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

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

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Today's topics:

==============================================================================
TOPIC: Looking for PS glitch with Tek scope?
http://groups.google.com/group/sci.electronics.repair/t/ecf659bcc56a1548?hl=en
==============================================================================

== 1 of 3 ==
Date: Thurs, Jun 3 2010 1:18 am
From: Gary Walters

I have a machine in that I suspect the PS (+24vdc) is sagging under load
which is causing all kind of havoc with the digital circuits. The load is
brief, so I've not been able to capture it with a DMM.

I borrowed a Tek TDS410 digitizing scope. It's quite complex (to me, anyway)
and I'm not sure how to view the PS such that I can capture a sagging output.

I've used a 465 decades ago and a 2467 more recently, but the digitizing
scopes are new to me.

There's all kinds of capture modes (sample; peak detect; envelope; average),
measurement modes (high; low; max; min; 16 others), and trigger modes (auto;
normal; rising edge; falling edge).

I presume that I set the trigger just below the output voltage (ie, 11.80v),
falling edge, and activate the load. Beyond that, it's a mystery to me.

The site is a bit of a drive, so I've been practicing in my shop with a
stand-alone PS.

I've looked on-line for an operator's guide, but all I've been able to find
is a service manual (TDS410/420/460) which has not much in the way of setup
and operation.

Any suggestions regarding the best combination of features to use for this
simple task would be most appreciated.

Thanks.
GW

== 2 of 3 ==
Date: Thurs, Jun 3 2010 6:57 am
From: Winston

On 6/3/2010 1:18 AM, Gary Walters wrote:
> I have a machine in that I suspect the PS (+24vdc) is sagging under load
> which is causing all kind of havoc with the digital circuits. The load is
> brief, so I've not been able to capture it with a DMM.
>
> I borrowed a Tek TDS410 digitizing scope. It's quite complex (to me, anyway)
> and I'm not sure how to view the PS such that I can capture a sagging output.

http://www2.tek.com/cmswpt/madetails.lotr?ct=MA&cs=mur&ci=9211&lc=EN

Top of the control panel to the right of the display is the
'General Purpose' knob. Just to it's right is a button labeled
'Autoset'. Hang your probe on the power supply and press the
'Autoset' button. Your scope will now be initialized at a good
starting point. From there, adjust trigger polarity and level,
'sweep' speed, memory depth. Bob's your uncle.

If you get into a puzzling situation where you can't see the trace
or can't get the scope to trigger, just pop the 'Autoset' button
again and you will be getting good data in no time.

I really like the Tek TDS series. Clearly the user interface was
designed by an actual scope user rather than just a software
(Cough Agilent cough) engineer.

--Winston

== 3 of 3 ==
Date: Thurs, Jun 3 2010 7:32 am
From: George Herold

On Jun 3, 4:18 am, Gary Walters <gwp...@yahoo2.cz> wrote:
> I have a machine in that I suspect the PS (+24vdc) is sagging under load
> which is causing all kind of havoc with the digital circuits. The load is
> brief, so I've not been able to capture it with a DMM.
>
> I borrowed a Tek TDS410 digitizing scope. It's quite complex (to me, anyway)
> and I'm not sure how to view the PS such that I can capture a sagging output.
>
> I've used a 465 decades ago and a 2467 more recently, but the digitizing
> scopes are new to me.
>
> There's all kinds of capture modes (sample; peak detect; envelope; average),
> measurement modes (high; low; max; min; 16 others), and trigger modes (auto;
> normal; rising edge; falling edge).

Put it in sample mode and forget the rest for now. Make sure the
input is set to DC couple.

>
> I presume that I set the trigger just below the output voltage (ie, 11.80v),
> falling edge, and activate the load. Beyond that, it's a mystery to me.

Can you trigger on whatever is causing the brief load? This would
make your life easier. If not then as you say set the trigger level
just below the voltage level before the load is activated. If you
first put the scope in auto trigger you will see the DC level. Set
the trigger level just below this and change the triggering to normal
(or maybe single shot) You'll want to trigger on the falling edge.
Now all you have to do is set the time base.. probably you'll have to
play around with different time bases since you don't know how long
the voltage sag lasts.

