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

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

sci.electronics.repair@googlegroups.com

Today's topics:

==============================================================================
TOPIC: 40Gb Western Digital hard drive
http://groups.google.com/group/sci.electronics.repair/t/d11c27dd9c7d80c0?hl=en
==============================================================================

== 1 of 8 ==
Date: Thurs, Jun 3 2010 10:24 am
From: Meat Plow

On Thu, 03 Jun 2010 10:04:06 -0700, mike ǝʇoɹʍ:

> AZ Nomad wrote:
>
>> Only thing with scsi is you have to address each drive, and have
>> termination at the end of the cable.
>> I ran scsi between 1995 and 2001.
>>
>> The various flavors of scsi (scsi-1, scsi-2, wide, ultrawide, fast,
>> etc.) may make matching controller to drive interesting if they're not
>> already matched. There's at least three different connectors I know of
>> plus varients that are differential or hotswappable.
>
> Hmm, scsi stuff must still be somewhat valuable no matter what the age,
> judging from the fact that I almost never find any at the local
> scrapyard - so far I've got one cable, one controller card and one
> drive, and I've been frequenting the scrapyard since about 1985. Well, I
> guess there could be some other reason for it, but that's what I
> conclude, at least so far...anyway, thanks for the info.
>
> Mike

My scrap bin has lots of SCSI stuff. Cables both internal and external,
some Seagate 4.3 gig 7200 RPM drives, one is new. A couple Adaptec PCI
cards, terminators, a Plextor SCSI CDRW, external SCSI drive enclosure I
made from an IBM SCSI drive inside the case of a former HP external tape
drive. My very first CDR was a 1x HP SCSI internal back when 1x was the
fastest. CD recording was pretty flaky back then. Hold your breath and
cross your fingers flaky.

== 2 of 8 ==
Date: Thurs, Jun 3 2010 2:34 pm
From: "Michael A. Terrell"

Michael Kennedy wrote:
>
> "Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message
> news:mpmdnfg0GbaWHZrRnZ2dnUVZ_rKdnZ2d@earthlink.com...
> >
> > Michael Kennedy wrote:
> >>
> >> "Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message
> >> news:6b2dncCN0OpBjJrRnZ2dnUVZ_vednZ2d@earthlink.com...
> >> >
> >> > mike wrote:
> >> >>
> >> >> Michael A. Terrell wrote:
> >> >>
> >> >> > Doesn't it have at least one empty slot where you can install a
> >> >> > better video card? You can use multiple drives without installing a
> >> >> > RAID driver. Don't pitch it out, if it works.
> >> >>
> >> >> Oh, no, I'd never pitch anything out, (unless maybe I tripped over it
> >> >> and broke a toe or somethin')
> >> >>
> >> >> >Play with it. Install a
> >> >> > version of Linux or use it for a test bed computer. You can remove
> >> >> > the
> >> >> > rack mount brackets on a lot of server cases and use them as a big
> >> >> > desktop computer, or you can use some scrap lumber an made a crude
> >> >> > rack
> >> >> > for it.
> >> >>
> >> >> I guess that the main obstacle is I don't know anything about scsi;
> >> >> there are no drives in the drive bay, and there's a scsi bus but I
> >> >> don't know jack about scsi. I've got a 2.1 Gb scsi drive, and some
> >> >> kind of scsi controller card, but just haven't spent much time looking
> >> >> into it yet.
> >> >>
> >> >> Thanks,
> >> >> Mike
> >> >
> >> >
> >> > Then stick an IDE or SATA controller card in there. They don't have
> >> > to run SCSI drives. You may have to change some settings in the BIOS,
> >> > but that isn't difficult.
> >>
> >> Or Just throw a scsi drive in there and play around with it. They're not
> >> that complicated. Don't run away from something just because you don't
> >> know
> >> how it works. Use it as an opportunity to broden your knowledge.
> >
> >
> > He didn't say what type of SCSI drive he needed. He may be missing
> > the trays to hold a SCSI drive, as well. I was just offering a way to
> > get it running, if everything else was good. The used Dell Power Edge
> > 4350 I picked up for free last week works, and had three 36 G hard
> > drives and a gig of RAM. The OS had been wiped, but I plan on using it
> > as an Apache and Leafnode server. I installed Win 2000 to test the
> > hardware, but I won't be using that OS.
> >
> >
>
> Good point. I forgot that servers have those trays to hold the hdd's..
> I've been out of the PC game going on 2 years now. I really miss working on
> anything. Time for a job change. My passion is building and repairing
> things. When I finally get back to Florida maybe I can.

