sci.electronics.repair - 15 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: Driveway sensor, model 917-1, mfg. around 1993 by "Detector Systems"
http://groups.google.com/group/sci.electronics.repair/t/502c70dec1b2d85e?hl=en
==============================================================================

== 1 of 4 ==
Date: Thurs, Oct 14 2010 11:53 am
From: klem kedidelhopper

On Oct 14, 1:21 am, nesesu <neil_sutcli...@telus.net> wrote:
> On Oct 13, 8:42 pm, "hrhofm...@att.net" <hrhofm...@att.net> wrote:
>
> > How did you locate the manual?
>
> Third item shown when I Googled "Detector Systems model 917-1".
>
> Neil S.

Having trouble posting. I don't know if this is going through.
Neil
Last night I connected about 100 feet of 2 conductor 16AWG. sheilded
cable to the test loop and ran it into the house. The sheild is
grounded on the controller end. The modified coil with three turns and
a 4 ft by 8 ft. perimeter now and a total length of approximately 72
feet is laying in the driveway.With the dip switch sensitivity
combination I found the controller seems to detect a vehicle on the
approach every time now. We're in New Hampshire so the real test will
probably come when the coil is buried and the ground is frozen with
ice and snow on top.
Thank you very much for finding and sending me that manual. The
interesting thing is that although it is indeed for a "917-1", it is
marked 3M. I guess that 3M must have bought out detector Systems and
simply put their own name on the unit. It does appear to be the same
unit as mine though.
In comparing the manual 's coil specifications to mine the manual
calls for a coil consisting of an 18" x 54" loop with 5 or 6 turns of
16AWG. cable. Therefore the total amount of wire in that coil will be
[(18+54) X 2] x 6
[(18+54) x 2] = 144
Then 144 X 6 = 864
854/ 12 = 72ft.
So it seems that although their coil uses more turns of wire, the
total wire length of theirs and my present test coil is the same. In
your opinion, what is the significance of more turns as opposed to
larger perimeter? I'm concerned of course with system reliability and
naturally repeatability. If this thing fails to detect even one time
it will be useless to us. And I certainly won't be digging it up in
January. Would I be better off with building and burying their smaller
coil with more turns or the one I'm trying out now? Thanks, Lenny.

== 2 of 4 ==
Date: Thurs, Oct 14 2010 4:13 pm
From: nesesu

On Oct 14, 9:55 am, klem kedidelhopper <captainvideo462...@gmail.com>
wrote:
> On Oct 14, 1:21 am, nesesu <neil_sutcli...@telus.net> wrote:
>
> > On Oct 13, 8:42 pm, "hrhofm...@att.net" <hrhofm...@att.net> wrote:
>
> > > How did you locate the manual?
>
> > Third item shown when I Googled "Detector Systems model 917-1".
>
> > Neil S.
>
> Neil
> Last night I connected about 100 feet of 2 conductor 16AWG. sheilded
> cable to the test loop and ran it into the house. The sheild is
> grounded on the controller end. The modified coil with three turns and
> a 4 ft by 8 ft. perimeter now and a total length of approximately 72
> feet is laying in the driveway.With the dip switch sensitivity
> combination I found the controller seems to detect a vehicle on the
> approach every time now. We're in New Hampshire so the real test will
> probably come when the coil is buried and the ground is frozen with
> ice and snow on top.
> Thank you very much for finding and sending me that manual. The
> interesting thing is that although it is indeed for a "917-1", it is
> marked 3M. I guess that 3M must have bought out detector Systems and
> simply put their own name on the unit. It does appear to be the same
> unit as mine though.
> In comparing the manual 's coil specifications to mine the manual
> calls for a coil consisting of an 18" x 54" loop with 5 or 6 turns of
> 16AWG. cable. Therefore the total amount of wire in that coil will be
> [(18+54) X 2] x 6
> [(18+54) x 2] = 144
> Then 144 X 6 = 864
> 854/ 12 = 72ft.
> So it seems that although their coil uses more turns of wire, the
> total wire length of theirs and my present test coil is the same. In
> your opinion, what is the significance of more turns as opposed to
> larger perimeter? I'm concerned of course with system reliability and
> naturally repeatability. If this thing fails to detect even one time
> it will be useless to us. And I certainly won't be digging it up in
> January. Would I be better off with building and burying their smaller
> coil with more turns or the one I'm trying out now? Thanks, Lenny.

