sci.electronics.repair@googlegroups.com

Today's topics:

* Cisco 3750G switch, fans not working - 5 messages, 5 authors
http://groups.google.com/group/sci.electronics.repair/t/5bd485fabbda76a0?hl=en
* Today's lead free story, and a "Mr Cook" moment ... - 10 messages, 6 authors
http://groups.google.com/group/sci.electronics.repair/t/8924a25c81bfe18e?hl=en
* Microwave Oven: Noisy, shuts down sometimes? - 5 messages, 3 authors
http://groups.google.com/group/sci.electronics.repair/t/8dc6fa75132215e7?hl=en
* RCA P60928 PTK195 Chassis no power - 3 messages, 3 authors
http://groups.google.com/group/sci.electronics.repair/t/0e7ca98063672b91?hl=en
* help needed with nikko 230 distortion - 2 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/e502374142af0b1b?hl=en

==============================================================================
TOPIC: Cisco 3750G switch, fans not working
http://groups.google.com/group/sci.electronics.repair/t/5bd485fabbda76a0?hl=en
==============================================================================

== 1 of 5 ==
Date: Fri, Oct 1 2010 12:50 am
From: "bob@bfisk.demon.co.uk"

Hi,
I have one of these on my workbench and both the fans aren't working,
the switch itself is fine. On inspection it appears that an SMD
component has come off the motherboard, Z1. Whether this was due to
bad soldering or if it's been knocked I can't tell. There doesn't
appear to be any signs of physical damage or heat.
Tracing the circuit shows that the power to the fans was delivered by
this component and I would suspect it was a zener. Without the
original I wouldn't have a clue what the value was and these days it's
highly unlikely to be marked anyway!
I'm unable to find any servicing info on these boxes so in desperation
I'm hoping somone might have one they could look inside. The only
other 3750's we have are single fan units and the power arrangement is
different.
I've also left a note on the Cisco site but so far not received any
replies.

Thanks
Bob

== 2 of 5 ==
Date: Fri, Oct 1 2010 5:14 am
From: Meat Plow

On Fri, 01 Oct 2010 00:50:17 -0700, bob@bfisk.demon.co.uk wrote:

> Hi,
> I have one of these on my workbench and both the fans aren't working,
> the switch itself is fine. On inspection it appears that an SMD
> component has come off the motherboard, Z1. Whether this was due to bad
> soldering or if it's been knocked I can't tell. There doesn't appear to
> be any signs of physical damage or heat. Tracing the circuit shows that
> the power to the fans was delivered by this component and I would
> suspect it was a zener. Without the original I wouldn't have a clue what
> the value was and these days it's highly unlikely to be marked anyway!
> I'm unable to find any servicing info on these boxes so in desperation
> I'm hoping somone might have one they could look inside. The only other
> 3750's we have are single fan units and the power arrangement is
> different.
> I've also left a note on the Cisco site but so far not received any
> replies.
>
> Thanks
> Bob

If all else fails look for another power source. The fans should be
marked per what they require. Probably 12 volts # .3 amps? Even an
external wall supply wired into the switch to provide fan voltage isn't
too bad an idea.

--
Live Fast, Die Young and Leave a Pretty Corpse

== 3 of 5 ==
Date: Fri, Oct 1 2010 5:25 am
From: PeterD

On Fri, 1 Oct 2010 00:50:17 -0700 (PDT), "bob@bfisk.demon.co.uk"
<bob@bfisk.demon.co.uk> wrote:

>Hi,
>I have one of these on my workbench and both the fans aren't working,
>the switch itself is fine. On inspection it appears that an SMD
>component has come off the motherboard, Z1. Whether this was due to
>bad soldering or if it's been knocked I can't tell. There doesn't
>appear to be any signs of physical damage or heat.
>Tracing the circuit shows that the power to the fans was delivered by
>this component and I would suspect it was a zener. Without the
>original I wouldn't have a clue what the value was and these days it's
>highly unlikely to be marked anyway!
>I'm unable to find any servicing info on these boxes so in desperation
>I'm hoping somone might have one they could look inside. The only
>other 3750's we have are single fan units and the power arrangement is
>different.
>I've also left a note on the Cisco site but so far not received any
>replies.
>
>Thanks
>Bob

How many volts are the fans? How many volts does the power supply
deliver? Same? Connect fans directly to powersupply... Different:
adaptive circuit to change voltage (regulator for example).

