sci.electronics.repair - 25 new messages in 8 topics - digest

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

sci.electronics.repair@googlegroups.com

Today's topics:

==============================================================================
TOPIC: Guitar Pickups Coil Ringing Test Electric Testing PUP
http://groups.google.com/group/sci.electronics.repair/t/3f84b39bfef04db0?hl=en
==============================================================================

== 1 of 2 ==
Date: Mon, Jun 20 2011 12:08 am
From: "Wild_Bill"

I attempted to explain that I've disassembled the humbucker pickup,
separated the 2 coils, and have removed all the metal influences from the
coils.
The magnet, pole pieces, screws, frame plate and cover have been removed and
set aside.

Just a plastic bobbin and hundreds of turns of wire.. there is no metal,
other than the coil of wire.
The desk where I'm checking the coils is wood.

At that point, there weren't even any long signal leads attached to the
coil.

So I've reassembled the pickup as originally wired, with a short pigtail of
shielded pickup coil cable.

I added an inline 1/4" jack to the pigtail, and plugged my VOX AM30 Amplug
headphone amplifier into the pigtail, and held the pickup near the guitar
strings (in the open space between the guitar's neck and bridge pickups..

and Buhh-Zinga! plenty of output from this Epiphone humbucker pickup.

This isn't a definitive performance test, but the notes sound very clear and
strong for all the strings.
I immediately plugged the H-P amp into the guitar, and the Epiphone pickup
sounded essentially the same as the guitar's DiMarzio DP155 bridge pickup.

I hadn't suspected that the Epiphone pickup was bad, but I wasn't sure since
it hadn't been installed in a guitar since I've had it.

BTW, I didn't place the metal cover back on the pickup, and I'm aware that a
metal cover will create a fairly large area for eddy current to pass, and
slightly affect the peak frequency.

I think I'll make a little gantry for suspending test pickups over the
guitar strings, for a quick bench check.

But I still don't know why the Bare coils didn't ring higher than 4 rings.
It's possible that shorted turns could exist even though the output seems to
be OK.

Oh, and forgot to mench.. the inductance measurement for the combined coils
in this pickup (when it's fully assembled) reads about 5.5 H.

--
Cheers,
WB
.............

"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:967oqaFks6U1@mid.individual.net...
>
> "Wild_Bill"
>>
>> I remembered that the Z-Meter manuals specifically state that these
>> testers work with inductors with powdered iron/ferrite-type cores (not
>> steel such as power transformers), so I removed the steel screws, but the
>> coils still only have 4 rings.
>
>
> ** The pickup has a steel ( possibly Alnico ) magnet and soft iron pole
> pieces, this makes for a lossy inductor - bit like a normal loudspeaker
> voice coil is.
>
> If you remove all of that, the inductance goes down and you have a low Q
> inductor because of the high resistance.
>
>
> ... Phil
>
>
>
>
>

== 2 of 2 ==
Date: Mon, Jun 20 2011 8:38 am
From: "hrhofmann@att.net"