Yes, Lenny, all three posting came through okay.
I would certainly reconfigure your coil to match the one specified in
the manual. Since the wire length is similar, it would not be a big
issue to to change it now and try that out. The manual does specify a
nominal loop inductance of 30 to 1000uH, so there is a lot of margin
designed in. If you have an inductance bridge, you could measure the
inductance of your existing coil and see where it falls in that range.
As far as operating in the cold/wet/ice, one will have to see, but
since it is self tuning it should be fine.
You say it must operate EVERY time, but that is expecting too much of
it. I would expect better than 99.9% sensing of 'normal' cars but
motorcycles and the like can be 'IFFY'. You will also have to expect
the occasional false trip due to abrupt weather changes [sudden rain
storm for example].

Neil

== 3 of 4 ==
Date: Thurs, Oct 14 2010 4:48 pm
From: JeffM

>klem kedidelhopper posted 3 times:
>>Would I be better off with building and burying
>>their smaller coil with more turns or[...]
>>
nesesu wrote:
>Yes, Lenny, all three posting came through okay.
>
Heh. Google Groups' quasi-annual takedown for maintenance.
Roughly 10AM - 3PM today.

Impatient posters using a Web interface to Usenet
should poll ANOTHER one of those *before* posting *again*.
(Google is NOT the only game in town.)
Here are some with reasonable latency:
http://www.electronicskb.com/Default.aspx
http://www.electrondepot.com/

== 4 of 4 ==
Date: Thurs, Oct 14 2010 8:37 pm
From: klem kedidelhopper

On Oct 14, 7:48 pm, JeffM <jef...@email.com> wrote:
> >klem kedidelhopper posted 3 times:
> >>Would I be better off with building and burying
> >>their smaller coil with more turns or[...]
>
> nesesu wrote:
> >Yes, Lenny, all three posting came through okay.
>
> Heh. Google Groups' quasi-annual takedown for maintenance.
> Roughly 10AM - 3PM today.
>
> Impatient posters using a Web interface to Usenet
> should poll ANOTHER one of those *before* posting *again*.
> (Google is NOT the only game in town.)
> Here are some with reasonable latency:http://www.electronicskb.com/Default.aspxhttp://www.electrondepot.com/

Neil
When I said "every time" I wasn't thinking of motorcycles. My wife's
business which is run out of part of our home is a gift shop catering
primarily to women. The shop is off the main road. So considering the
clientele we're really not expecting too many bikes in here, and if
the occaisional one does come through and does not get detected then
its not the end of the world. No, I was referring to the mass of a
typical automobilie. The issue is that there are sometimes long
periods of time when there is no business. she doesn't want to have to
stay down there waiting for a customer to show up. This sensor will
allow her to turn out the lights and be in some other part of the
house until the alarm sounds. She can then run downstairs, turn on the
lights and be "open for business" And so far with the loop laying on
the ground its worked every time. You were right on the money with
your idea of three turns and a 4 X 8 footprint which is the 72 feet
the book talks about. I don't have an impedance bridge.so I can't
directly measure inductance, however the instructions did mention an
operating frequency of between 30 and 60 KHZ. I suppose that I could
look at this with the scope, determine exactly what it is and then
figure out a way to determine inductance if I really want to. But for
the time being I'm going to rewind the coil for the 6 turns the
instructions call for.
So now I need to ask for your advice again. Last year I rewired my
well. I pulled up 175 feet of the old wire and replaced it. The
conductors in that wire were continuous however the insulation was
scuffed and scraped and in some cases down to bare copper and no
longer servicable for well application. However I kept it around to
use for projects, such as this one..Well wire if you've ever worked
with it is typically three twisted conductors made from 14AWG. This
wire is apparently impervious to moisture because it runs right down
the well casing throught the water to the submersible pump. My present
test coil is made from some of that old wire.unwound to single srand.
The scuffed parts were taped up in places for purposes of this test
but it is not in good enough condition to put directly into the
ground. I have a gravel driveway and ultimately I will need to bury
the final coil amidst this abrasive material.. I could get some more
of this well wire or the instructions say that you can directly bury
THHN or a similar type of wire. My concern though is the dirt, stones,
sand, etc. which would be in constant cantact and abrading this wire.
I think that I would like to encase it somehow. ideally in PVC. Then
have some kind of an underground junction box to connect my sheilded
cable to. Do you have any ideas as to how to do this? Lenny