My bet is that they are the same...

== 4 of 5 ==
Date: Fri, Oct 1 2010 11:35 am
From: nesesu

On Oct 1, 12:50 am, "b...@bfisk.demon.co.uk" <b...@bfisk.demon.co.uk>
wrote:
> Hi,
> I have one of these on my workbench and both the fans aren't working,
> the switch itself is fine. On inspection it appears that an SMD
> component has come off the motherboard, Z1. Whether this was due to
> bad soldering or if it's been knocked I can't tell. There doesn't
> appear to be any signs of physical damage or heat.
> Tracing the circuit shows that the power to the fans was delivered by
> this component and I would suspect it was a zener. Without the
> original I wouldn't have a clue what the value was and these days it's
> highly unlikely to be marked anyway!
> I'm unable to find any servicing info on these boxes so in desperation
> I'm hoping somone might have one they could look inside. The only
> other 3750's we have are single fan units and the power arrangement is
> different.
> I've also left a note on the Cisco site but so far not received any
> replies.
>
> Thanks
> Bob

Consider the possibility that the missing components was a chip fuse
or a fuse resistor. If one fan faulted, a fuse resistor could heat
enough to melt the solder, but it is unlikely it would drop off the
board until the solder lost all it's surface tension properties.
Likewise with a Zener. Has someone been in there before you? If not
the part may still ba floating around or stuck onto the board nearby.
I agree with others that the supply voltage and fan voltages are
likely the same.

Neil S.

== 5 of 5 ==
Date: Fri, Oct 1 2010 3:16 pm
From: whit3rd

On Oct 1, 12:50 am, "b...@bfisk.demon.co.uk" <b...@bfisk.demon.co.uk>
wrote:

> I have one of these on my workbench and both the fans aren't working,
> the switch itself is fine. On inspection it appears that an SMD
> component has come off the motherboard, Z1. Whether this was due to
> bad soldering or if it's been knocked I can't tell. There doesn't
> appear to be any signs of physical damage or heat.
> Tracing the circuit shows that the power to the fans was delivered by
> this component and I would suspect it was a zener.

If it's in series with the fans, and they're 12V fans, you can reverse-
engineer
the component value. Usually, there WOULD NOT be a Zener in series,
because Zeners fail (typically) in short circuit; it'd more likely
be a limit resistor, or maybe even a thermal-sensing resistor with a
negative temperature coefficient.

I'd expect "ZD" or "CR" markings for a Zener diode.

I'd also expect the component to be rattling around inside the case
somewhere (get a hand lens and do the Sherlock thing...).

==============================================================================
TOPIC: Today's lead free story, and a "Mr Cook" moment ...
http://groups.google.com/group/sci.electronics.repair/t/8924a25c81bfe18e?hl=en
==============================================================================

== 1 of 10 ==
Date: Fri, Oct 1 2010 5:10 am
From: Meat Plow

On Fri, 01 Oct 2010 02:35:35 +0100, Arfa Daily wrote:

> "Meat Plow" <mhywatt@yahoo.com> wrote in message
> news:pan.2010.09.30.11.23.04@lmao.lol.lol...
>> On Thu, 30 Sep 2010 02:29:22 +0100, Arfa Daily wrote:
>>
>>> Fender combo. Owner complained that sound level varied, or sound went
>>> off altogether for brief periods, after a half hour of use. Additional
>>> symptom was that the status LEDs on the footpedal flickered. He said
>>> that he'd looked it up on the net, and many people had reported that
>>> this problem was caused by the two ceramic feed resistors in the low
>>> voltage + and - rails, having bad joints. OK, we've all seen this, I
>>> guess. Anyways, unit would not fault on my bench, and no amount of
>>> pushing, prodding, poking, bashing, heating or freezing, would provoke
>>> it, so reluctantly, I had to remove the main board to get a look
>>> behind it. I say reluctantly, because it's a bit of a long winded job
>>> involving removal of all of the (grub screwed) knobs, pot nuts and
>>> washers, jack nuts and washers etc. When the board was out, I had a
>>> really detailed look at all the joints with a powerful light and my
>>> headband magnifier, but no joints actually looked bad anywhere,
>>> including on the two ceramic resistors. So I went for the Mr Cook test
>>> and grabbed the wires on those resistors one by one with pliers, and
>>> pulled. And Lo! On the third one, it pulled cleanly and easily from
>>> the joint, leaving the now dreaded 'volcano' behind. How much longer
>>> are we going to have to put up with this crap ? It's not as if it's
>>> the quick 'good little earner' that bad joints used to be when you
>>> could find them in a minute or two with a Biro pen, a can of freezer,
>>> and a Mk I eyeball ...
>>>
>>> Arfa
>>
>> I know you have but I will say this anyway. Compared to pulling a
>> certain Mackie 16 ch mixer apart where all sixteen channels are on one
>> board, and where I counted 102 mini shaft nuts removed with needle nose
>> because I didn't have a shaft nut driver that small, and an additional
>> 48 philips screws just to replace one LED, your experience with the
>> Fender is a walk in the park on a sunny day.
>>
>>
>>
> Oh I know, Meat, I know ... Not so long back, I did a similar one with
> over 100 knobs. I had to take a picture of it to make sure they all went
> back where they should. Just putting the knobs back on took about a half
> hour, let alone all the nuts and washers ... !!
>
> Arfa

OooOOOOooOOOooo my head aches! You reminded me of the 204 washers (102
under the shaft nuts and 102 on top of each pot under the board top) and
102 knobs on splined split pot shafts that WOULD NOT pull off by
hand!!! :) Each had to be pried off with a flat screwdriver and small
block of wood for a fulcrum. And all the knobs in each channel were
different colors denoting the particular function (mains, buss, FX,
etc...) making it a real pain in the ass because rather than just laying
one channel out to remember the knob order I laid them all out so I
wouldn't have to fish through a box of hundred different color knobs.

Next to the Kurzweil piano and its 88, 3 part mini leaf switches, that
board was probably the most PITA thing I've ever worked on.

--
Live Fast, Die Young and Leave a Pretty Corpse

== 2 of 10 ==
Date: Fri, Oct 1 2010 7:01 am
From: George Herold

On Sep 30, 11:22 am, "Michael A. Terrell" <mike.terr...@earthlink.net>
wrote:
> Arfa Daily wrote:
>
> > Fender combo. Owner complained that sound level varied, or sound went off
> > altogether for brief periods, after a half hour of use. Additional symptom
> > was that the status LEDs on the footpedal flickered. He said that he'd
> > looked it up on the net, and many people had reported that this problem was
> > caused by the two ceramic feed resistors in the low voltage + and - rails,
> > having bad joints. OK, we've all seen this, I guess. Anyways, unit would not
> > fault on my bench, and no amount of pushing, prodding, poking, bashing,
> > heating or freezing, would provoke it, so reluctantly, I had to remove the
> > main board to get a look behind it. I say reluctantly, because it's a bit of
> > a long winded job involving removal of all of the (grub screwed) knobs, pot
> > nuts and washers, jack nuts and washers etc. When the board was out, I had a
> > really detailed look at all the joints with a powerful light and my headband
> > magnifier, but no joints actually looked bad anywhere, including on the two
> > ceramic resistors. So I went for the Mr Cook test and grabbed the wires on
> > those resistors one by one with pliers, and pulled. And Lo! On the third
> > one, it pulled cleanly and easily from the joint, leaving the now dreaded
> > 'volcano' behind. How much longer are we going to have to put up with this
> > crap ? It's not as if it's the quick 'good little earner' that bad joints
> > used to be when you could find them in a minute or two with a Biro pen, a
> > can of freezer, and a Mk I eyeball ...
>
>    Its time for a full blown ROHS revolt.  String the morons up on light
> poles as a warning to other idiot Beauracrats. :)
>
> --
> Politicians should only get paid if the budget is balanced, and there is
> enough left over to pay them.- Hide quoted text -
>
> - Show quoted text -