On Jun 20, 2:08 am, "Wild_Bill" <wb_wildb...@XSPAMyahoo.com> wrote:
> I attempted to explain that I've disassembled the humbucker pickup,
> separated the 2 coils, and have removed all the metal influences from the
> coils.
> The magnet, pole pieces, screws, frame plate and cover have been removed and
> set aside.
>
> Just a plastic bobbin and hundreds of turns of wire.. there is no metal,
> other than the coil of wire.
> The desk where I'm checking the coils is wood.
>
> At that point, there weren't even any long signal leads attached to the
> coil.
>
> So I've reassembled the pickup as originally wired, with a short pigtail of
> shielded pickup coil cable.
>
> I added an inline 1/4" jack to the pigtail, and plugged my VOX AM30 Amplug
> headphone amplifier into the pigtail, and held the pickup near the guitar
> strings (in the open space between the guitar's neck and bridge pickups..
>
> and Buhh-Zinga! plenty of output from this Epiphone humbucker pickup.
>
> This isn't a definitive performance test, but the notes sound very clear and
> strong for all the strings.
> I immediately plugged the H-P amp into the guitar, and the Epiphone pickup
> sounded essentially the same as the guitar's DiMarzio DP155 bridge pickup.
>
> I hadn't suspected that the Epiphone pickup was bad, but I wasn't sure since
> it hadn't been installed in a guitar since I've had it.
>
> BTW, I didn't place the metal cover back on the pickup, and I'm aware that a
> metal cover will create a fairly large area for eddy current to pass, and
> slightly affect the peak frequency.
>
> I think I'll make a little gantry for suspending test pickups over the
> guitar strings, for a quick bench check.
>
> But I still don't know why the Bare coils didn't ring higher than 4 rings.
> It's possible that shorted turns could exist even though the output seems to
> be OK.
>
> Oh, and forgot to mench.. the inductance measurement for the combined coils
> in this pickup (when it's fully assembled) reads about 5.5 H.
>
> --
> Cheers,
> WB
> .............
>
> "Phil Allison" <phi...@tpg.com.au> wrote in message
>
> news:967oqaFks6U1@mid.individual.net...
>
>
>
>
>
> > "Wild_Bill"
>
> >> I remembered that the Z-Meter manuals specifically state that these
> >> testers work with inductors with powdered iron/ferrite-type cores (not
> >> steel such as power transformers), so I removed the steel screws, but the
> >> coils still only have 4 rings.
>
> > ** The pickup has a steel ( possibly Alnico ) magnet and soft iron pole
> > pieces, this makes for a lossy inductor - bit like a normal loudspeaker
> > voice coil is.
>
> > If you remove all of that, the inductance goes down and you have a low Q
> > inductor because of the high resistance.
>
> > ... Phil- Hide quoted text -
>
> - Show quoted text -

Because the inductance of the coil alone is VERY much smaller than the
inductance when it is placed inside the pole pieces, while the
resistance of the coil does not change. Thus the Q changes
drastically because the ratio of inductance to resistance changes
radically.

==============================================================================
TOPIC: misted C electrolyte
http://groups.google.com/group/sci.electronics.repair/t/c9c9924698735c42?hl=en
==============================================================================

== 1 of 4 ==
Date: Mon, Jun 20 2011 3:36 am
From: "N_Cook"

I reckon the "electrolyte" is kitchen fat. I saked the owner if used in a
kitchen and he said no. But it was used in a caravan which was used for
cooking in. So tried tasting somer on the tip of my tongue and swilling off
soon after. No sweetness , if anything cooking fat taste. Checked my taste
buds with some glycerin and distinct sweet taste. No problems with cracked
tops , ESR or capacity with the removed and then replaced caps.

Cleaned the main board with meths , dried for an hour or so and same
symptoms.
Cleaned the ps and inverter board , dried for only 10 minutes and ps went
into protect.
Dried with hot air and pic flashed up for 1/10 sec or so. Concentrated
heating on the 6 inch long strip of isolated track along the pcb edge to one
of the backlight connectors and now about 1/3 second. Previously about 1
second when I eceived the TV.
Agrees with the owner in that when this problem fisst appeared someone
technical decided to run a hair drier in the top and it ran perfectly on for
a week or so.
Yesterday I picked up at a hamfest a range of 1G to 1T ohm resistors
coincidently. I reckon its a glass fibre osmotic problem and HV , like I've
seen on scope tripler/quint boards over the years.
Will try cutting those long lines and HV cable bridged there instead.
There must be another control line back from the inverter protect system,
back to the main control and then back out to the backlight control to the
inverter.
If this is the failure mechanism then presumably a generic problem for this
sort of long pcb trace to a backlight connector and then cable proper.
Will have to see if there are reports of this problem and delve into
backlight inverter control a bit more.

Again generally, comparing a 15 inch LCD TV to 30 inch. Obviously the
inverter and lights would be x4 power but would anything else in the
electronics be much different?