==============================================================================
TOPIC: Transistor ID...
http://groups.google.com/group/sci.electronics.repair/t/206b5827a2414f1b?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Oct 14 2010 12:52 pm
From: Cydrome Leader

tmcw <tmcwboards@gmail.com> wrote:
> Posted this at sci.electronics.basics; got redirected to here. Hope
> someone can help:
>
> Have a broken inverter on a 2000fp Dell LCD monitor.
>
> One of the transistors is visibly fried on the board.
>
> Can anyone help me ID what type of transistor it is, and where I
> could
> source a replacement?
>
> Markings on it: DT QX
>
> Q12 in the photo linked below.
>
> Photo: http://i663.photobucket.com/albums/uu357/polyfusion/2000fp_Invert.jpg
>
> Thanks.

I sort of like the layout of that board.

I was just working on a Vivitar 285 camera flash- talk about pile of junk
that looks like, and was designed in the 1970s. Parts crammed in every
direction, wires all over the place, strange daughterboards, junk and
spacers that just fall out once you open it etc. Yuck.

==============================================================================
TOPIC: mis-connecting audio and composite video
http://groups.google.com/group/sci.electronics.repair/t/6df650a80c93f7fd?hl=en
==============================================================================

== 1 of 2 ==
Date: Thurs, Oct 14 2010 11:18 am
From: D Yuniskis

Ulysses wrote:
> What happens (in terms of damage) if you connect an audio signal to a
> composite video input or composite video to an audio input?

Presumably, this is a single-ended audio signal? What level is it?
E.g., "line out" shouldn't cause problems with RS170 video *in*.
Likewise, connecting the video to "line in" should be safe.

OTOH, depending on what sort of video device you are connecting
to and the audio signal "while connected", the video device
could misinterpret sync information in the "audio" signal...

Of course, you won't be able to "watch" the audio signal or *listen*
to the video...

> I have an old Sony camcorder that has single-channel audio + composite
> video out from a 3.5 mm (1/8") jack. The "correct" cable has a 3.5 mm
> plug one one end and a black RCA plug (audio) and a yellow RCA plug
> (composite video) on the other ... and costs $17 or more.

You can probably pick up something like this for $1 at deal extreme or
their ilk. *If* you have some personal need for yellow and black :>
(some are yellow and white)

> I have a 3.5 mm to stereo RCA (red and black) audio cable. I can't see
> why this cable wouldn't work, but I don't know if the black on my cable
> corresponds to the black connector on the "correct" cable or to the
> yellow connector. So it's possible that I may connect the audio signal
> to the composite video input of my monitor. Is there a risk of damage
> to the monitor?

Why don't you try connecting the the "suspected audio" cable to
some disposable *audio* device if you fear damage to your
(more expensive) monitor? Or, a 'scope? (i.e., hook up
camcorder. Speak into microphone while recording with
pauses between your words/sentences. You can then look at
either signal (audio or video) and should be able to recognize
the constant "AC" of a video signal -- even without syncing the
scope! -- vs. the bursts of "Hello"... "Testing"... "lah-dee-dah"...
that you recorded on the audio track.