You can use the DC offset knob and Volts/div knob to zoom in on the
transient behavior.

>
> The site is a bit of a drive, so I've been practicing in my shop with a
> stand-alone PS.
>
> I've looked on-line for an operator's guide, but all I've been able to find
> is a service manual (TDS410/420/460) which has not much in the way of setup
> and operation.
>
> Any suggestions regarding the best combination of features to use for this
> simple task would be most appreciated.
>
> Thanks.
> GW

Good luck,

George H.

(PS I hate the autoset button, I wish I could tape mine over. Every
once in a while I hit it by accident and then curse.)

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

== 1 of 5 ==
Date: Thurs, Jun 3 2010 2:19 am
From: Ron

On 03/06/2010 08:27, N_Cook 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
>
>

Multitap?

== 2 of 5 ==
Date: Thurs, Jun 3 2010 2:30 am
From: "N_Cook"

Ron <ron@lunevalleyaudio.com> wrote in message
news:z5KdnW0VXPQ_7prRnZ2dnUVZ8hKdnZ2d@bt.com..

> Multitap?

You can have multitaps on dual primary ones for variants on the theme of
110/240V, so not an exclusive term

== 3 of 5 ==
Date: Thurs, Jun 3 2010 2:45 am
From: Grant

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...
>> On Thu, 3 Jun 2010 08:27:03 +0100, "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_M
>L
>> >_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
>> >
>> Autotransformer.
>>
>> What results from driving the secondary with a low voltage?
>>
>> Grant.
>> --
>> http://bugs.id.au/
>
>
>My understanding of the term autotransformer is primary and secondary
>electrically continuous, ie no electrical isolation
>
You're not looking for answers, are you?

Grant.
--
http://bugs.id.au/

== 4 of 5 ==
Date: Thurs, Jun 3 2010 4:46 am
From: "Phil Allison"

"Nutcase Kook is So Full of Shit "

> 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
>

** Wot a load of utter bollocks
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Most audio amps made in the ** UK ** between the mid 1960s and late 1990s
had
multi-voltage, single winding AC transformers.

Check any old schem from Marshall, Vox or Sugden etc, et alia.

http://www.audiomisc.co.uk/JES/A21series2/A21series2.html

http://www.schematicheaven.com/marshallamps/jcm800_lead_mstvol_50w_2204.pdf

http://www.schematicheaven.com/voxamps/ac301960.pdf

http://www.schematicheaven.com/voxamps/ac151960.pdf

Nutcase Kook is Soooooo... Full of Shit

.... Phil

== 5 of 5 ==
Date: Thurs, Jun 3 2010 4:48 am
From: "Phil Allison"

Nutcase Kook is Sooooo Full of Shit

>> Multitap?
>
>
> You can have multitaps on dual primary ones for variants on the theme of
> 110/240V, so not an exclusive term

** Nutcase Kook is Sooooooooooooo Full of Shit !!!

.... Phil

==============================================================================
TOPIC: The problem was NOT what I expected.
http://groups.google.com/group/sci.electronics.repair/t/cc4ea67fc99086a6?hl=en
==============================================================================

== 1 of 2 ==
Date: Thurs, Jun 3 2010 2:10 am
From: bz

A somewhat interesting case, troubleshooting and 'repair' of an audio amp.

I was presented with a "dead" 'classic' transistorized audio amp.

The owner had checked one of the fuses that was located in the back panel
power socket. There were also two fuses on the main board, also good.

The owner had forgotten to run off the amp and a thunderstorm had come
through the area. He found the amp totally unresponsive when he came home.

Hm, fuse or diode or switch? No visible signs of damage. No smell of smoke.

The amp weighs close to 30 pounds due to the HUGE toroidal shaped power
transformer.

My first step was to try to verify the power circuitry.

I didn't find any AC voltage at the screws of the terminal strip.

Aha, I though, as I started tracing the AC input that came from the back
panel to the power switch and then through a thermal cutout device on the
large heat sink, to the terminal strip. It must be the switch or the
thermal cutout.

