explain the 5.8 VAC with no load.

G²

== 4 of 5 ==
Date: Wed, Jul 14 2010 9:18 am
From: Cydrome Leader

In sci.electronics.repair JW <none@dev.null> wrote:
> So there you are, working on something that you don't have any schematics
> for; (in this case a Datron 1281 8.5 digit DMM) This one wouldn't power
> up. Poking around I noticed some (TTL) circuits were not getting +5VDC.
> Traced it back through a three terminal linear regulator to it's AC input.
> Hmmm... Only getting about 5.5VAC, not enough there. Isolate the AC output
> from the transformer to make sure it wasn't a loading issue; it's not.
> Gets to about 5.8VAC. This unit has two toroid transformers, and the one
> I've traced the problem to has 8 wires on the secondary and another 8 on
> the primary (sheesh)
>
> I have no idea what the primary voltages should be (As it turns out, about
> 16VAC. Weird!)

Does this unit use an IEC type power receptable with some sort of voltage
changing/fuse module that might need to be reseated or checked?

== 5 of 5 ==
Date: Wed, Jul 14 2010 10:17 am
From: Jamie

stratus46@yahoo.com wrote:

> On Jul 14, 8:32 am, Jamie
> <jamie_ka1lpa_not_valid_after_ka1l...@charter.net> wrote:
>
>>JW wrote:
>>
>>>So there you are, working on something that you don't have any schematics
>>>for; (in this case a Datron 1281 8.5 digit DMM) This one wouldn't power
>>>up. Poking around I noticed some (TTL) circuits were not getting +5VDC.
>>>Traced it back through a three terminal linear regulator to it's AC input.
>>>Hmmm... Only getting about 5.5VAC, not enough there. Isolate the AC output
>>>from the transformer to make sure it wasn't a loading issue; it's not.
>>>Gets to about 5.8VAC. This unit has two toroid transformers, and the one
>>>I've traced the problem to has 8 wires on the secondary and another 8 on
>>>the primary (sheesh)
>>
>>>I have no idea what the primary voltages should be (As it turns out, about
>>>16VAC. Weird!)
>>
>>>BUT, suddenly I hear a metallic sounding "tick!" and the unit begins
>>>running. (I quickly measure the primaries and note the voltages JIC.)
>>>sounds a bit like a relay, but there's nothing like that in any of the
>>>power supplies (there's a number of them) that I can see. Figuring an
>>>intermittent somewhere I begin jiggling connectors, tapping around with a
>>>screwdriver handle, etc. Nothing. Meter keeps working.
>>
>>>Cold blasts from freeze spray, Heat gun, etc. Nothing.
>>
>>>Turn it off for an hour and back on repeating what I did above. Still
>>>working.
>>
>>>Turn it off for a day and back on. Wash, rinse, repeat. still working
>>>perfectly.
>>
>>>Things like this seem to happen to me often. Is it just me, or do you have
>>>faults like this that drive you nuts?
>>
>>>I don't suppose anyone might have any schematics for this meter, would
>>>they? I think at some point Datron sold off to Wavetek then Fluke ended up
>>>with it, as the user manual is available from Fluke.
>>
>>>Thanks.
>>
>>Electrolytics will intermit like this. Change all that are in the power
>>supply section.
>
>
>
> But 'lytics do not explain the 5.8 VAC with no load.
>
> G²
lets see..

~ DC = 5.8*sqrt(2) = 5.8*1.414 = 8.2;

So, with the head room required for a 5 V reg 78xx styles..
8.2-2 = 6.2 on the average.. I put in more than the normal
head room requires just to be safe on the cal's. This gives you at least
1 volt to play with...

This is all fine if you have good working caps on the device that is
giving you the DC inside, mainly the rectifier..

So, putting all that in context, I'd still be checking for the caps in
the power supply! Test the DC voltage on the input of the REG>>>>

Jamie.