If you come back to the same area let me know. We might run into
each other some day. Like the Orlando hamfest. :)

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

== 3 of 8 ==
Date: Thurs, Jun 3 2010 2:37 pm
From: "Michael A. Terrell"

mike wrote:
>
> Michael A. Terrell wrote:
>
> > He didn't say what type of SCSI drive he needed. He may be missing
> > the trays to hold a SCSI drive, as well. I was just offering a way to
> > get it running, if everything else was good. The used Dell Power Edge
> > 4350 I picked up for free last week works, and had three 36 G hard
> > drives and a gig of RAM. The OS had been wiped, but I plan on using it
> > as an Apache and Leafnode server. I installed Win 2000 to test the
> > hardware, but I won't be using that OS.
>
> You scored big time for sure. The Proliant came with 512 Mb, and
> trays that say '36.4 Gb 10K Ultra Scsi'. Unfortunately all the trays
> are empty :(
> The connector that the drives plug into are wider than the one on the
> scsi drive I've got.

If they are 80 pin, here are some cheap 9 GB drives:

http://www.geeks.com/details.asp?invtid=IC35L009UCD210-R&cat=HDD

for $5.99 + shipping.

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

== 4 of 8 ==
Date: Thurs, Jun 3 2010 2:40 pm
From: "Michael A. Terrell"

mike wrote:
>
> Michael A. Terrell wrote:
> > mike wrote:
> > >
> > > Michael A. Terrell wrote:
> > >
>
> >
> >
> > Then stick an IDE or SATA controller card in there. They don't have
> > to run SCSI drives. You may have to change some settings in the BIOS,
> > but that isn't difficult.
>
> Excellent idea, guess I was suffering from some mental blockage; it
> would just take some creative cable routing to get to the drive bays.
> I was just looking at it and now recall that I'd figured the memory in
> it justified the cost of it even if it didn't run, but it does start
> up and I've looked around in the bios a little bit. However, it only
> has one processor installed, which is a PIII-S SL5PU. Kind a doubt
> that it's available any more, guess I'll have to check the docs and
> see what kind of processors will work in it.

Look for them on Ebay, or places like geeks.com or pacificgeek.com

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

== 5 of 8 ==
Date: Thurs, Jun 3 2010 6:12 pm
From: mike

On Jun 3, 5:34 pm, "Michael A. Terrell" <mike.terr...@earthlink.net>
wrote:

>
> If you come back to the same area let me know. We might run into
> each other some day. Like the Orlando hamfest. :)
>
what are you talkin' about, I'm always here, can't afford to go
anywhere...

http://buncombe.main.nc.us/~mikel/index2.html

== 6 of 8 ==
Date: Thurs, Jun 3 2010 6:15 pm
From: mike

On Jun 3, 5:37 pm, "Michael A. Terrell" <mike.terr...@earthlink.net>
wrote:

> If they are 80 pin, here are some cheap 9 GB drives:
>
> http://www.geeks.com/details.asp?invtid=IC35L009UCD210-R&cat=HDD
>
> for $5.99 + shipping.
That sounds pretty good, thanks.

== 7 of 8 ==
Date: Thurs, Jun 3 2010 6:38 pm
From: mike

On Jun 2, 8:43 pm, Jeff Liebermann <je...@cruzio.com> wrote:

> We'll, I wouldn't mind, but there's a problem. I don't keep any
> obviously defective drives and only save the paperwork on the good
> drives. The ones in between are kinda arbitrary. I'll keep results
> on the newer and better drives, but not on the older marginal junk.
> It's really not that much of a time burner. I have several test
> machines and boards, and usually let them run overnight.

Hmm, I guess I need to get a little bit better organized...

> My rule-of-thumb is that if the diagnostic says it's bad, it's almost
> certainly bad. If the diagnostic says it's good, it might be, but
> might also be bad due to some reason that wasn't obvious or tested. I
> once tested a drive (with a different program) that had obvious
> bearing spin (very noisy), but tested good.

I've got a couple noisy (smaller capacity) ones, it's tempting to keep
using them, just to see how
long they last.
>
> >On a slightly different subject, when I got curious about the
> >definition of 'low-level format', I did some googling on the subject
> >and checked out the Wikipedia for a bit and now I don't know whether I
> >even did any low-level formatting in the last few days, though I do
> >know that I used to in the early 80's - oh, well I guess that's
> >"progress' for ya.
>
> Low level format is usually done by the factory, and never again. It's
> places the sector numbers and servo tracks on the platter. There are
> programs that plug into the diagnstic port of the drive that will
> recreate the sector numbers, bios preload area, diagnostic tracks, and
> landing zone allocation, but not the servo tracks. If the drive seems
> to require a new primary format, give up now.
>
> Hint: I have a 15 year old Conner CP1060S 1GB drive sitting in my SCO
> Unix 3.2v4.2 server.

haven't seen the name 'Conner' for quite awhile now, I'd forgotten
about them...