Switching the meter to ohms and removing the power cord, I confirmed that
the safety ground was contiguous and that the neutral was also.
But I could not find continuity through the hot side to anything. Must be
the thermal cutout mounted on the transistor heat sink!

I finally cut a small hole in the insulation on the wires leading to the
thermal device. (no needle pointed test leads available)
Hm. Thermal cutout was ok.

Maybe the switch? Pulling the back panel fuse, I confirmed that I had
continuity to the amp end of the fuse holder when the switch was on, but
the hot end of the fuse holder showed NO connection to the adjacent power
plug pin!

Pulling back the 'boot' that covered the back of the panel power plug,
everything looked fine but there was no continuity between the fuse holder
and the strap that tied it to the power plug pin. A few seconds with the
soldering iron and everthing now checks ok!

The solder joint ON the back panel power plug had failed without any
visible sign!

--
bz 73 de N5BZ k

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

== 2 of 2 ==
Date: Thurs, Jun 3 2010 8:18 am
From: nesesu

On Jun 3, 2:10 am, bz <bz+...@ch100-5.chem.lsu.edu> wrote:
> A somewhat interesting case, troubleshooting and 'repair' of an audio amp.
>
> I was presented with a "dead" 'classic' transistorized audio amp.
>
> The owner had checked one of the fuses that was located in the back panel
> power socket. There were also two fuses on the main board, also good.
>
> The owner had forgotten to run off the amp and a thunderstorm had come
> through the area. He found the amp totally unresponsive when he came home.
>
> Hm, fuse or diode or switch? No visible signs of damage. No smell of smoke.
>
> The amp weighs close to 30 pounds due to the HUGE toroidal shaped power
> transformer.
>
> My first step was to try to verify the power circuitry.
>
> I didn't find any AC voltage at the screws of the terminal strip.
>
> Aha, I though, as I started tracing the AC input that came from the back
> panel to the power switch and then through a thermal cutout device on the
> large heat sink, to the terminal strip. It must be the switch or the
> thermal cutout.
>
> Switching the meter to ohms and removing the power cord, I confirmed that
> the safety ground was contiguous and that the neutral was also.
> But I could not find continuity through the hot side to anything. Must be
> the thermal cutout mounted on the transistor heat sink!
>
> I finally cut a small hole in the insulation on the wires leading to the
> thermal device. (no needle pointed test leads available)
> Hm. Thermal cutout was ok.
>
> Maybe the switch? Pulling the back panel fuse, I confirmed that I had
> continuity to the amp end of the fuse holder when the switch was on, but
> the hot end of the fuse holder showed NO connection to the adjacent power
> plug pin!
>
> Pulling back the 'boot' that covered the back of the panel power plug,
> everything looked fine but there was no continuity between the fuse holder
> and the strap that tied it to the power plug pin. A few seconds with the
> soldering iron and everthing now checks ok!
>
> The solder joint ON the back panel power plug had failed without any
> visible sign!
>
> --
> bz 73 de N5BZ k
>
> please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
> infinite set.

BZ, it is not uncommon for the plating on the terminal of the power
connector to fail at the interface between the plated metal and the
base metal, especially under solder. The outward appearance seems
perfect, bet when the solder is removed there is typically a black
surface on the base metal that seems to be an excellent insulator.
This same problem also occurs on the pins of TO-3 transstors soldered
into PCBs and on terminal pins staked in to PCBs.
Some of the worst offenders I have come across are tin plating on
brass and tin and/or nickel plating on steel.

Neil S.

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

== 1 of 10 ==
Date: Thurs, Jun 3 2010 3:12 am
From: "Michael A. Terrell"

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.

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

== 2 of 10 ==
Date: Thurs, Jun 3 2010 4:27 am
From: "Michael Kennedy"

"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.

== 3 of 10 ==
Date: Thurs, Jun 3 2010 5:34 am
From: mike

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.

== 4 of 10 ==
Date: Thurs, Jun 3 2010 5:41 am
From: mike

Michael Kennedy wrote:

>
> 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 broaden your knowledge.
>
> Mike

The scsi I have has a different connector than the ones in the drive
bay. It has a cdrom (it's kind of odd, looks like a laptop cd-drive)
that has a connector that's the same as well as a back-plane
connector that would fit it,

Thanks for the suggestions, I guess I was in need of a push to get
around to doing something with it.