== 2 of 4 ==
Date: Mon, Jun 20 2011 4:47 am
From: "N_Cook"

problem was with the 3 small 3Kv rated blue ceramic caps at the inverter
output. First variation between this Goodmans and the Toshiba schematic.
Overlay numbering the same , 3KV the same but 3x 5pF on the Toshiba and 2
marked 12 presumably 12pF and one 4.7 presumably 4.7pF. Now to find dome 5KV
rated ones.
Disconnected them and powered up for long enough to get the display on for
some 20 seconds and blue screen with annunciators etc before I decided to
switch off and find some replacements

== 3 of 4 ==
Date: Mon, Jun 20 2011 5:58 am
From: "Phil Allison"

"Nutcase FUCKING KOOK "
>
>
>I reckon the "electrolyte" is kitchen fat. I saked the owner if used in a
> kitchen and he said no. But it was used in a caravan which was used for
> cooking in. So tried tasting somer on the tip of my tongue and swilling
> off
> soon after. No sweetness , if anything cooking fat taste. Checked my taste
> buds with some glycerin and distinct sweet taste. No problems with cracked
> toor capacity with the removed and then replaced caps.

** Quote:

" LCD TV SMPS LV C vented electrolyte, "

What Low Voltage Cap was that - eh ??????

You fucking LIED to us - AGAIN !!!!!!

You FUCKING MORON !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

... Phil

== 4 of 4 ==
Date: Mon, Jun 20 2011 9:02 am
From: "N_Cook"

found a number of 22pF 3KV and seriesed them up , working fine now

==============================================================================
TOPIC: Blocking 425-336-8351 Robot Caller Parasite
http://groups.google.com/group/sci.electronics.repair/t/ed4180d1215897c7?hl=en
==============================================================================

== 1 of 2 ==
Date: Mon, Jun 20 2011 4:18 am
From: Bruce Esquibel

Wild_Bill <wb_wildbill@xspamyahoo.com> wrote:
> I was gonna mench, there was a device marketed in the 80s, I think, that
> wouldn't even ring your phone until the caller entered a 3-digit number.. it
> might'a been the AES company.

> No outgoing message, that I recall, it required all callers to know the
> owner, and call from a touchtone phone, IIRC.
> Maybe it was before the 80s.. quite a while before caller ID was available.

Privcode, if thats the same one you are thinking of.

I had two of them, worked great. For that time period it was a well thought
out device. If they didn't have a touch tone phone to punch in the code (you
could issue up to 16 different ones, I think), it would start to speak the
numbers (one, two, three...) and the caller could say "stop".

There was like one dummy code to hand out, would just ring for the caller,
wouldn't ring the phone on your end. 123 always went straight to the
answering machine.

Even came with a deck of cards you could write out the code number issued,
along with the instructions for the caller about how to get in.

Best feature was, it intercepted the incoming call. If someone dialed the
number and had no code, end of story, never rang your phone.

Biggest problem with them was with lighting strikes, even a near-by one
seemed to blow the unit, not a direct hit either. Kinda pricey for the time,
was either like $600 or $800 in late 1980's dollars.

I think the common place caller-id and cheap digital answering machines
killed off the company, but that really was a great device.

-bruce
bje@ripco.com

== 2 of 2 ==
Date: Mon, Jun 20 2011 12:50 pm
From: Meat Plow

On Sat, 18 Jun 2011 22:54:04 +0000, Geoffrey S. Mendelson wrote:

> Meat Plow wrote:
>> Now my mom has digital phone on cable and she gets several of these
>> calls every day. She ignores them if she doesn't recognize the caller
>> ID. Before she switched to digital phone she seldom got telemarketing
>> calls. I think the cable company got hacked into and phone numbers were
>> stolen and they never told anyone. My girlfriend also has digital phone
>> from the same cable provider and she gets telemarketing calls all day
>> long. I asked her if she was plagued with these calls with a
>> traditional land line with the same number and she said no. This
>> bolsters my thinking there was a breech in the cable company's security
>> or maybe they just flat out sold a list of numbers. Of course they
>> would never admit to either the numerous times I've talked to them at
>> their main office.
>
> Do they have a unique prefix? Here the landline numbers are
> 02,03,04,06,08,09, cell phones 05 and the various secondary landline
> (e.g. cable, DSL remarketers, etc are 07).
>
> Cell phones cost a lot to call, landlines less and the secondary
> provider landlines are very cheap.
>
> Although you can port a number from one to others, no one seems to
> notice. :-)
>
> Maybe they have a similar setup and call the cable phone numbers hoping
> to get a hit without having a list.
>
> BTW, one way you can get around this is if you live in the US is to use
> Google voice. You can program in a list of numbers to forward, numbers
> to reject, numbers to go to voice mail and numbers to screen (ask for
> name).
>
> Another is with a SKYPE incoming number. I cheat and have my incoming
> voicemail message the old three tone pattern which tells an autodialer
> its a dead number. :-) Once you get a call from a number, you can select
> block this number and they get a number not in service error if they
> call you.
>
> I wish there was a realtime black hole list for asterisk systems
> (freeware PBX software) like there is for SPAM email addresses. I.E.
> your asterisk system would check a database of SPAM callers and reject
> the call, with someone maintining a global list.
>
> Geoff.