All this without having to know anything about electronics! :>

== 2 of 2 ==
Date: Thurs, Oct 14 2010 8:35 pm
From: stratus46@yahoo.com

On Oct 14, 7:51 am, Ulysses <ulysse...@hotmail.com> wrote:
> What happens (in terms of damage) if you connect an audio signal to a
> composite video input or composite video to an audio input?
>
> I have an old Sony camcorder that has single-channel audio + composite
> video out from a 3.5 mm (1/8") jack. The "correct" cable has a 3.5 mm
> plug one one end and a black RCA plug (audio) and a yellow RCA plug
> (composite video) on the other ... and costs $17 or more.
>
> I have a 3.5 mm to stereo RCA (red and black) audio cable. I can't see
> why this cable wouldn't work, but I don't know if the black on my cable
> corresponds to the black connector on the "correct" cable or to the
> yellow connector. So it's possible that I may connect the audio signal
> to the composite video input of my monitor. Is there a risk of damage
> to the monitor?

Nothing bad but the sound is horrible and the picture sucks. Try it. I
have for silliness. Signal levels are comparable. The 75 ohm
terminator on the video input will load the audio but not damage it.

The audio cable is not 75 ohm transmission line. You will get video
through it but the edges may get smeary or have trailing edge rings.
Niether case is optimum.

G²

==============================================================================
TOPIC: What should be the value of the resistance?
http://groups.google.com/group/sci.electronics.repair/t/0e24671f1705909d?hl=en
==============================================================================

== 1 of 2 ==
Date: Thurs, Oct 14 2010 11:09 am
From: D Yuniskis

supahi mahanta wrote:
> Small signal voltage gain by one small resistance connected to emitter
> through a large by passed resistance and junction to base resistance
> for negative feedback. If small R is 0.22K and Rc=10K. What should be
> its value?

Flip to the back of the book and see if there is a section
called "Answers to selected exercises"...

== 2 of 2 ==
Date: Thurs, Oct 14 2010 11:30 pm
From: supahi mahanta

On Oct 14, 9:27 pm, "William Sommerwerck" <grizzledgee...@comcast.net>
wrote:
> >> You need to find a book on transistor circuit design. A college-level
> >> text should be okay. The math isn't complex, so you shouldn't have
> >> trouble understanding it.
> > His question looks to have been copied from a poorly written
> > textbook.
>
> He's probably asking for someone to do his homework.

Thank you so much for your valuable hint sir. This is not a homework
copied from any textbook. This arise in my mind while making a home
made material and your hint helped me a lot. Thank you.

==============================================================================
TOPIC: can i bring new life to this old VCR?
http://groups.google.com/group/sci.electronics.repair/t/b80bdaff85d3a3a6?hl=en
==============================================================================

== 1 of 2 ==
Date: Thurs, Oct 14 2010 5:00 pm
From: nucleus

good suggestion. where can i get such material for "cutting my own"?
i have substituted a rubber band for the belt, it has solved the
problem
functionally but it is not the right size or durometer and eventually
may
damage the bearing surfaces of the pulleys.

On Oct 12, 3:33 am, "N_Cook" <dive...@tcp.co.uk> wrote:
> Mike WB2MEP <michael.w.appenzel...@lmco.com> wrote in message
> Consider cutting your own as they tend to
> be quite large cross-section, square for round cross-section replacement
> does not usually matter.

== 2 of 2 ==
Date: Fri, Oct 15 2010 12:30 am
From: "N_Cook"

nucleus <rose122550@yahoo.com> wrote in message
news:d857ce16-47cf-4074-b7a4-9360a60ea172@f25g2000yqc.googlegroups.com...
good suggestion. where can i get such material for "cutting my own"?
i have substituted a rubber band for the belt, it has solved the
problem
functionally but it is not the right size or durometer and eventually
may
damage the bearing surfaces of the pulleys.