My wife bought another kitchen appliance (hand blender) the other
day. Attached to the power cord was a warning... which I will
paraphrase. "Warning this power cord contains lead. Lead is known to
the State of California to cause cancer and birth defects. Wash your
hands after using." My nine year old son dutifully washed his hands.
(He wanted to play with the new gadget.) I had a mini-rant in the
kitchen.

This is wrong in so many ways it just boggles the mind.

George H.

== 3 of 10 ==
Date: Fri, Oct 1 2010 7:07 am
From: "Michael A. Terrell"

George Herold wrote:
>
> My wife bought another kitchen appliance (hand blender) the other
> day. Attached to the power cord was a warning... which I will
> paraphrase. "Warning this power cord contains lead. Lead is known to
> the State of California to cause cancer and birth defects. Wash your
> hands after using." My nine year old son dutifully washed his hands.
> (He wanted to play with the new gadget.) I had a mini-rant in the
> kitchen.
>
> This is wrong in so many ways it just boggles the mind.

There are traces of lead in some plastics used to make wire. I think
it is part of the plasticiser needed to make the insulation flexible.

California isn't know as the land of fruits & nuts for nothing. :(

--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.

== 4 of 10 ==
Date: Fri, Oct 1 2010 10:01 am
From: "Herman"

"Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message
news:qKSdnVlWw96CdjjRnZ2dnUVZ_g-dnZ2d@earthlink.com...
>
> George Herold wrote:
>>
>> My wife bought another kitchen appliance (hand blender) the other
>> day. Attached to the power cord was a warning... which I will
>> paraphrase. "Warning this power cord contains lead. Lead is known to
>> the State of California to cause cancer and birth defects. Wash your
>> hands after using." My nine year old son dutifully washed his hands.
>> (He wanted to play with the new gadget.) I had a mini-rant in the
>> kitchen.
>>
>> This is wrong in so many ways it just boggles the mind.
>
>
> There are traces of lead in some plastics used to make wire. I think
> it is part of the plasticiser needed to make the insulation flexible.
>
> California isn't know as the land of fruits & nuts for nothing. :(
>
>
> --
> Politicians should only get paid if the budget is balanced, and there is
> enough left over to pay them.

I live in New Orleans. Every day 4 or 5 people die due to lead. Bullets.

== 5 of 10 ==
Date: Fri, Oct 1 2010 10:32 am
From: PlainBill47@yawho.com

On 1 Oct 2010 01:59:39 GMT, Spamm Trappe
<knock_yourself_out@example.net> wrote:

>On Thu, 30 Sep 2010 10:37:22 -0700, PlainBill47@yawho.com wrote:
>>
>> The fact is that lead in the food chain IS a problem. Banning lead
>> in paints (in particular paints used in children't toys), in the
>> paints and glazes used on ceramic containers, etc is a very good idea.
>
>I'm not so sure. Ever since 'they' removed lead from toys, house paint,
>gasoline, candle wicks, now solder, and gawd knows what else, we ("we":
>the U.S.) have had year after year of dumber and dumber children.
>
I take it you are offering yourself as an example.
>
>Don't get me started about how out of whack global weather has become
>since 'they' banned atmospheric testing of thermonuclear weapons...
Well, if you plot climate changes against atmospheric testing of
thermonuclear weapons you don't get a very good match. Hoever, if
you plot climate changes against CO2 levels you get a pretty good
match.

Of course, both curves also match well to concentration of modulated
radio waves in the electromagnetic spectrum; and to number of internal
combustion engines.