It's been running continuously since about
> 1995(?). Three mother boards (486DX2/66), one video card, and one
> Wangtek tape controller card have blown up during this time. The
> secret to long HD life is leave it running all the time and protect it
> from power and static electricity glitches. I have other servers that
> have done almost as well, but this one is my oldest.

That's pretty amazing, for sure!

== 8 of 8 ==
Date: Thurs, Jun 3 2010 8:21 pm
From: "Michael A. Terrell"

mike wrote:
>
> On Jun 3, 5:34 pm, "Michael A. Terrell" <mike.terr...@earthlink.net>
> wrote:
>
> >
> > If you come back to the same area let me know. We might run into
> > each other some day. Like the Orlando hamfest. :)
> >
> what are you talkin' about, I'm always here, can't afford to go
> anywhere...
>
> http://buncombe.main.nc.us/~mikel/index2.html

That reply was to Michael Kennedy. He used to live abut 45 minutes
from me. He was between me and Orlando. I am in a little better health
these days, and am almost ready to try the long drive to Orlando. After
I get the A/C in the truck fixed. :(

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

==============================================================================
TOPIC: 15-25VDC 110-250VAC Adaptors
http://groups.google.com/group/sci.electronics.repair/t/8d76686c3dea3474?hl=en
==============================================================================

== 1 of 2 ==
Date: Thurs, Jun 3 2010 10:40 am
From: vjp2.at@at.BioStrategist.dot.dot.com

How reliable are such adaptors sold as "universal laptop adaptor"?

- = -
Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist
http://www.panix.com/~vjp2/vasos.htm
---{Nothing herein constitutes advice. Everything fully disclaimed.}---
[Homeland Security means private firearms not lazy obstructive guards]
[Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]

== 2 of 2 ==
Date: Thurs, Jun 3 2010 12:20 pm
From: news@jecarter.us

On Thu, 3 Jun 2010 17:40:16 +0000 (UTC),
vjp2.at@at.BioStrategist.dot.dot.com wrote:

Depends on what brand you get. Targus has been making good equipment
for a long time. If you've never seen the brand anywhere else, you
probably shouldn't buy it...

John

>How reliable are such adaptors sold as "universal laptop adaptor"?
>
>
>
> - = -
> Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist
> http://www.panix.com/~vjp2/vasos.htm
> ---{Nothing herein constitutes advice. Everything fully disclaimed.}---
> [Homeland Security means private firearms not lazy obstructive guards]
> [Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]
>
>

==============================================================================
TOPIC: Surge Protectors
http://groups.google.com/group/sci.electronics.repair/t/9a42e9c9a84828d9?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Jun 3 2010 11:01 am
From: bud--

Cydrome Leader wrote:
> Michael A. Terrell <mike.terrell@earthlink.net> wrote:
>> vjp2.at@at.BioStrategist.dot.dot.com wrote:
>>> *+-even the cheap suppressors I've bought had 3 MOVs,one for each leg to
>>> *+-ground and from one leg to the other. I guess that's a "delta" config.
>>>
>>> Do surge supressors exist for two-line phone connections?
>>>
>>> WOuld it make sence to put a surge suppressor (what kind?) on my
>>> incoming phone line? Neighbors have complained of fried modems, but
>>> curiously I don't remember anyone ever telling mtheir computer got fried.
>>
>> There should already be one inside the phone company's Network
>> Interface.
>
> This applies to the US-
>
> there are surge and lightning arrestors on phone lines where they enter a residence, and they're
> grounded to something good, like a water pipe for instance.
>
> It works great.

Some comments are somewhat specific to the US.

A couple of excellent sources of info on surge protection are:
<http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf>
from the IEEE, and a much simpler one from the US-NIST
<http://www.nist.gov/public_affairs/practiceguides/surgesfnl.pdf>

With a strong surge current to the earthing electrode, the "ground" for
the building can rise thousands of volts above "absolute" earth
potential. You want power and phone (and cable) wires rise together.
That requires a short ground wire from the telephone entrance protector
to the earthing system at the power service.