Every time I passed bike / motorcycle/ car / lorry facility that changed
tyres I asked for any scrap inner tubes. Cut a working band from each a
dumped the rest in the garden shed. I now have a range of diameters from
about 1 inch to 10 inch. Often a slightly diagonal cut is possible for
intermediary diameters.
Details of "bean slicer" etc on my tips files off below, for reducing
thickness for flat bands etc.
No wasting time now on fruitless www hunts

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://diverse.4mg.com/index.htm

==============================================================================
TOPIC: wholesale name brand kids timberland shoes on www.jialiuonline.com
http://groups.google.com/group/sci.electronics.repair/t/cf859a24f6417f94?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Oct 14 2010 7:32 pm
From: jialiushoes

welcome to http://www.jialiuonline.com or feel

All the products are listed as following:

Footwear:
NikeAF1,Airmax,Shox,Adidas,Timberland,Puma,Gucci,Prada,LV,Chanel,Lacos

te,Lebron,Kobe,Rift,
Dunk SB, Nike Women Shoes, Nike Children Shoes, Hogan, Obama, Coogi,

Bape Star, Adicolor, Ice Cream,Jordan1--Jordan24,Clear Jordan, Jordan

Fusion, AJF, Jordan Flight 45,UGG Boots, Etc.

Other Products:
1. Bags/Purses :
Coach, Chanel, LV, DG, Burberry, Dior, Ed Hardy, Christian, Audigier

(CA), Fendi, Guess, Gucci, Prada, Miumiu, Versace,Juicy, Chole, Tous,

Cadillac, a,Etc.

2. Caps Hats:
ED Hardy, Smet, Coogi, New Era, SF, Bape, AFF, CA, Ke, Etc.

3. T-Shirts:
ED Hardy, Affliction, Christian, Audigier(CA), A&F, Lacoste, Armani,

Coogi, D&G, G-Star, Evisu, Ad, Polo, Versace, Bape, Rockwear, Sinful,

Smet, Gucci, Etc.

4. Hoody/Jacket/Coat:
Affliction, A&F, Blac Label, Bape, BBC, Christian Audigier(CA),
Coogi,

Crystal Rock,CLH,10Deep,D&G,EDHardy,Ecko,Evisu,GGG,Gucci,G-Star,Juicy

,Kidrobot, Kappa,
Lacoste, LRG,NY, Polo, Sinful, True Religion, Versace,Adicolor,

Armani, Burberry, LV,NF, Prada,
Spider, Etc.

5. Jeans&Pants:
A&F, True Religion, LRG, Rock, Coogi, D&G,ED Hardy, Christan
Audigier,

Red Monkey, Affliction, Artful Dodger, Armani, G-Star, Seven,

Dsquared, Ect.

6. jerseys
authentic NFL jerseys, MLB jerseys, NBA jerseys, NHL jerseys NCAA

jerseys.

7. Sunglasses:

Armani,Coach,Dior,EDHardy,Versace,LV,Rp,Fendi,Burberry,Cartier,Chanel,

Dg,Gucci,Prada,Etc.

8.belts

AAA belt:
Armani belt AAA,Boss belt AAA,D&G belt AAA,ED Hardy belt AAA,Gucci

belt AAA,LV belt AAA,Versace belt AAA,Other belt AAA,

Normal belt:
Armani belt,Bape belt,Boss belt,Burberry belt,Chanel belt,D&G belt,
Diesel belt,DSQuard belt,ED CA belt,Gucci belt,Hermes belt,Juicy
belt,
LV belt,Versace belt,Other belt

Website: http://www.jialiuonline.com

Phone number :86-791-8327716

==============================================================================
TOPIC: Our company deals in brand name hoodies,and famous brands like
http://groups.google.com/group/sci.electronics.repair/t/583dfb409e5e178e?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Oct 14 2010 7:55 pm
From: GUCCI SHOES

Our company deals in brand name hoodies,and famous brands like :ED ed-
hardy, CA christian-audigier,blac-label,polo,parish,10deep,Christian-
Audigier,Artful-Dodger,LRG,Gino-Green-
Global,CLH,,kidrobot,coogi,bape,evisu,bbc,akhoody,adicolor,afflirtion,aff,sinful
and so on. We update new styles on our website every day. Welcome to
keep concerning on our new styles.

Our business is successfully expanded to United States, Canada, United
Kingdom, Italy, Germany, Brazil etc. Meanwhile, we have set up long-
term and closed cooperation with many manufacturers and factories. Ws
believe that top quality of products, high reputation, excellent
service and professionalism are those factors that used to compete
with others.

