Today's Message Index:
----------------------
1. 01:53 AM - Alternators Basics: Regulators & OV ()
2. 03:43 AM - cannon plugs (bob noffs)
3. 05:13 AM - Re: cannon plugs (Robert L. Nuckolls, III)
4. 05:16 AM - Re:Batt charger (Robert L. Nuckolls, III)
5. 05:25 AM - Re: Reforming capacitors in strobe supply (Robert L. Nuckolls, III)
6. 05:58 AM - Re: Recommended chargers for Odyssey batteries (John Huft)
7. 06:26 AM - Trim box(es) needed. (Eric M. Jones)
8. 06:26 AM - Re: David Clark ENC connector (Mike)
9. 06:49 AM - Re: Recommended chargers for Odyssey (rd2@evenlink.com.batteries.version=3.0.3)
10. 07:19 AM - Re: Nav coax and strobe wiring in same (Robert L. Nuckolls, III)
11. 07:21 AM - Re: AeroElectric-List Digest: 18 Msgs - 11/06/05 (Ernest Christley)
12. 07:22 AM - Re: IR Alternator post mortem...Kinda (Robert L. Nuckolls, III)
13. 08:26 AM - Re: Recommended chargers for Odyssey batteries (Richard Tasker)
14. 09:20 AM - Black box info (Earl_Schroeder)
15. 12:04 PM - Re: Recommended chargers for Odyssey (rd2@evenlink.com.batteries.version=3.0.3)
16. 12:07 PM - fuse sizing (Erich_Weaver@URSCorp.com)
17. 12:35 PM - Re:Recommended chargers for Odyssey batteries (Robert L. Nuckolls, III)
18. 01:03 PM - Re: Pampering your electrolytics (Robert L. Nuckolls, III)
19. 02:19 PM - [ Mark & Lisa Sletten ] : New Email List Photo Share Available! (Email List Photo Shares)
20. 06:36 PM - Shunts or Halls (Bill Schlatterer)
21. 07:19 PM - Re: fuse sizing (Robert L. Nuckolls, III)
22. 07:45 PM - Off line for a few days. (Robert L. Nuckolls, III)
Message 1
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Subject: | Alternators Basics: Regulators & OV |
--> AeroElectric-List message posted by: <gmcjetpilot@yahoo.com>
Alternator Basics
Here are some :
The two links below give a good overall explanation of alternators, for
more detail info, see the interesting links below, many with interactive
animation:
http://1url.org/go/1paz3i
http://www.alternatorparts.com/understanding_alternators.htm
(Details and descriptions above are not applicable to all alternators, but
give a good explanation of the basics. Variations in voltage regulators,
warning light functions and diode-trio described, for example are not
applicable to newer alternators like a ND alternator with an internal VR,
described below.)
PHYSICS OF ALTERNATORS (cool ANIMATION!)
Magnetic fields
http://1url.org/go/12fg
http://micro.magnet.fsu.edu/electromag/java/compass/
http://www.walter-fendt.de/ph11e/lorentzforce.htm
DC GEN AND ALTERNATOR, WHAT'S THE DIFF?
Basic DC generator/motor: Notice the split in the slip ring. This
is called the commutator. (basic magnetic induction)
http://sun.ylojarvi.fi/java/pos/moottori.htm
http://micro.magnet.fsu.edu/electromag/java/generator/dc.html
Commutator: A commutator is an electrical switch that periodically
reverses the current in an electric motor or electrical generator.
It enables a motor to run on, and a generator to produce a direct
current (or continuous current) instead of an alternating current.
Slip ring: A slip ring consists of a conductive circle or band
mounted on a shaft and insulated from it. Electrical connections
from the rotating part of the system (such as the rotor of a
generator) are made to the ring. Fixed contacts or brushes run in
contact with the ring, transferring electrical power or signals to
the exterior, non-rotating part of the system.
AC Generator, single phase, notice unlike DC the brushes run on two
slip rings continuously vs. a DC gen where the commutator interrupts
the bushes contact.