PlainBill

== 6 of 10 ==
Date: Fri, Oct 1 2010 10:34 am
From: PlainBill47@yawho.com

On Fri, 1 Oct 2010 12:01:15 -0500, "Herman" <ripe@bellsouth.net>
wrote:

>
>"Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message
>news:qKSdnVlWw96CdjjRnZ2dnUVZ_g-dnZ2d@earthlink.com...
>>
>> George Herold wrote:
>>>
>>> My wife bought another kitchen appliance (hand blender) the other
>>> day. Attached to the power cord was a warning... which I will
>>> paraphrase. "Warning this power cord contains lead. Lead is known to
>>> the State of California to cause cancer and birth defects. Wash your
>>> hands after using." My nine year old son dutifully washed his hands.
>>> (He wanted to play with the new gadget.) I had a mini-rant in the
>>> kitchen.
>>>
>>> This is wrong in so many ways it just boggles the mind.
>>
>>
>> There are traces of lead in some plastics used to make wire. I think
>> it is part of the plasticiser needed to make the insulation flexible.
>>
>> California isn't know as the land of fruits & nuts for nothing. :(
>>
>>
>> --
>> Politicians should only get paid if the budget is balanced, and there is
>> enough left over to pay them.
>
>I live in New Orleans. Every day 4 or 5 people die due to lead. Bullets.
>
Point that out to the NRA. They will retaliater with reams of data
'proving' that handguns save lives.

PlainBill

== 7 of 10 ==
Date: Fri, Oct 1 2010 10:42 am
From: "Michael A. Terrell"

Herman wrote:
>
> I live in New Orleans. Every day 4 or 5 people die due to lead. Bullets.

More proof that New Orleans should be backfilled.

--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.

== 8 of 10 ==
Date: Fri, Oct 1 2010 10:43 am
From: "Michael A. Terrell"

PlainBill47@yawho.com wrote:
>
> On Fri, 1 Oct 2010 12:01:15 -0500, "Herman" <ripe@bellsouth.net>
> wrote:
>
> >
> >"Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message
> >news:qKSdnVlWw96CdjjRnZ2dnUVZ_g-dnZ2d@earthlink.com...
> >>
> >> George Herold wrote:
> >>>
> >>> My wife bought another kitchen appliance (hand blender) the other
> >>> day. Attached to the power cord was a warning... which I will
> >>> paraphrase. "Warning this power cord contains lead. Lead is known to
> >>> the State of California to cause cancer and birth defects. Wash your
> >>> hands after using." My nine year old son dutifully washed his hands.
> >>> (He wanted to play with the new gadget.) I had a mini-rant in the
> >>> kitchen.
> >>>
> >>> This is wrong in so many ways it just boggles the mind.
> >>
> >>
> >> There are traces of lead in some plastics used to make wire. I think
> >> it is part of the plasticiser needed to make the insulation flexible.
> >>
> >> California isn't know as the land of fruits & nuts for nothing. :(
> >>
> >>
> >> --
> >> Politicians should only get paid if the budget is balanced, and there is
> >> enough left over to pay them.
> >
> >I live in New Orleans. Every day 4 or 5 people die due to lead. Bullets.
> >
> Point that out to the NRA. They will retaliater with reams of data
> 'proving' that handguns save lives.

They do, but you only see what you want to.

--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.

== 9 of 10 ==
Date: Fri, Oct 1 2010 11:07 am
From: "William Sommerwerck"

> There are traces of lead in some plastics used to make wire.
> I think it is part of the plasticiser needed to make the insulation
> flexible.

Right. The cord on the tuner/remote for my Sony Discman has such a warning.

I'm all in favor in "getting the lead out", especially in products that kids
come in contact with. Ideally, warnings should be based on the likely
exposure, not the mere presence of lead (or anything else). In practice,
it's easier simply to condemn everything.

Considering that the blender's cord would rarely be touched (and then only
at the plug end), there doesn't seem much point.

> California isn't know as the land of fruits & nuts for nothing. :(

Watch it...