==============================================================================
TOPIC: OpAmp in ZyXEL Wireless Access Point POE
http://groups.google.com/group/sci.electronics.repair/t/09422205be26f1bb?hl=en
==============================================================================

== 1 of 2 ==
Date: Wed, Jul 14 2010 4:42 am
From: AC Me

On Jul 13, 5:59 pm, Stefan Huebner <ste...@huebner-
informationselektronik.de> wrote:
> Am 13.07.2010 15:03, schrieb AC Me:
>
> > Hi all.
>
> > The Power-Over-Ethernet (POE) injector for a ZyXEL wireless network
> > link has just failed. New, or replacement, POEs are not easy to locate
> > nor is information on these devices. There is not any label or other
> > markings indicating model numbers or other information.
> > I opened the POE unit and discovered that it contains an AP34063
> > switching regulator, as would be expected, but also an LM358D (dual
> > OpAmp).
> > Does anyone have any idea why a POE unit would contain an OpAmp?
>
> To prevent injecting 40somewhat volts into an ISDN link or something
> else not aware of PoE?
> Reverse engineer the circuit, and you will not only see how it's done
> but also be able to repair this thing. Interesting enough that it uses a
> 34064, I also use lots of them :)

Thank you Stefan. That is interesting.
I have examined the unit more closely with a view to reverse
engineering it.
There seem to be a lot of components on the board and the board seems
to have more that two layers (there are few track on the top and fewer
still
on the bottom both of which are mostly copper). This looks daunting -
but
let's proceed.
First steps: How many components and what type?
I hope I haven't missed anything.
There are 2 x RJ45 through-hole sockets, 1 x DC power jack through-
hole,
2 x Electrolytics through-hole and 1 x through-hole inductor.
The surface-mount contingent consists of 4 x Zener, 2 x LED, 1 x NPN
SOT-23,
1 x NPN TO-252, 1 x Inductor, 1 x Diode, 18 x Resistor, 5 x Capacitor,
1 x
Transient Voltage Suppressor and 1 x Fuse.
.
That last component is tucked up neatly beside the 'output' (if I may
describe
it as such) RJ45 connector and is almost completely transparent. It
would
appear to be a Littlefuse 375mA device (marking of FE).
It would also appear to be blown.
And so this blown fuse might well be the problem. Now to track down a
replacement.

Thank you Stefan for your help.
By the way, are there any 'design guides', 'thoughts for a long
Winter's evening',
etc, on POEs available that would help explain these types of devices
to
an idiot like me?
I'm sure they would make interesting reading the next time I am bored.

Take care.

Mike

== 2 of 2 ==
Date: Wed, Jul 14 2010 5:13 am
From: AC Me

On Jul 14, 12:42 pm, AC Me <mmal...@gofree.indigo.ie> wrote:
> On Jul 13, 5:59 pm, Stefan Huebner <ste...@huebner-
>
>
>
> informationselektronik.de> wrote:
> > Am 13.07.2010 15:03, schrieb AC Me:
>
> > > Hi all.
>
> > > The Power-Over-Ethernet (POE) injector for a ZyXEL wireless network
> > > link has just failed. New, or replacement, POEs are not easy to locate
> > > nor is information on these devices. There is not any label or other
> > > markings indicating model numbers or other information.
> > > I opened the POE unit and discovered that it contains an AP34063
> > > switching regulator, as would be expected, but also an LM358D (dual
> > > OpAmp).
> > > Does anyone have any idea why a POE unit would contain an OpAmp?
>
> > To prevent injecting 40somewhat volts into an ISDN link or something
> > else not aware of PoE?
> > Reverse engineer the circuit, and you will not only see how it's done
> > but also be able to repair this thing. Interesting enough that it uses a
> > 34064, I also use lots of them :)
>
> Thank you Stefan. That is interesting.
> I have examined the unit more closely with a view to reverse
> engineering it.
> There seem to be a lot of components on the board and the board seems
> to have more that two layers (there are few track on the top and fewer
> still
> on the bottom both of which are mostly copper). This looks daunting -
> but
> let's proceed.
> First steps: How many components and what type?
> I hope I haven't missed anything.
> There are 2 x RJ45 through-hole sockets, 1 x DC power jack through-
> hole,
> 2 x Electrolytics through-hole and 1 x through-hole inductor.
> The surface-mount contingent consists of 4 x Zener, 2 x LED, 1 x NPN
> SOT-23,
> 1 x NPN TO-252, 1 x Inductor, 1 x Diode, 18 x Resistor, 5 x Capacitor,
> 1 x
> Transient Voltage Suppressor and 1 x Fuse.
> .
> That last component is tucked up neatly beside the 'output' (if I may
> describe
> it as such) RJ45 connector and is almost completely transparent. It
> would
> appear to be a Littlefuse 375mA device (marking of FE).
> It would also appear to be blown.
> And so this blown fuse might well be the problem. Now to track down a
> replacement.
>
> Thank you Stefan for your help.
> By the way, are there any 'design guides', 'thoughts for a long
> Winter's evening',
> etc, on POEs available that would help explain these types of devices
> to
> an idiot like me?
> I'm sure they would make interesting reading the next time I am bored.
>
> Take care.
>
> Mike