>
> Now if lightning surges hit your power then what happens?
>
> a cheapo-garbage "surge protector" like a power strip or the like will use MOVs to short out line
> to neutral or even line to ground.
>
> What happens if you throw a short across line to ground and can somehow clamp it to 600 volts or
> whatever? The numbers are made up, but concept is the same.
>
> well, your ground ends up at 300 volts above actual earth ground where that device is located. This
> assumes your ground has the same impedance as the current carrying conductors.
>
> So now your computer isn't really grounded, and floating at a potential way off what the phone like
> is at, which worst case is being protected to a really solid ground, and not hundreds of feet or
> wiring in your walls or whatever.
>
> This is what blows up stuff like modems or devices that sit between your outlets and a phone line.

If you RTFM, any competent plug-in suppressor manufacturer should tell
you the phone wires have to go through the suppressor along with the
power wires. The voltage on all wires is clamped to the ground at the
suppressor. The voltage between the wires to the protected equipment is
safe for the protected equipment. All interconnected equipment needs to
be connected to the same suppressor, or external wires, like cable need
to go through the suppressor. This is clearly explained in the IEEE
guide starting pdf page 40, and shown in the examples at the end.
Plug-in suppressors work primarily by clamping, not earthing.

>
> The best move is to install a service entrance surge supressor. They'll clamp surges at the best
> ground you've got, with the lowest possible impedance, and at your ground/nuetral bonding point not
> at your load where any attempts to do so are pretty useless across the extra fraction of an ohm.

Service panel suppressors are a real good idea. I would particularly use
one in high risk areas like Florida.

But from the NIST guide:
"Q - Will a surge protector installed at the service entrance be
sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances
[electronic equipment], No for two-link appliances [equipment connected
to power AND phone or cable or....]. Since most homes today have some
kind of two-link appliances, the prudent answer to the question would be
NO - but that does not mean that a surge protector installed at the
service entrance is useless."

The NIST guide suggests most damage results from high voltage between
power and phone/cable wires. A service entrance suppressor does not, by
itself, limit that voltage.

>
> You can easily test the resistance of your wiring at home too, and at the same time actually test
> if your ground is solid.
>
> connect some large resistive loads like halogen lamps, hairdryer, toaster oven or whatever at and
> outlet. Measure the voltage drop when it's on. Break out the suicide cables and test that same
> device using line to ground.
>
> Depending on how your place is wired, you may find that under an actual load, your ground is really
> awful. A volt meter won't pick crappy ground connections unless you are actually running real
> current through it, so just reading 120 across hot and ground and saying "looks good" really
> doesn't count.

May well be worthwhile. But even with a good earth connection the
building ground can rise thousands of volts.

>
> Trying to suppress a surge with a $4 power strip connected though 5 junction boxes connected with
> BX cable can really just be a big joke.

Neither the IEEE or NIST agree. Both guides say plug-in suppressors,
used correctly, are effective. Plug-in suppressors with very high
ratings are readily and cheaply available. In the US you should only buy
suppressors listed under UL1449. UL tests include a testing to at least
a minimum floor of protection. UPSs with surge protection should also
have UL1449 listing.

==========
If there is a strong surge on power wires, with no power service
suppressor, at about 6kV there is arc-over from the hot busbars to the
service panel enclosure. After the arc is established, the arc voltage
is hundreds of volts. Since the enclosure is connected to
ground-neutral-earthing electrode, most of the surge energy is dumped to
earth. A surge is a short event, thus a relatively high frequency event.
The impedance of the branch circuit greatly limits the current to a
plug-in suppressor (unless the branch circuit is very short) and thus
limits the energy that can reach a plug-in suppressor. For both these
reasons the energy dissipated in a plug-in suppressor is surprisingly small.

Neither service entrance or plug-in suppressors work by absorbing the
surge energy. But in the process of protecting, some energy is absorbed.

--
bud--

==============================================================================
TOPIC: Unlabelled and disconnected mains primary wires
http://groups.google.com/group/sci.electronics.repair/t/827164e09c1645bf?hl=en
==============================================================================

== 1 of 2 ==
Date: Thurs, Jun 3 2010 11:15 am
From: David Nebenzahl

On 6/3/2010 2:45 AM Grant spake thus:

> On Thu, 3 Jun 2010 09:12:07 +0100, "N_Cook" <diverse@tcp.co.uk> wrote:
>
>> Grant <omg@grrr.id.au> wrote in message
>> news:tkne06ltbli2a5aij6qc112iti0ed8tntp@4ax.com...
>>
>>> What results from driving the secondary with a low voltage?
>>
>> My understanding of the term autotransformer is primary and
>> secondary electrically continuous, ie no electrical isolation
>>
> You're not looking for answers, are you?

He rarely is. Just sitting at the bar bending the ears of whatever poor
saps sitting nearby are willing to listen to his ramblings.