== 10 of 10 ==
Date: Fri, Oct 1 2010 4:10 pm
From: "Michael A. Terrell"

William Sommerwerck wrote:
>
> > There are traces of lead in some plastics used to make wire.
> > I think it is part of the plasticiser needed to make the insulation
> > flexible.
>
> Right. The cord on the tuner/remote for my Sony Discman has such a warning.
>
> I'm all in favor in "getting the lead out", especially in products that kids
> come in contact with. Ideally, warnings should be based on the likely
> exposure, not the mere presence of lead (or anything else). In practice,
> it's easier simply to condemn everything.
>
> Considering that the blender's cord would rarely be touched (and then only
> at the plug end), there doesn't seem much point.
>
> > California isn't know as the land of fruits & nuts for nothing. :(
>
> Watch it...

I was talking about their politicians. :)

--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.

==============================================================================
TOPIC: Microwave Oven: Noisy, shuts down sometimes?
http://groups.google.com/group/sci.electronics.repair/t/8dc6fa75132215e7?hl=en
==============================================================================

== 1 of 5 ==
Date: Fri, Oct 1 2010 5:54 am
From: "N_Cook"

(PeteCresswell) <x@y.Invalid> wrote in message
news:l8o7a6pscmebkgl0feooiq4j62rlt7egtm@4ax.com...
> Fairly new oven - but out of warranty.
>
> Makes a lot of noise when running.
>
> Aside from the noise, it works OK... mostly.
>
> But every so often, when heating something for more than about 3
> minutes, it just shuts off. Totally: no LED readout, no nothing.
>
> Then, maybe 10 minutes later, it comes back to life.
>
> Maybe some kind of safety breaker getting tripped by heat and
> coming back on when things cool down?
>
> I'm wondering if it's worth buying the special tamper-resistant
> Torx driver and tearing the thing down - or better to just spring
> for the $200 or so to buy a new one.
> --
> PeteCresswell

One source of noise can be the windings of the transformer rattling against
one another due to the serious currents

== 2 of 5 ==
Date: Fri, Oct 1 2010 6:08 am
From: "William Sommerwerck"

> One source of noise can be the windings of the transformer
> rattling against one another due to the serious currents.

Would the amperage drawn by the lamp in the oven be considered a "lighter"
current?

== 3 of 5 ==
Date: Fri, Oct 1 2010 8:06 am
From: "N_Cook"

William Sommerwerck <grizzledgeezer@comcast.net> wrote in message
news:i84mjj$30d$1@news.eternal-september.org...
> > One source of noise can be the windings of the transformer
> > rattling against one another due to the serious currents.
>
> Would the amperage drawn by the lamp in the oven be considered a "lighter"
> current?
>
>

Anything is possible. A supermarket near me has free-range sausages for sale

== 4 of 5 ==
Date: Fri, Oct 1 2010 11:03 am
From: "William Sommerwerck"

>>> One source of noise can be the windings of the transformer
>>> rattling against one another due to the serious currents.

>> Would the amperage drawn by the lamp in the oven be
>> considered a "lighter" current?

> Anything is possible. A supermarket near me has free-range
> sausages for sale.

I can just see the pork-boys roundin' 'em up...

== 5 of 5 ==
Date: Fri, Oct 1 2010 2:57 pm
From: Puddin' Man

On Wed, 29 Sep 2010 21:03:10 -0400, "(PeteCresswell)" <x@y.Invalid> wrote:

>Fairly new oven - but out of warranty.
>
>Makes a lot of noise when running.
>
>Aside from the noise, it works OK... mostly.
>
>But every so often, when heating something for more than about 3
>minutes, it just shuts off. Totally: no LED readout, no nothing.
>
>Then, maybe 10 minutes later, it comes back to life.
>
>Maybe some kind of safety breaker getting tripped by heat and
>coming back on when things cool down?
>
>I'm wondering if it's worth buying the special tamper-resistant
>Torx driver and tearing the thing down - or better to just spring
>for the $200 or so to buy a new one.

You can get a kit of specialty fastener bits at Harbor Freight
or ? for $5-6, last I looked. Should handle 95+% of what you'll
run into.

Aside from that, if you're a tinker, you'll take a look-see.
If not, ya buy a new one.

P

"Law Without Equity Is No Law At All. It Is A Form Of Jungle Rule."