Actually, when I write POE I really mean POE Injector.

Sorry if this has caused any confusion.

Mike

==============================================================================
TOPIC: Spectrian Amplifier
http://groups.google.com/group/sci.electronics.repair/t/1090c22b48b844fb?hl=en
==============================================================================

== 1 of 7 ==
Date: Wed, Jul 14 2010 8:20 am
From: Jeffrey D Angus

Phil Allison wrote:
> "John Ferrier"
>> I have a Spectrian 30Watt 13cms power amplifier that only gives out 6Watts.
>
>
>
> ** For those curious - the unit in question is an RF power amplifier
> intended for the 2.4 GHz band.

Solid state or traveling wave tube?

Jeff

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

http://www.stay-connect.com

== 2 of 7 ==
Date: Wed, Jul 14 2010 2:46 pm
From: "Phil Allison"

"Jeffrey D Anus"
> Phil Allison wrote:
>> "John Ferrier"
>>> I have a Spectrian 30Watt 13cms power amplifier that only gives out
>>> 6Watts.
>>
>>
>>
>> ** For those curious - the unit in question is an RF power amplifier
>> intended for the 2.4 GHz band.
>
> Solid state or traveling wave tube?

** Ever heard of Google??

Dick head.

... Phil

== 3 of 7 ==
Date: Wed, Jul 14 2010 3:09 pm
From: David Nebenzahl

On 7/14/2010 2:46 PM Phil Allison spake thus:

> "Jeffrey D Anus"
>
>> Phil Allison wrote:
>>
>>> "John Ferrier"
>>>
>>>> I have a Spectrian 30Watt 13cms power amplifier that only gives out
>>>> 6Watts.
>>>
>>> ** For those curious - the unit in question is an RF power amplifier
>>> intended for the 2.4 GHz band.
>>
>> Solid state or traveling wave tube?
>
> ** Ever heard of Google??
>
> Dick head.

Phil's way of saying "I don't know"?

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

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

== 4 of 7 ==
Date: Wed, Jul 14 2010 4:45 pm
From: "Phil Allison"

"David Nebenzahl Criminal Psychopath"

>>
>>> Solid state or traveling wave tube?
>>
>> ** Ever heard of Google??
>>
>> Dick head.
>
> Phil's way of saying "I don't know"?

** I do, but will not be conned into answering a question the poster can
easily find using Google.

I expect people to know how to wipe their own arses too.

Counts fuckwits like you out.

... Phil

== 5 of 7 ==
Date: Wed, Jul 14 2010 5:21 pm
From: Jamie

Phil Allison wrote:

> "David Nebenzahl Criminal Psychopath"
>
>
>>>>Solid state or traveling wave tube?
>>>
>>>** Ever heard of Google??
>>>
>>> Dick head.
>>
>>Phil's way of saying "I don't know"?
>
>
>
> ** I do, but will not be conned into answering a question the poster can
> easily find using Google.
>
> I expect people to know how to wipe their own arses too.
>
> Counts fuckwits like you out.
>
>
> ... Phil
>
>
>
>
>
Phil, Can I offer you a Beer? it sounds like you need one!