Yeah, no prefixes here to distinguish between land, dsl, cable, or cell.
My mom has a decent caller blocking system, I just need to get over there
and program it for her.

--
Live Fast Die Young, Leave A Pretty Corpse

==============================================================================
TOPIC: SAMSUNG Power problem LN40A530
http://groups.google.com/group/sci.electronics.repair/t/e93c31635d90d67f?hl=en
==============================================================================

== 1 of 1 ==
Date: Mon, Jun 20 2011 4:27 am
From: benitos

On Jun 19, 4:25 pm, PlainB...@yawhoo.com wrote:
> On Sat, 18 Jun 2011 19:50:26 -0700 (PDT), benitos <poth...@cae.ca>
> wrote:
>
>
>
>
>
> >On 17 juin, 15:37, PlainB...@yawhoo.com wrote:
> >> On Thu, 16 Jun 2011 10:16:53 -0700 (PDT), benitos <poth...@cae.ca>
> >> wrote:
>
> >> >Hi having a SAMSUNG LN40A530P1 television that takes very long time to
> >> >get an image /sound.
>
> >> >After checking the capacitors on the power supply board , there is no
> >> >"pop-up" on the top and they all mesured good (value & ESR).
>
> >> >I check on the web and many people are talking about the 1000uF/10V
> >> >that are border line , should be rate at 16V instead of 10V but
> >> >again , they seem to be good.
>
> >> >Any idea ?
>
> >> It may not be a problem with the power supply itself. Most TVs have a
> >> mixture of LDO analog and bucking (PWM) regulators on the main board.
> >> This might be a bad LDO regulator, but it's far more likely that it's
> >> a bad cap on the output of a bucking regulator.
>
> >> PlainBill
>
> >Are you talking about the board with all the input RCA jacks , doesn`t
> >seem to have any caps on this board.
>
> >Or is it the board with all the connections for the LAMP .
>
> >On this unit , there are the power supply , input and inverter board.
>
> >Thanks
>
> Believe me, there are caps on the main board, and voltage regulators.
> You may not recognize them, but they are there.
>
> PlainBill- Hide quoted text -
>
> - Show quoted text -

Main board means where all the inputs are (HDMI , RCA , etc...) ?

==============================================================================
TOPIC: OT -- switching heating elements
http://groups.google.com/group/sci.electronics.repair/t/2359de19aee3537a?hl=en
==============================================================================

== 1 of 11 ==
Date: Mon, Jun 20 2011 5:44 am
From: "William Sommerwerck"

"spamtrap1888" <spamtrap1888@gmail.com> wrote in message
news:46d71b8a-ea16-41d8-b274-219d03f80a3e@22g2000prx.googlegroups.com...
On Jun 19, 5:14 pm, "William Sommerwerck" <grizzledgee...@comcast.net>
wrote:
> "klem kedidelhopper" <captainvideo462...@gmail.com> wrote in message
> news:c57a5c52-9fa3-44b0-9d97-2d4c08bf27f6@dq9g2000vbb.googlegroups.com...

>>>> You don't have to take off the back of the oven. You can remove the
>>>> element in situ. Just undo two 1/4" hex-head screws, pull out the base
>>>> of the element a bit, and pull off the friction-fit connectors.

>>> Well, at least one side of the line is disconnected.

>> If both sides were connected, the element would be on! Wouldn't it?

> But you wouldn't be replacing the element if it was on, right?

Correct. But you said "Well, at least one side of the line is disconnected".