We can not only provide the top quality products, but we also assure
you the best price in China on the basis of equal condition.

We sincerely wish to cooperate with you for mutual benefits. We will
be your first choice of suppliers for TOP quality products!

Please feel free to contact us.

Website:http://www.supertradeonline06.com/

Tel：86-791-8327716

==============================================================================
TOPIC: Dr. Jamie Sands Video - LA Dentist
http://groups.google.com/group/sci.electronics.repair/t/4961677967551c3c?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Oct 14 2010 10:32 pm
From: jennifer <123cosmeticdentist@gmail.com>

http://www.studiocitycosmeticdentist.com/video-13.php -- Los Angeles
Dentist Dr Jamie Sands, DDS, of TLCs Ten Years Younger explains .
123people refers to video content from services such as Youtube

==============================================================================
TOPIC: usb-parallel adapter for I/O
http://groups.google.com/group/sci.electronics.repair/t/3ff6a0239a413d87?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Oct 14 2010 11:53 pm
From: Chris Johnson

I have spent a few days hacking on a usb-parallel adapter based on a
Prolific pl2305 chip trying to get a bit-bang 8 bit output device for
linux... I'm very very close but I'm stuck. Its turned into more of a
puzzle than it has a useful exercise but I'm determined to get it
working.

Here is what I have figured out about the adapter. Its only made to
talk with printers so it requires handshaking. When you hook it up to
the USB port, it shows up as /dev/usblp0. echoing a character to /
dev/usblp0 always displays '00010000' on D7-D0 respectively.. thats
a DLE(data link escape character).. some research told me that this
is the token marking the beginning of the stream. A little reading
and toying around and I found that once I get the DLE, if I ground
[ACK] and [BUSY] my data will appear on D0-D7... bingo... but once I
get my data I'm stuck and can't send any more data.. which is ok...
I tried permanently grounding [ACK] and [BUSY] but it just freezes the
adapter on init.. this thing is gonna take a real circuit

So first I found/hacked a small program to send a soft reset to the
device... this resets my data lines when they are set... works like
a charm

Circuit #1 -- first success
There seems to be suffucient internal current limiting in the device
to protect everything... I just need a way to momentarily ground
[ACK] and [BUSY]. I used a 2n3904 transistor with base tied to [D4]
(only high bit in DLE)... [ACK] and [BUSY] tied to collector, and
ground tied to emitter... reset became ineffective and I could not
connect to the USB port with the transistor installed... but once the
hardware was past init and reset I could install the transistor and
send a byte... and then bingo... my data appeared on the data lines.

circuit #2 - first working circuit
I figured that maybe someplace in init and reset there was a momentary
state that tested the status lines or something and my transistor was
screwing this up... I needed a delay to get past this. so I left the
emitter and collector parts of my last circuit alone and modified the
base... I put a 1M ohm resistor in series with the base and a 100uf
cap from base to ground... it worked... but the trigger was looong
with that huge RC value and I got alot of inconsistent behavior with
the reset. so I started shrinking the C value until the device didn't
work... 10uf was the lowest I could go and this put my delay under a
second This is a buggy but useful circut for turning on lamps or
fans or something... but not for anything useful. I want more...

Circuit #3 - major improvement.. but still way too slow
Someone suggested that the data lines might not be going under .7v so
I should put a diode in series with the base... so I did... in fact
I put 2... cleaned up all of my inconsistent reset problems.... so I
started lowering the resistor value until the circuit stopped
working... well... i completely removed the resistor and the circuit
still works... and you can still see DLE flash momentarily before the
data arrives(I have LED's on the data lines)... my delay doesn't seem
to want to go away... I want this to go much faster... I tried
lowering the cap value but it won't go any lower without causing
problems with init and reset.

so... does anyone have any idea what I can do to speed up the circuit
and still have it work?

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

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 - 15 new messages in 9 topics - digest

No Response to "sci.electronics.repair - 15 new messages in 9 topics - digest"

Post a Comment

Blog Roll

Blog Archive