Or maybe many!

== 6 of 7 ==
Date: Wed, Jul 14 2010 8:59 pm
From: "Michael A. Terrell"

David Nebenzahl wrote:
>
> On 7/14/2010 2:46 PM Phil Allison spake thus:
>
> > "Jeffrey D Anus"
> >
> >> Phil Allison wrote:
> >>
> >>> "John Ferrier"
> >>>
> >>>> I have a Spectrian 30Watt 13cms power amplifier that only gives out
> >>>> 6Watts.
> >>>
> >>> ** For those curious - the unit in question is an RF power amplifier
> >>> intended for the 2.4 GHz band.
> >>
> >> Solid state or traveling wave tube?
> >
> > ** Ever heard of Google??
> >
> > Dick head.
>
> Phil's way of saying "I don't know"?

He never did apologize, for killing the wild dingoes that raised him.

--
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: Wed, Jul 14 2010 9:00 pm
From: "Michael A. Terrell"

Jamie wrote:
>
> Phil Allison wrote:
>
> > "David Nebenzahl Criminal Psychopath"
> >
> >
> >>>>Solid state or traveling wave tube?
> >>>
> >>>** Ever heard of Google??
> >>>
> >>> Dick head.
> >>
> >>Phil's way of saying "I don't know"?
> >
> >
> >
> > ** I do, but will not be conned into answering a question the poster can
> > easily find using Google.
> >
> > I expect people to know how to wipe their own arses too.
> >
> > Counts fuckwits like you out.
> >
> >
> > ... Phil
> >
> >
> >
> >
> >
> Phil, Can I offer you a Beer? it sounds like you need one!
>
> Or maybe many!

Like you, he needs an attitude adjustment. :(

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

==============================================================================
TOPIC: Simple hack to get $500 to your home.
http://groups.google.com/group/sci.electronics.repair/t/6e966ec728f8678a?hl=en
==============================================================================

== 1 of 1 ==
Date: Wed, Jul 14 2010 10:15 am
From: quick money

Simple hack to get $500 to your home at http://clickandstart.co.cc

Due to high security risks,i have hidden the cheque link in an
image. in that website on left side below search box, click on image
and enter your name and address where you want to receive your
cheque.please dont tell to anyone.

==============================================================================
TOPIC: audio attenuator headphone to line
http://groups.google.com/group/sci.electronics.repair/t/b3898a02f147d683?hl=en
==============================================================================

== 1 of 2 ==
Date: Wed, Jul 14 2010 12:31 pm
From: "tg"

thanks for all the replies here. I tried a few resistor combinations (from
arfa's response) and what worked best in the end was a 22k resistor on the
positive and a 47k resistor linking the positive and the negative. I made a
cable with this setup and was able to get nice clean recordings from the
headphone socket at normal headphone volume.

== 2 of 2 ==
Date: Wed, Jul 14 2010 6:05 pm
From: "Arfa Daily"

"tg" <nospam@nospameverever.net> wrote in message
news:4c3e112d$0$28010$db0fefd9@news.zen.co.uk...
> thanks for all the replies here. I tried a few resistor combinations (from
> arfa's response) and what worked best in the end was a 22k resistor on the
> positive and a 47k resistor linking the positive and the negative. I made
> a cable with this setup and was able to get nice clean recordings from the
> headphone socket at normal headphone volume.

I'm glad what I said helped you to get a result that you were pleased with,
but I'm a little confused. Are you sure that the resistor values that you've
stated are correct, and the bottom one wasn't 4.7k rather than 47k ? As
stated, the attenuation provided would be very small - in example numbers,
1v in, around 0.7v out. With the bottom resistor at 4.7k, the attenuation
would be something over 4 : 1, which seems more realistic ?