Examples of single phase AC:
http://www.walter-fendt.de/ph11e/generator_e.htm
http://micro.magnet.fsu.edu/electromag/java/generator/ac.html
http://sun.ylojarvi.fi/java/pos/tasagene.htm
(Keep in mind we *tap* the power from the stator or the non-moving
part shown as N-S magnets in above examples. Our stators are wire
windings or coils in the alternator housing in an iron frame. Also we have
3 phases or 3 electrically separate windings to produce three phases of
AC (see below). (Why 3-phases? it is more efficient and a good trade
off.) The rotating part shown in the examples above is shown connected
to a meter. This is called the rotor in alternators. The rotor is wire wound
on iron poles on a shaft with slip rings. When the rotor is spun inside the
stator and a current is supplied to the rotor thru the slip rings, and a
magnetic FIELD is produced. This produced magnetic field induces
(induction) current in the stator coils. By varying the speed of rotation
and voltage into the rotor coils (FIELD) we vary the alternator output.
Since the voltage going to the rotor is thru wires and this produces the
magnetic FIELD, we call one of these wires a FIELD WIRE. The
field wire runs from the VR to the rotor slip ring. In an internal VR
alternator the field wire is internal. We don't see it. Using an external
VR you need to run the field wire from the regulator to the alternator.
The VOLTAGE regulator varies the voltage going to the rotor (FIELD)
to produce the proper out put voltage in the stator windings. There are
two TYPES of voltage regulators or ways to vary the field. One way
is to ground one side of the rotor to ground and vary the positive side.
This is called a type B regulator. The other type an A type regulator
which varies the ground of the rotor (FIELD) while the other side is
connected to a constant +12 V source.)
The magic is when the alternator spun at different RPM's, it changes
the frequency (RPM / 60) and amplitude (voltage) of the AC output but
the DC output voltage remains the same, even as the power demand
of the alternator output varies. The voltage regulator varies the FIELD
to maintain a constant DC output voltage!! Cool. However how do we
get from 3-phase AC power to DC. As long as the voltage regulator
maintains the voltage, we don't care about the AC frequency since we
are going to turn it into DC. Regulators discussed below.
To turn AC to DC to get a steady DC voltage out of the alternator
we run the AC thru a RECTIFIER. There is a limit to how slow we can
turn the alternator to get power. For some ND alternators the no load
(0 amps) output at 14.5 volts is 1700 RPMs. To get useful power we
need about 3000 RPM and 5000 RPM to get the rated pwr (volt-amps)
of the alternator. This varies from alternator to alternator and design. The
bigger size or diameter of the alternator or more windings, the slower
you need to turn it to make power. Rectifiers discussed below.
ALTERNATOR STATOR
http://www.k-wz.de/physik/threephasegenerator.html
(The above link is more representative of what we have going on inside
an alternator: The rotating magnet shown represents the ROTOR, but
the ROTOR in an alternator is NOT a fixed magnet as shown in the
illustration. The alternator rotor is a wire wound electromagnet. We
vary the rotor's magnetic strength by varying the voltage in it's coils.
The stator winding develops voltage and current begins to flow from the
induced magnetic field of the rotor. The term FIELD wire comes from
the wire providing the rotor voltage to produce the magnetic FIELD. The
greater the rotor (field) voltage the greater the higher the output. If the rotor
RPM is low you can adjust the field (higher voltage) to maintain the same
output as you might have at high RPM and vise a verse. Field voltage is
highest when RPM is low and power demand is high. The STATOR has
three leads, one for each phase and one neutral.)
(Notice: If you play around with the voltage and frequency in the
animations links above, the output changes. This is where the rotor, field
voltage and voltage regulator comes in to produce a constant voltage at
the output.)
HOW DO WE GET DC from AC?
(Well we showed a DC generator can produce DC current with out
a rectifier. It requires a commutator in the slip rings of the DC generator.
With an alternator we produce AC first, than rectify it to DC with a
RECTIFIER or DC BRIDGE. The rectifier or bridge is just an arrangement
of DIODES. Diodes are one way valves, allowing current in one direction
only.)