--
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)

== 2 of 2 ==
Date: Thurs, Jun 3 2010 2:25 pm
From: Cydrome Leader

N_Cook <diverse@tcp.co.uk> wrote:
> Cydrome Leader <presence@MUNGEpanix.com> wrote in message
> news:hu6geg$qkj$1@reader1.panix.com...
>> N_Cook <diverse@tcp.co.uk> wrote:
>> > About year 1999, USA make, for export
>> > In line , not 2 or more separate primary windings, DC ohms to nearest
> 0.1
>> > ohm. I'm assuming same gauge wire throughout
>> > Labelled by me as A,B,C,D,E crossplot (message souce maybe equispaced
> font)
>> >
>> > --- A B C D E
>> > A --- 9.2 8.5 12.5 1.5
>> > B 9.2 --- 0.6 3.6 7.6
>> > C 8.5 0.6 --- 4.2 7.6
>> > D 12.5 3.6 4.2 --- 11.1
>> > E 1.5 7.6 7.6 11.1 ---
>> >
>> >
>> > Would D-E / D-A be 220/240Vac or 230/250V ac?
>> > what would likely be the 110 or 130V interconnctions option ?
>> > Other than checking using a variac , any other tips ?
>>
>> you never mentioned what you're even talking about, or what it's from.
>>
>> Assuming it's something like an "international" linear power supply, there
> would be
>> windings for 100, 120 220 and 240 volts based off a combination of
> terminals. US made
>> transformers for domestic only use would generally max out at 3 or 4
> terminals for
>> 120/240 use.
>>
>> here's a diagram of how these international transformers work:
>>
>>
> http://www.slpower.com/Upload/Technical/20070404102642455201154_41-32512F_ML
> _Series.pdf
>
>
> That transformer type is the 2 separate primaries, not the subject of this
> thread.
> Does anyone have the generic name for these wasteful construction made in or
> for USA , for export kit ? the ones with a (electrically) continuous single
> primary winding

You're right- they must have just cheapened their transformers. Condor
stuff used to have the 5 terminal primary windings. If you can find a
manual for an older generation "international linear power supply" how
those windings are setup is diagrammed.

They're not a single winding though, and not nearly as wasteful as 50Hz
mains frequency when it comes to excessive use of materials and size.

==============================================================================
TOPIC: Unknown Turntable belt size - how to determine?
http://groups.google.com/group/sci.electronics.repair/t/c24e9d584f436d41?hl=en
==============================================================================

== 1 of 8 ==
Date: Thurs, Jun 3 2010 11:42 am
From: "William R. Walsh"

Hello all...

I recently dug up an old JC Penney MCS 2230 integrated stereo, and I'd like
to get the turntable going again. (Despite the source, it's a pretty nice
stereo system...the radio tuner works well, it seems to have about a 40Wx2
output power rating (which seems reasonable, having looked at the
internals), the cassette deck is a partial logic design with the ability to
skip ahead 1, 2 or 3 songs and the turntable itself is a linear tracking
type.)

Anyway, before I stored it, the turntable was in need of a new belt. I set
the belt aside and now it seems to be gone. I could have sworn that I read
about how to determine an unknown belt size in the FAQ, but I could not find
it just now. As best I remember, a string was used and placed around all the
components driven by the belt, after which a measurement was taken.

William

== 2 of 8 ==
Date: Thurs, Jun 3 2010 12:23 pm
From: D Yuniskis

Hi William,

William R. Walsh wrote:
> I recently dug up an old JC Penney MCS 2230 integrated stereo, and I'd like
> to get the turntable going again. (Despite the source, it's a pretty nice
> stereo system...the radio tuner works well, it seems to have about a 40Wx2
> output power rating (which seems reasonable, having looked at the
> internals), the cassette deck is a partial logic design with the ability to
> skip ahead 1, 2 or 3 songs and the turntable itself is a linear tracking
> type.)
>
> Anyway, before I stored it, the turntable was in need of a new belt. I set
> the belt aside and now it seems to be gone. I could have sworn that I read
> about how to determine an unknown belt size in the FAQ, but I could not find
> it just now. As best I remember, a string was used and placed around all the
> components driven by the belt, after which a measurement was taken.

I like using fine wire for that sort of thing. Strings stretch. :<

Of course, you will want to think about the number you get from
such a measurement. E.g., the actual belt size may be smaller
than you measure to allow for a snug fit (?)