== 2 of 11 ==
Date: Mon, Jun 20 2011 5:55 am
From: klem kedidelhopper

On Jun 19, 8:14 pm, "William Sommerwerck" <grizzledgee...@comcast.net>
wrote:
> "klem kedidelhopper" <captainvideo462...@gmail.com> wrote in message
>
> news:c57a5c52-9fa3-44b0-9d97-2d4c08bf27f6@dq9g2000vbb.googlegroups.com...
>
> >> You don't have to take off the back of the oven. You can remove the
> >> element in situ. Just undo two 1/4" hex-head screws, pull out the base
> >> of the element a bit, and pull off the friction-fit connectors.
> > Well at least one side of the line is disconnected.
>
> If both sides were connected, the element would be on! Wouldn't it?
>
> > Thank God for small favors. So when you reach inside the oven
> > and pull the hot terminal off the element while you're leaning on
> > the open door with your chest, you only pass 120 through you heart.
>
> Well, I was clothed. And the door was off.

Someone is saving a buck. There must be money involved somehow. It's
the least common denominator. It always is.
Lenny

== 3 of 11 ==
Date: Mon, Jun 20 2011 6:10 am
From: "William Sommerwerck"

"klem kedidelhopper" <captainvideo462009@gmail.com> wrote in message
news:87dc74d5-a347-4fc4-bf8e-3950d6044d43@a31g2000vbt.googlegroups.com...

> Someone is saving a buck. There must be money involved somehow.
> It's the least common denominator. It always is.

As someone said... "Don't assume conspiracies when simple stupidity is
enough to explain something."

== 4 of 11 ==
Date: Mon, Jun 20 2011 7:29 am
From: Jeffrey Angus

On 6/20/2011 8:10 AM, William Sommerwerck wrote:
> "klem kedidelhopper"<captainvideo462009@gmail.com> wrote in message
> news:87dc74d5-a347-4fc4-bf8e-3950d6044d43@a31g2000vbt.googlegroups.com...
>
>> Someone is saving a buck. There must be money involved somehow.
>> It's the least common denominator. It always is.
>
> As someone said... "Don't assume conspiracies when simple stupidity is
> enough to explain something."
>
>

It's a series circuit, it only take ONE switch to open it.
There is absolutely NO reason to use a dual pole switch.

I'm tired of hearing "It's the evil corporations" being at fault
for people that can't or won't pay attention when doing their
own repairs and try to shift the blame from their own carelessness.

Jeff

--
"Everything from Crackers to Coffins"

== 5 of 11 ==
Date: Mon, Jun 20 2011 7:38 am
From: Smitty Two

In article <itngtl$goc$1@dont-email.me>,
"William Sommerwerck" <grizzledgeezer@comcast.net> wrote:

>
> As someone said... "Don't assume conspiracies when simple stupidity is
> enough to explain something."

I thought you were going to drop this thread, but since your words and
actions don't match, I'll agree with others who've opined that you're
the stupid one here, working on a 240 volt system with it plugged in.

== 6 of 11 ==
Date: Mon, Jun 20 2011 9:43 am
From: "William Sommerwerck"

"Jeffrey Angus" <jangus@suddenlink.net> wrote in message
news:itnlgj$hhu$1@dont-email.me...
> On 6/20/2011 8:10 AM, William Sommerwerck wrote:
> > "klem kedidelhopper"<captainvideo462009@gmail.com> wrote in message
> >
news:87dc74d5-a347-4fc4-bf8e-3950d6044d43@a31g2000vbt.googlegroups.com...

>>> Someone is saving a buck. There must be money involved somehow.
>>> It's the least common denominator. It always is.

>> As someone said... "Don't assume conspiracies when simple stupidity is
>> enough to explain something."

> It's a series circuit, it only take ONE switch to open it.
> There is absolutely NO reason to use a dual pole switch.

I'm sorry, but you're wrong -- probably because you aren't familiar with
American wiring.

The standard line voltage in North America is 120V (or thereabouts). Most
houses are wired to two "phases" (or whatever the correct term is). When
higher voltage is needed -- for a dryer, range, or water heater -- the
device is connected across these phases, producing a net voltage of around
210V.

Now, if you connect /either/ of these phases to the neutral, current will
flow. This is what happened when I moved the element -- it banged into the
neutral (the oven wall itself, presumably), and tripped the breaker.