Arfa

==============================================================================
TOPIC: Telephone wiring 101.
http://groups.google.com/group/sci.electronics.repair/t/c2d228c87bcf04bd?hl=en
==============================================================================

== 1 of 2 ==
Date: Wed, Jul 14 2010 1:02 pm
From: "David Farber"

I moved into a new house and have new voip phone service via the local cable
company. The way it's configured is the cable from outside goes into the
modem, model number Arris TM502G, then the output of the modem, labeled Tel
1/2 goes into a telephone line splitter, then the single ended part of that
splitter, goes into a telephone wall jack which is supposed to feed the rest
of the house. The third connection of the splitter goes to my Uniden
portable phone system, model EXAI3428, which I will call system #1. It works
fine.

To avoid confusion with another Uniden system, a model EXAI5688-3, I'll call
that system #2. I want to hook up system #2 at a different wall jack in
another room. When I did, there was no dial tone. System #2 was working last
week in another home so I am fairly certain that it was ok. I have a
telephone line polarity checker probably better known as, "The Fox," made by
Triplett Corporation. The l.e.d. lights up when I plug it into the back of
the modem. When I remove the telephone line from system #1 and plug in the
Fox into the splitter, it doesn't light up. I disassembled the wall jack and
sure enough, if I hook up the red test lead to the green wire and vice-versa
for the green test lead, the l.e.d. lights up. Question 1, does it make
sense that system #1 can work if the polarity is reversed? I removed the Fox
and plugged system #2 in the same jack. System #2 didn't work. Then I
reversed the red and green wires in the wall jack and tried system #2 in the
wall jack in the other room. Still no dial tone. So I disassembled the wires
in that wall jack. The wires were so snug that I could only pull it out from
the wall about 1 inch. I looked behind the jack and saw that the phone wires
were the old style red, green, yellow, black wiring. When I reversed the
wires in the wall jack back in the room where system #1 was, I noticed the
wires were a white/blue pair. I then plugged the Fox into a jack in a third
room. The Fox lit up. I plugged in system #2 into the third room and got a
dial tone. Question #2, is there a way to get the red and green wires in the
wall jack that isn't working tied into the blue/white pair at the outside
box? And finally, why does the telephone line splitter reverse the polarity?
I tried another splitter and it did the same thing.

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

== 2 of 2 ==
Date: Wed, Jul 14 2010 2:43 pm
From: greenpjs@neo.rr.com

On Wed, 14 Jul 2010 13:02:38 -0700, "David Farber"
<farberbear.unspam@aol.com> wrote:

>I moved into a new house and have new voip phone service via the local cable
>company. The way it's configured is the cable from outside goes into the
>modem, model number Arris TM502G, then the output of the modem, labeled Tel
>1/2 goes into a telephone line splitter, then the single ended part of that
>splitter, goes into a telephone wall jack which is supposed to feed the rest
>of the house. The third connection of the splitter goes to my Uniden
>portable phone system, model EXAI3428, which I will call system #1. It works
>fine.
>
>To avoid confusion with another Uniden system, a model EXAI5688-3, I'll call
>that system #2. I want to hook up system #2 at a different wall jack in
>another room. When I did, there was no dial tone. System #2 was working last
>week in another home so I am fairly certain that it was ok. I have a
>telephone line polarity checker probably better known as, "The Fox," made by
>Triplett Corporation. The l.e.d. lights up when I plug it into the back of
>the modem. When I remove the telephone line from system #1 and plug in the
>Fox into the splitter, it doesn't light up. I disassembled the wall jack and
>sure enough, if I hook up the red test lead to the green wire and vice-versa
>for the green test lead, the l.e.d. lights up. Question 1, does it make
>sense that system #1 can work if the polarity is reversed? I removed the Fox
>and plugged system #2 in the same jack. System #2 didn't work. Then I
>reversed the red and green wires in the wall jack and tried system #2 in the
>wall jack in the other room. Still no dial tone. So I disassembled the wires
>in that wall jack. The wires were so snug that I could only pull it out from
>the wall about 1 inch. I looked behind the jack and saw that the phone wires
>were the old style red, green, yellow, black wiring. When I reversed the
>wires in the wall jack back in the room where system #1 was, I noticed the
>wires were a white/blue pair. I then plugged the Fox into a jack in a third
>room. The Fox lit up. I plugged in system #2 into the third room and got a
>dial tone. Question #2, is there a way to get the red and green wires in the
>wall jack that isn't working tied into the blue/white pair at the outside
>box? And finally, why does the telephone line splitter reverse the polarity?
>I tried another splitter and it did the same thing.
>
>Thanks for your reply.
I don't think the splitter is really a splitter. My guess is it
isolates line 1 from line 2 so red/green from the cable modem goes to
one RJ11 and black/yellow goes to the other. You only have one line,
so only the first one works. Just plug a real splitter into the leg
that works. (These things aren't really splitters, but I'm using that
word because you did). Phones are connected in parallel.