Does 24.5mm sound right?

http://www.turntablebasics.com/belts/penney.html
http://www.vintage-electronics.cc/Pennys,_JC_%28MCS%29.html

== 3 of 8 ==
Date: Thurs, Jun 3 2010 12:45 pm
From: Meat Plow

On Thu, 03 Jun 2010 13:42:48 -0500, William R. Walsh ǝʇoɹʍ:

> Hello all...
>
> I recently dug up an old JC Penney MCS 2230 integrated stereo, and I'd
> like to get the turntable going again. (Despite the source, it's a
> pretty nice stereo system...the radio tuner works well, it seems to have
> about a 40Wx2 output power rating (which seems reasonable, having looked
> at the internals), the cassette deck is a partial logic design with the
> ability to skip ahead 1, 2 or 3 songs and the turntable itself is a
> linear tracking type.)
>
> Anyway, before I stored it, the turntable was in need of a new belt. I
> set the belt aside and now it seems to be gone. I could have sworn that
> I read about how to determine an unknown belt size in the FAQ, but I
> could not find it just now. As best I remember, a string was used and
> placed around all the components driven by the belt, after which a
> measurement was taken.
>
> William

String. I've used it on many turntables where the belt turned to mush.
Technics tt et al were one of my responsibilities at the warranty repair
center before the CD made them obsolete as far as new home audio system
sales were concerned. One other thing is the width of the belt is crucial
in many cases. That determines how the belt sometimes rides the motor
pulley and can cause problems including dismounting of the belt and speed
inconsistencies.

== 4 of 8 ==
Date: Thurs, Jun 3 2010 1:05 pm
From: zekfrivo@zekfrivolous.com (GregS)

In article <O9idnSsjYas_aprRnZ2dnUVZ_qCdnZ2d@mchsi.com>, "William R. Walsh" <newsgroups1@idontwantjunqueemail.walshcomptech.com> wrote:
>Hello all...
>
>I recently dug up an old JC Penney MCS 2230 integrated stereo, and I'd like
>to get the turntable going again. (Despite the source, it's a pretty nice
>stereo system...the radio tuner works well, it seems to have about a 40Wx2
>output power rating (which seems reasonable, having looked at the
>internals), the cassette deck is a partial logic design with the ability to
>skip ahead 1, 2 or 3 songs and the turntable itself is a linear tracking
>type.)
>
>Anyway, before I stored it, the turntable was in need of a new belt. I set
>the belt aside and now it seems to be gone. I could have sworn that I read
>about how to determine an unknown belt size in the FAQ, but I could not find
>it just now. As best I remember, a string was used and placed around all the
>components driven by the belt, after which a measurement was taken.

A turntable belt has a lot of stretch to it.

You could do a Google search and find the belt like I did..............
http://www.vintage-electronics.cc/Pennys,_JC_(MCS).html

== 5 of 8 ==
Date: Thurs, Jun 3 2010 1:08 pm
From: Jim Yanik

zekfrivo@zekfrivolous.com (GregS) wrote in
news:hu91s4$j52$1@usenet01.srv.cis.pitt.edu:

> In article <O9idnSsjYas_aprRnZ2dnUVZ_qCdnZ2d@mchsi.com>, "William R.
> Walsh" <newsgroups1@idontwantjunqueemail.walshcomptech.com> wrote:
>>Hello all...
>>
>>I recently dug up an old JC Penney MCS 2230 integrated stereo, and I'd
>>like to get the turntable going again. (Despite the source, it's a
>>pretty nice stereo system...the radio tuner works well, it seems to
>>have about a 40Wx2 output power rating (which seems reasonable, having
>>looked at the internals), the cassette deck is a partial logic design
>>with the ability to skip ahead 1, 2 or 3 songs and the turntable
>>itself is a linear tracking type.)
>>
>>Anyway, before I stored it, the turntable was in need of a new belt. I
>>set the belt aside and now it seems to be gone. I could have sworn
>>that I read about how to determine an unknown belt size in the FAQ,
>>but I could not find it just now. As best I remember, a string was
>>used and placed around all the components driven by the belt, after
>>which a measurement was taken.
>
> A turntable belt has a lot of stretch to it.
>
> You could do a Google search and find the belt like I
> did..............
> http://www.vintage-electronics.cc/Pennys,_JC_(MCS).html
>
>

OK,then after that,WHERE do you buy a new belt?
the store where I used to buy them locally has gone away. :-(

--
Jim Yanik
jyanik
at
localnet
dot com

== 6 of 8 ==
Date: Thurs, Jun 3 2010 1:25 pm
From: Meat Plow

On Thu, 03 Jun 2010 20:05:21 +0000, GregS ǝʇoɹʍ:

> n article <O9idnSsjYas_aprRnZ2dnUVZ_qCdnZ2d@mchsi.com>, "William R.
> Walsh" <newsgroups1@idontwantjunqueemail.walshcomptech.com> wrote:
>>Hello all...
>>
>>I recently dug up an old JC Penney MCS 2230 integrated stereo, and I'd
>>like to get the turntable going again. (Despite the source, it's a
>>pretty nice stereo system...the radio tuner works well, it seems to have
>>about a 40Wx2 output power rating (which seems reasonable, having looked
>>at the internals), the cassette deck is a partial logic design with the
>>ability to skip ahead 1, 2 or 3 songs and the turntable itself is a
>>linear tracking type.)
>>
>>Anyway, before I stored it, the turntable was in need of a new belt. I
>>set the belt aside and now it seems to be gone. I could have sworn that
>>I read about how to determine an unknown belt size in the FAQ, but I
>>could not find it just now. As best I remember, a string was used and
>>placed around all the components driven by the belt, after which a
>>measurement was taken.
>
> A turntable belt has a lot of stretch to it.

Depends on the individual TT. I've seen belts made of rubberized fabric
that didn't stretch at all. My old Rek-O-Kut TT had a belt that would not
stretcch at all made of some woven vulcanized rubber stuff. Any TT with a
heavy platter like the Rek-O is likely to have a stiff belt. Some of the
el-cheepo tables with aluminum platter will likely have a more stretchy
belt but it's not etched in stone.

== 7 of 8 ==
Date: Thurs, Jun 3 2010 9:31 pm
From: David Nebenzahl

On 6/3/2010 1:08 PM Jim Yanik spake thus:

> zekfrivo@zekfrivolous.com (GregS) wrote in
> news:hu91s4$j52$1@usenet01.srv.cis.pitt.edu:
>
>> In article <O9idnSsjYas_aprRnZ2dnUVZ_qCdnZ2d@mchsi.com>, "William R.
>> Walsh" <newsgroups1@idontwantjunqueemail.walshcomptech.com> wrote:
>>
>>>I recently dug up an old JC Penney MCS 2230 integrated stereo, and I'd
>>>like to get the turntable going again. (Despite the source, it's a
>>>pretty nice stereo system...the radio tuner works well, it seems to
>>>have about a 40Wx2 output power rating (which seems reasonable, having
>>>looked at the internals), the cassette deck is a partial logic design
>>>with the ability to skip ahead 1, 2 or 3 songs and the turntable
>>>itself is a linear tracking type.)
>>>
>>>Anyway, before I stored it, the turntable was in need of a new belt. I
>>>set the belt aside and now it seems to be gone. I could have sworn
>>>that I read about how to determine an unknown belt size in the FAQ,
>>>but I could not find it just now. As best I remember, a string was
>>>used and placed around all the components driven by the belt, after
>>>which a measurement was taken.
>>
>> A turntable belt has a lot of stretch to it.
>>
>> You could do a Google search and find the belt like I
>> did..............
>> http://www.vintage-electronics.cc/Pennys,_JC_(MCS).html
>
> OK,then after that,WHERE do you buy a new belt?
> the store where I used to buy them locally has gone away. :-(

Well, I'm lucky to live near Berkeley (yeah, *that* Berkeley), which
still has an old-time electronics store (Al Lasher's Electronics). Been
there since the 1940s, and they have all kinds of belts for turntables,
cassettes and VCRs.

I can't remember the name of the line of belts, but I could ask next
time I go there.

--
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)

== 8 of 8 ==
Date: Thurs, Jun 3 2010 9:38 pm
From: David Nebenzahl

On 6/3/2010 11:42 AM William R. Walsh spake thus:

> Hello all...
>
> I recently dug up an old JC Penney MCS 2230 integrated stereo, and I'd like
> to get the turntable going again. (Despite the source, it's a pretty nice
> stereo system...the radio tuner works well, it seems to have about a 40Wx2
> output power rating (which seems reasonable, having looked at the
> internals), the cassette deck is a partial logic design with the ability to
> skip ahead 1, 2 or 3 songs and the turntable itself is a linear tracking
> type.)
>
> Anyway, before I stored it, the turntable was in need of a new belt. I set
> the belt aside and now it seems to be gone. I could have sworn that I read
> about how to determine an unknown belt size in the FAQ, but I could not find
> it just now. As best I remember, a string was used and placed around all the
> components driven by the belt, after which a measurement was taken.

Instead of string, which does stretch, you might try a strip of paper.

Which reminds me of an old turntable I used to have. As a kid in Tucson,
not quite 20, I found a used turntable in a junk shop there. Cheap,
because it had no belt. Took it home, and being the resourceful lad I
was, I made a belt out of paper, the ends glued together with white
glue. Worked great! No problems with wow & flutter or rumble. The paper
belts lasted maybe a month or so before breaking. The bulb-shaped motor
pulley kept the belt tracking true.