As someone else pointed out, my range and other GE ranges have one side of
the baking and broiling elements permanently connected to one of the phases,
making them /live/ as long as the breaker is connected. There is no reason
for this, other than saving a dollar or two manufacturing costs.

> I'm tired of hearing "It's the evil corporations" being at fault
> for people that can't or won't pay attention when doing their
> own repairs and try to shift the blame from their own carelessness.

I spoke with a customer-service rep at GE this morning, who agreed that
switching only one side of the line was potentially (pun intended?)
dangerous. Think of an oven in a flooded basement.

== 7 of 11 ==
Date: Mon, Jun 20 2011 9:43 am
From: "William Sommerwerck"

"Smitty Two" <prestwhich@earthlink.net> wrote in message
news:prestwhich-8F3795.07383820062011@news.eternal-september.org...
> In article <itngtl$goc$1@dont-email.me>,
> "William Sommerwerck" <grizzledgeezer@comcast.net> wrote:

>> As someone said... "Don't assume conspiracies when simple stupidity is
>> enough to explain something."

> I thought you were going to drop this thread, but since your words and
> actions don't match, I'll agree with others who've opined that you're
> the stupid one here, working on a 240 volt system with it plugged in.

I was, but people kept responding.

== 8 of 11 ==
Date: Mon, Jun 20 2011 4:27 pm
From: Jeffrey Angus

On 6/20/2011 11:43 AM, William Sommerwerck wrote:
> "Jeffrey Angus"<jangus@suddenlink.net> wrote in message
>
>> It's a series circuit, it only take ONE switch to open it.
>> There is absolutely NO reason to use a dual pole switch.
>
> I'm sorry, but you're wrong -- probably because you aren't familiar with
> American wiring.
>
> The standard line voltage in North America is 120V (or thereabouts). Most
> houses are wired to two "phases" (or whatever the correct term is). When
> higher voltage is needed -- for a dryer, range, or water heater -- the
> device is connected across these phases, producing a net voltage of around
> 210V.
>
> Now, if you connect /either/ of these phases to the neutral, current will
> flow. This is what happened when I moved the element -- it banged into the
> neutral (the oven wall itself, presumably), and tripped the breaker.
>
> As someone else pointed out, my range and other GE ranges have one side of
> the baking and broiling elements permanently connected to one of the phases,
> making them /live/ as long as the breaker is connected. There is no reason
> for this, other than saving a dollar or two manufacturing costs.

And in short (pun intended) you were using it wrong.
Under normal operation there is absolutely no reason what so ever
for one or the other side to go to neutral.

>> I'm tired of hearing "It's the evil corporations" being at fault
>> for people that can't or won't pay attention when doing their
>> own repairs and try to shift the blame from their own carelessness.
>
> I spoke with a customer-service rep at GE this morning, who agreed that
> switching only one side of the line was potentially (pun intended?)
> dangerous. Think of an oven in a flooded basement.

The cabinet is supposed to be grounded.

This isn't like the classic "All the wiring is floating" toaster in the
bath tub trick.

And if you're foolish enough to try using an electrical oven (or any
other electrical appliance) in a flooded basement, you deserve anything
that happens to you.

Jeff

--
"Everything from Crackers to Coffins"

== 9 of 11 ==
Date: Mon, Jun 20 2011 4:48 pm
From: Jeffrey Angus

By the way, on page 3 of the users manual for the GE JBP64
it makes a couple of interesting statements.

1. Make sure you appliance is properly installed and GROUNDED.
2. Before performing any service, disconnect the range power
supply at the household distribution panel by removing the
fuse or switching off the circuit breaker.

But what I find really interesting...

"Do not attempt to repair or replace any part of your range
unless is specifically recommended in the manual. All other
servicing should be referred to a qualified technician."

The user manual goes on to tell you how to clean it, and how
to change the light bulb in the oven. NOWHERE does it tell you
to replace the burner elements.

So which part of the manual did you think did not apply to
you?

Well, William, wanna give it another go at how you're the
victim here of a corporation's greed?

Remember, it ONLY takes ONE switch to OPEN a series circuit.
That is ALL that is required to control whether or not the
element gets hot or cools off.

Oh and by the way, since you brought it up, the bit about
both of the 240 volt sources being "hot with respect to
neutral". The heating elements are connected ACROSS the 240
VAC source, NOT split with each half going from the two
sources to neutral. (That would require a double contact to
turn each PAIR of heating elements on and off.)