==============================================================================
TOPIC: Where to get schematic of Funai TV, Model FT1371?
http://groups.google.com/group/sci.electronics.repair/t/f75b6f935b5d3675?hl=en
==============================================================================

== 1 of 4 ==
Date: Wed, Jul 14 2010 1:26 pm
From: Robert Macy

On Jul 1, 8:39 am, <jet...@bc-mung-supernet.com> wrote:
> In article <cf0e27fd-cd11-4476-bf7a-
> d07eb13a0...@y11g2000yqm.googlegroups.com>, m...@california.com says...> Anybody got one lying around?
>
> > Or at least covering the PCB on the back of the CRT neck?
>
> www.funai-corp.com
>
> --- news://freenews.netfront.net/ - complaints: n...@netfront.net ---

Thank you again for this URL, they did have a customer service contact

which replied to my request for a schematic for
Funai TV
Model FT1371
S/N V03823066
January 1998

REPLY...
Unfortunately, this set is too old.
We do not keep parts for sets as far back as 2003.
We no longer have a copy of this manual to provide you with.
My apologies for this inconvenience.
Thank you.

So, where do I get a schematic?

== 2 of 4 ==
Date: Wed, Jul 14 2010 2:10 pm
From: "William Sommerwerck"

> We do not keep parts for sets as far back as 2003.

That's illegal. Unless Federal law has changed. Which it might have. It used
to be 10 years.

== 3 of 4 ==
Date: Wed, Jul 14 2010 2:56 pm
From: Robert Macy

On Jul 14, 2:10 pm, "William Sommerwerck" <grizzledgee...@comcast.net>
wrote:
> > We do not keep parts for sets as far back as 2003.
>
> That's illegal. Unless Federal law has changed. Which it might have. It used
> to be 10 years.

Will check.

However, tax records kept 3 years, most statute of limitations are 7
years, legally declared dead after missing,7 years.

Maybe it is 7 years.

== 4 of 4 ==
Date: Wed, Jul 14 2010 9:04 pm
From: "Michael A. Terrell"

William Sommerwerck wrote:
>
> > We do not keep parts for sets as far back as 2003.
>
> That's illegal. Unless Federal law has changed. Which it might have. It used
> to be 10 years.

Funai isn't an American company. A lot of imported crap never had
repair parts availible in the US. that's one of many reasons why they
can sell so cheap. :(

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

==============================================================================
TOPIC: Stephen Wolfram's book, "A New Kind of Science" gives us three (3) very
important facts:
http://groups.google.com/group/sci.electronics.repair/t/23ad6e1c24cad583?hl=en
==============================================================================

== 1 of 1 ==
Date: Wed, Jul 14 2010 7:27 pm
From: fitz

Stephen Wolfram's book, "A New Kind of Science" gives us three (3)
very important facts:

1. Mathematics can only explain simple things.

2. You need a model to explain complicated things.

3. But - a simple model can explain complicated things.

It looks to me like we have a PHASE model here.

"in phase attract"

Type those three words - above - into Google (Include quote marks) to
learn not only the basics of electricity but how all the fundamental
forces work.

Or click the following link that will give you the same page in
Google. http://www.google.com/search?hl=en&source=hp&q=%22in+phase+attract%22&btnG=Google+Search

Not only do all electric motors obey these phase laws but this entire
universe seems to as well.

(Click link below.)
http://www.amperefitz.com/in.phase.attract.htm

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