Can't remember the brand, but it was an interesting turntable. Very
simple: just a deck, a motor, a spindle with inner and outer platters,
and an arm mounted on some kind of isolator. The arm had a single pivot.
Worked really well. (My poor man's AR.)

--
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)

==============================================================================
TOPIC: Sony PS-LX520 Turntable Power Supply Fault
http://groups.google.com/group/sci.electronics.repair/t/8383b4d4bdc7d72a?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Jun 3 2010 11:54 am
From: "William R. Walsh"

Hello all...

I recently cleaned up and restored to working order a Sony PS-LX520 linear
tracking turntable. After that it played beautifully until two nights ago
when I turned it on and found the "start" control to be unresponsive. As it
turned out, the lights that normally come on to indicate speed and playback
mode were also dead. It had been playing beautifully the night before.

The only sign of life was from the power button and the light bulb that is
used to tell the turntable how big the record is. The table motor was trying
to run, turning the platter very slowly. No part of the control panel works.

I popped it open and had a look inside to see if I could find anything
obviously wrong. Nothing was obviously distressed. There are three different
boards: one for audio, one for the logic control and a power/speed control
board. Power comes into the unit from a multi-tapped transformer, and this
seems to be OK. Markings on the logic circuit board seem to indicate that
there should be -16 volts, +16 volts and +6 volts from the speed
control/power board. I have the two sixteen volt supplies and they are very
close to being dead on. The six volt supply is completely missing! Most of
the connectors are point to point wiring, with the wires placed into plastic
guides and soldered to the board. As they look difficult to remove, I have
not attempted to see if something is loading down the +6 volt supply.
Nothing is getting hot.

I have a service manual coming. Already I have been looking at the two
filter capacitors on the power/speed control board. They are both 25 volt,
1000uF units. One holds its charge nicely and long after power off. The
other one discharges much more quickly, but not quickly enough to make me
think that a problem is draining it.

Every date code in the unit suggests it was made around the middle of 1987.

Has anyone worked on this turntable or a similar model and seen this
problem?

William

==============================================================================
TOPIC: Rubber keyboard contact repair
http://groups.google.com/group/sci.electronics.repair/t/61db4df7250c5d17?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Jun 3 2010 1:07 pm
From: "Gareth Magennis"

"Gareth Magennis" <sound.service@btconnect.com> wrote in message
news:wJ-dnQh7OIbG35vRnZ2dnUVZ7tGdnZ2d@bt.com...
> Hi,
>
> anyone geting good results rejuvenating worn keyboard contacts? I'm
> talking the large ones you find on music keyboards, drum machines etc.
> Particularly ones where you can't buy the contact rubbers any more ;)
>
> I once bought some liquid paint on stuff specifically designed to do this,
> it was VERY expensive and didn't work.
>
> I am in the UK if that makes a difference.
>
>
> Cheers,
>
>
> Gareth.
>

Thanks to all. This is a largeish pad on a Drum Machine. I had a quick go
at slicing off part of the knackered pad and slicing off the conductive
nipple from a keyboard contact strip with a view to gluing some of them on.

Rapidly came to the conclusion I could not charge a customer money for a
complete bodge job I could not guarantee to work past next week. This is
the Start/Stop button which takes a hammering.

One more piece of old toot bites the dust.

==============================================================================
TOPIC: Keep coin cells away from kids
http://groups.google.com/group/sci.electronics.repair/t/5d93e4504cdeacef?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Jun 3 2010 4:02 pm
From: bob

http://xrl.in/5ipo

http://www.edn.com/blog/PowerSource/39179-Tiny_lithium_coin_cell_batteries_act_like_lye_if_swallowed_by_the_very_young.php

bob

==============================================================================
TOPIC: 2 pin vs 4 pin bulb
http://groups.google.com/group/sci.electronics.repair/t/976f61f27bcf629e?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Jun 3 2010 8:07 pm
From: "don"

"nesesu" <neil_sutcliffe@telus.net> wrote in message
news:41d7151f-c60a-4d37-9278-f6dc6fdd58a2@l6g2000vbo.googlegroups.com...

Don, that photo is of the ballast, not the socket.

Some sockets have the pins crimped to the stranded wire then poked
into the housing. That type is often non-removeable or requires a
special tool to release the pin.

Neil S.

ok thanks.... if you follow the link it would bring you to the pic of the
socket which was a .pdf form so I didn't know if a direct link could be done

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

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 9 topics - digest

No Response to "sci.electronics.repair - 25 new messages in 9 topics - digest"

Post a Comment

Blog Roll

Blog Archive