"Removing power" on the other hand is accomplished, per the
manual, by turning off the source. (And yes, that turns off
BOTH sides of the 240 VAC supply.)

Jeff

--
"Everything from Crackers to Coffins"

== 10 of 11 ==
Date: Mon, Jun 20 2011 5:06 pm
From: "William Sommerwerck"

> "Jeffrey Angus"<jangus@suddenlink.net> wrote in message

> The cabinet is supposed to be grounded. This isn't like the classic
> "All the wiring is floating" toaster in the bath tub trick.

I'm not sure about that. I think there is a similarity. "Mythbusters" showed
that someone /can/ be electrocuted when a heater or toaster is tossed into a
bathtub.

> And if you're foolish enough to try using an electrical oven (or any other
> electrical appliance) in a flooded basement, you deserve anything that
> happens to you.

Of course! But what would happen if someone waded into the flooded basement
to shut off the breakers (which is what I was thinking of)? If the water
were high enough to enter the oven cavity, the water would be "hot".

I agree that no one should enter a flooded room without wearing waterproof
rubber boots, but... Many possible accidents -- however unlikely -- are
/predictable/. Why not avoid them in the first place, especially when it
adds next to nothing to the cost of the appliance?

Many years ago, my father was using a metal-bodied electric drill in the
basement. He was wearing leather-soled shoes and standing on concrete, which
(as it is in many basements) was faintly damp. The drill's motor shorted out
to the metal body, and he was nearly electrocuted. This was before
double-insulated tools, and outside of not standing on a thick rubber mat, *
he was doing nothing wrong. At least, not by the standards of the day.

In the US, new construction requires GFI outlets near sinks or other water
supplies.

* Black rubber objects often contain carbon, which is more conductive than
you might think. I discovered this more than 30 years ago when trying to use
rubber washers to insulate rack-mount equipment.

== 11 of 11 ==
Date: Mon, Jun 20 2011 5:16 pm
From: "William Sommerwerck"

"Jeffrey Angus" <jangus@suddenlink.net> wrote in message
news:itom8d$233$1@dont-email.me...

> By the way, on page 3 of the users manual for the GE JBP64
> it makes a couple of interesting statements.

> 1. Make sure you appliance is properly installed and GROUNDED.
> 2. Before performing any service, disconnect the range power
> supply at the household distribution panel by removing the
> fuse or switching off the circuit breaker.

> But what I find really interesting...
> "Do not attempt to repair or replace any part of your range
> unless is specifically recommended in the manual. All other
> servicing should be referred to a qualified technician."

I am an qualified technician -- despite what you might think.

> Well, William, wanna give it another go at how you're the
> victim here of a corporation's greed?

I'm not anybody's victim.

> Remember, it ONLY takes ONE switch to OPEN a series circuit.
> That is ALL that is required to control whether or not the
> element gets hot or cools off.

You were not paying attention! Any heating device that uses both "phases"
requres TWO switches to open it.

> Oh, and by the way, since you brought it up, the bit about
> both of the 240 volt sources being "hot with respect to
> neutral". The heating elements are connected ACROSS the 240
> VAC source, NOT split with each half going from the two
> sources to neutral. (That would require a double contact to
> turn each PAIR of heating elements on and off.)

I'm not sure what you're talking about. First, there is no "240V" source in
my condo. There are multiple 120V sources from which you can get higher
voltages by spanning them. (I assume each voltage is referenced to some
"neutral" point.) In my preceding apartment, I took advantage of this to
build a break-out box -- all to code, I have several electrician friends who
advised me -- to provide individual lines for my class A power amps.

As someone else kindly pointed out, this oven has one side of its elements
hard-wired to AC. Bad, bad, bad, bad idea.