==============================================================================
TOPIC: RCA P60928 PTK195 Chassis no power
http://groups.google.com/group/sci.electronics.repair/t/0e7ca98063672b91?hl=en
==============================================================================

== 1 of 3 ==
Date: Fri, Oct 1 2010 7:55 am
From: "Tmachcinsk@aol.com"

I had a power surge that killed my TV and microwave. PTK 195 chassis.
I get no picture no sound no attempt to power on. No clicking.
Nothing. Main fuse is ok power is ok just past the fuse. Any ideas.
Thanks Ted

== 2 of 3 ==
Date: Fri, Oct 1 2010 10:44 am
From: PlainBill47@yawho.com

On Fri, 1 Oct 2010 07:55:40 -0700 (PDT), "Tmachcinsk@aol.com"
<Tmachcinsk@aol.com> wrote:

>I had a power surge that killed my TV and microwave. PTK 195 chassis.
>I get no picture no sound no attempt to power on. No clicking.
>Nothing. Main fuse is ok power is ok just past the fuse. Any ideas.
>Thanks Ted
Several.
1. I was not aware anyone had sold a combination TV and microwave.
2. Giving the chassis number properly assists in searching. (it is the
PTK195 chassis, not the PTK 195).
3. The Photofact album is available at http://elektrotanya.com

PlainBill

== 3 of 3 ==
Date: Fri, Oct 1 2010 5:12 pm
From: John-Del

On Oct 1, 10:55 am, "Tmachci...@aol.com" <Tmachci...@aol.com> wrote:
> I had a power surge that killed my TV and microwave. PTK 195 chassis.
> I get no picture no sound no attempt to power on. No clicking.
> Nothing. Main fuse is ok power is ok just past the fuse. Any ideas.
> Thanks Ted

The 195 is not a modular chassis, it is expected that anyone who
attempts repair can troubleshoot to the component level, and deal with
surface mounted devices. That said, the 195 is extraordinarily
reliable, earlier versions needing a flyback perhaps, but a long lived
and excellent performing analog TV.

Start by checking for 5 volts at the IR receiver on top of the light
box. If that's there, you have a system control problem, maybe the
micro reset circuit, corrupted eeprom, etc. If no 5v exists, the main
smps is out. Watch out, this supply holds a vicious charge for a long
time.

==============================================================================
TOPIC: help needed with nikko 230 distortion
http://groups.google.com/group/sci.electronics.repair/t/e502374142af0b1b?hl=en
==============================================================================

== 1 of 2 ==
Date: Fri, Oct 1 2010 5:16 pm
From: james moffat

HI all!
I have a nikko alpha 230 amp that is distorting one channel <just
enough to annoy my ears>
and was wondering if anyone has any advise on what to check for / and
or replace to get rid of the noise.
If it makes any difference to the diagnosis the music is fine at the
headphones, and is only distorted on the left channel.
I have enough knowledge to make me dangerous, and some test
equipment<no o-scope>
so if someone is willing to help me learn a little more please blast
away.
thanks for your time
remove the spam to e-mail me.
james
If you really want to talk to me - just eat the spam

== 2 of 2 ==
Date: Fri, Oct 1 2010 6:01 pm
From: "Arfa Daily"

"james moffat" <kallispamta@shaw.ca> wrote in message
news:f3uca61pr4k5h2nbrl2mn0bec2vbv7v32v@4ax.com...
>
> HI all!
> I have a nikko alpha 230 amp that is distorting one channel <just
> enough to annoy my ears>
> and was wondering if anyone has any advise on what to check for / and
> or replace to get rid of the noise.
> If it makes any difference to the diagnosis the music is fine at the
> headphones, and is only distorted on the left channel.
> I have enough knowledge to make me dangerous, and some test
> equipment<no o-scope>
> so if someone is willing to help me learn a little more please blast
> away.
> thanks for your time
> remove the spam to e-mail me.
> james
> If you really want to talk to me - just eat the spam

I suppose that you've done the obvious, and swapped the speakers between
channels ?

Arfa

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