Another Mike

== 5 of 10 ==
Date: Thurs, Jun 3 2010 5:54 am
From: mike

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.

Thanks for the ideas,
Mike

== 6 of 10 ==
Date: Thurs, Jun 3 2010 6:08 am
From: Meat Plow

On Thu, 03 Jun 2010 05:54:42 -0700, mike ǝʇoɹʍ:

> 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.
>
> Thanks for the ideas,
> Mike

You might want to go to Wikipedia and do a little reading on the history
of SCSI devices. I used SCSI in my NT4 workstation back in 1997.
There have been several different varieties of SCSI developed in the past
decade or so and you'll need to identify the different connectors and how
to properly terminate the SCSI chain.

== 7 of 10 ==
Date: Thurs, Jun 3 2010 8:16 am
From: AZ Nomad

On Thu, 3 Jun 2010 17:15:28 +0900, Michael Kennedy <mike@nospam.com> 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.

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.

== 8 of 10 ==
Date: Thurs, Jun 3 2010 9:57 am
From: mike

Meat Plow wrote:

>
> You might want to go to Wikipedia and do a little reading on the history
> of SCSI devices. I used SCSI in my NT4 workstation back in 1997.
> There have been several different varieties of SCSI developed in the past
> decade or so and you'll need to identify the different connectors and how
> to properly terminate the SCSI chain.

good idea, I think I'll do that.
Thanks,
Mike

== 9 of 10 ==
Date: Thurs, Jun 3 2010 10:04 am
From: mike

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

== 10 of 10 ==
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.

==============================================================================
TOPIC: RCA chassis ATC010A
http://groups.google.com/group/sci.electronics.repair/t/6ea1ceadfb8a0425?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Jun 3 2010 8:18 am
From: Gary Woodruff

Hello, I have an RCA chassis # ATC010A. The set will power up and
display a pic for about 5 seconds before turning off. I can hold any
front panel button (vol, channel, etc) and the set will stay powered on
until the button is released. I know these sets have problems with the
front panel assembly being defective and causing on/off by itself
problems. I tried powering on set and disconnecting the cable to the
front panel button assembly but the set still powers off after a 5
seconds of picture. I have also checked for cold solder joints and
replaced the HOT. Anyone have any suggestions or a print?

Thanks, Gary

==============================================================================
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 8:27 am
From: nesesu

On Jun 2, 5:53 pm, "don" <d...@panix.com> wrote:
> What are the advantages of a 4pin vs a 2pin bulb..... the manufacturer of my
> task light used a 2 pin bulb but the socket is made to accept a 4 pin......
> Also..... the socket wire connections are of the type Leviton as seen in
> this photo.....http://bplusl.com/html/nu6-1128eol.htm
>
> I am trying to replace the ballast.... does anyone know how to unhook the
> wires from this lamp holder?

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.

==============================================================================
TOPIC: Simple hack to get $500 to your home.
http://groups.google.com/group/sci.electronics.repair/t/b0b9cb16ad105ccc?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Jun 3 2010 8:44 am
From: SUHASINI

Simple hack to get $500 to your home at http://uslatest.tk

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

==============================================================================
TOPIC: replacing the LCD screen on a PSP
http://groups.google.com/group/sci.electronics.repair/t/2d49671f6f9f5281?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Jun 3 2010 9:08 am
From: Peter

lsmartino wrote:
> Yes, you are right! Believe it or not, I didn´t noticed the middle
> horizontal line :-(

So does anyone have any knowledge about screen replacement
to offer?
Thanks, ... Peter E.

==============================================================================
TOPIC: See Hot Sexy Star Aishwarya Nude Bathing Videos In All Angles.
http://groups.google.com/group/sci.electronics.repair/t/fda2aa9fa2e65ed3?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Jun 3 2010 9:10 am
From: KAJOL

See Hot Sexy Star Aishwarya Nude Bathing Videos In All Angles.
at http://uknews.tk

Due to high sex content,i have hidden the videos in an image. in that
website on left side below search box click on image and watch
videos in all angles.please dont tell to anyone.

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

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