==============================================================================
TOPIC: panasonic DC280-340V Dc Motor
http://groups.google.com/group/sci.electronics.repair/t/b4bd99989e15505b?hl=en
==============================================================================

== 1 of 1 ==
Date: Mon, Jun 20 2011 12:21 pm
From: kwamena banson

I have a panasonic ARW4 1H8P30AC
SP 30W DC280-340V
A981 149 (The above is the label on the
motor)
DC motor which I had from an Air conditioner. I want to use it for a
project but i can't figure out how to start it.
it has 5 leads in the ff colors Red, Back, White, Yellow and Blue.
Any information on how to start this Motor will be of great help to
me. Thanks

==============================================================================
TOPIC: Sony STR DA555ES dead
http://groups.google.com/group/sci.electronics.repair/t/5f834024d11b2b0f?hl=en
==============================================================================

== 1 of 3 ==
Date: Mon, Jun 20 2011 2:05 pm
From: klem kedidelhopper

This is a high end, (well 12 years ago) surround receiver that was
given to me dead. There is no relay click and all fuses are good. The
power transformer is not open. I would like to give this to my son who
needs a surround receiver for the addition he just put on his house. I
suspect a problem in the control circuit but the way this thing is
built I'm really lost without a schematic. Does anyone have a service
manual or at least perhaps a schematic for this unit? Thanks,Lenny

== 2 of 3 ==
Date: Mon, Jun 20 2011 3:56 pm
From: Franc Zabkar

On Mon, 20 Jun 2011 14:05:06 -0700 (PDT), klem kedidelhopper
<captainvideo462009@gmail.com> put finger to keyboard and composed:

>Does anyone have a service
>manual or at least perhaps a schematic for this unit?

http://www.promelec.ru/UPLOAD/xml/scheme/STR-DA333_555ES.pdf

FYI, you can filter your Google searches as follows:
http://www.google.com/search?q=%22STR+DA555ES%22+filetype%3Apdf+OR+filetype%3Adoc+%22service+manual%22

The service manual is also available at ...
http://elektrotanya.com

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

== 3 of 3 ==
Date: Mon, Jun 20 2011 4:19 pm
From: klem kedidelhopper

On Jun 20, 6:56 pm, Franc Zabkar <fzab...@iinternode.on.net> wrote:
> On Mon, 20 Jun 2011 14:05:06 -0700 (PDT), klem kedidelhopper
> <captainvideo462...@gmail.com> put finger to keyboard and composed:
>
> >Does anyone have a service
> >manual or at least perhaps a schematic for this unit?
>
> http://www.promelec.ru/UPLOAD/xml/scheme/STR-DA333_555ES.pdf
>
> FYI, you can filter your Google searches as follows:http://www.google.com/search?q=%22STR+DA555ES%22+filetype%3Apdf+OR+fi...
>
> The service manual is also available at ...http://elektrotanya.com
>
> - Franc Zabkar
> --
> Please remove one 'i' from my address when replying by email.

Thanks for the reply. I actually found one at no charge on
hifiengine.com Lenny

==============================================================================
TOPIC: flyback
http://groups.google.com/group/sci.electronics.repair/t/273b5787d226bb6e?hl=en
==============================================================================

== 1 of 1 ==
Date: Mon, Jun 20 2011 3:32 pm
From: John-Del

On Jun 19, 7:16 pm, John-Del <ohge...@aol.com> wrote:
> On Jun 18, 4:36 pm, "Vince Schmitt" <vschmit...@gmail.com> wrote:
>
> > Hi!
> > I need to know the draw # for a flyback transformer for an RCA Chassis
> > CTC203AAA9.
> > Thank yoy
> > Vince
>
> Database shows part number 244229 for your chassis version, but TCE
> TVs have had issues with the numbers on the original fly needing to be
> researched. Do you have the original and are the numbers legible?
>
> John

An older RCA part program (back when RCA was actually a viable
company) shows a DRAWING number (the number actually on the fly) of
XX15361-19A That number is only useful if you're scrounging for a
used one as RCA didn't put the actual part number on the parts because
they were subject to upgrades with new part numbers. The old program
also agrees that 244229 is the correct PART number, and it's NLA.
Various subs work, but sometimes have issues with geometry or ABL or
pix tearing problems. I've never used an H.R. in this chassis, but if
their sub is typical of other H.R.s I've used, I wouldn't be afraid of
it.

John

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

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

Electronics

sci.electronics.repair - 25 new messages in 8 topics - digest

No Response to "sci.electronics.repair - 25 new messages in 8 topics - digest"

Post a Comment

Blog Roll

Blog Archive