AC to DC
Rectifier or DC Bridge:
http://en.wikipedia.org/wiki/Rectifier
http://www.allaboutcircuits.com/vol_3/chpt_3/4.html
VOLTAGE REGULATOR
Now how do we control the field voltage to the field field windings
in the rotor? Voltage regulator? We know from above the alternator
operates at different RPMs and with out a regulator to control the
FIELD voltage the output voltage would change with RPM. Note:
at LOW RPMs the field current must be highest, which is harder
for the alternator to provide the power. With in reason alternators
like RPM. I think 8000 RPM is a good top end limit for the small
ND alternators, 9000rpm continuous is starting to push it, in my
opinion. If you are running the larger of the two Lycoming fly wheel
pulleys ( 9.5" vs. 7.5" dia), I would run the larger ND pulley. ND
pulleys come as small as 2.5" dia to approx 2.9". If you have a big
fly wheel pulley consider the larger alternator pulley with in reason,
3" dia on the alternator is plenty.
With the exception of shunt regulators, all voltage regulators operate
by comparing the actual output voltage to some internal fixed
reference voltage. In some simple VR's this is just a zener diode.
In other VR's there is a control voltage reference in an IC chip. Any
difference is amplified and used to control the regulation element.
This forms a negative feedback servo control loop. If the output voltage
is too low, the regulation element is commanded to produce a higher
voltage. If the output voltage is too high, the regulation element is
commanded to produce a lower voltage. In this way, the output
voltage is held roughly constant. The control loop must be carefully
designed to produce the desired trade-off between stability and
speed of response.
General description of Voltage regulators
http://en.wikipedia.org/wiki/Linear_regulator
http://en.wikipedia.org/wiki/Alternator#Theory_of_operation
Here are some voltage regulator designs (home made):
http://www.satcure-focus.com/tutor/page5.htm
http://www.hazmat.com/~mjb/candm/regulator.html
http://homepage.sunrise.ch/mysunrise/joerg.hau/mot/voltreg.htm
(Note: the basic voltage regulator shown above are early (70's) designs
made with a few discreet components. VR's with IC chips do much
more than just regulate voltage, described below.)
Here is an example of a external solid state VR (about $80):
http://www.transpo.de/cgi-win/product.exe?V1200
A Modern INTERNAL Voltage regulator
http://1url.org/go/1gx7qm
(Note: take a good look at above LINK, page 2 and this link of
a common linear VR design
http://www.hazmat.com/~mjb/candm/regulator.html
Notice: the schematics of a modern internal voltage regulator above.
There are 100's of transistors in this IC chip that you could never get
into a small enough package, using discreet parts to install directly
in the alternator. The simple VR above has about 17 components.
Each box or triangle in the diagram (page 2) of a interanl IC chip VR
may represent 3, 20 or a 100 equivalent transistors. A simple VR
can only regulated voltage; that is it. Notice some of the functions
of a I-VR below:
Over voltage detector
Thermal Limit detector
Current limit detector
Lamp driver circuit
Internal V regulator Bias current regulator
Gate polling circuit (of transistor, rotor short protection)
Source polling circuit (of transistor)
Band Gap reference generator
Digital Duty cycle generator
Ignition delay circuit
http://1url.org/go/1vy9p
(Note: This IC chip above is similar to the IC VR in the ND alternator.
To be clear the functions of modern VR's internal are way advance of
a simple voltage regulator with a few transistors, diodes, resistors and
a capacitor or two, used in the past. However many new solid state
external regulators are not much more than $5 worth of parts. These
devices have no OV protection or a OV device grafted on. Since an
internal VR is on the alternator, has the OV protection integrated, it
controls better than if mounted 4 feet away. The only down side is
heat. This is why I-VR need to mounted on an alternator with good
cooling fans (dual internal fans) and not close to external heat source.
For our aircraft, the air blast tube is critical to reliable operations.
The max ambient Temp is about 250F, but you want to be below this.
Radiant heat from exhaust pipes a foot away may be over 1000F and
can heat the back of the alternator up. ND alternators have a heat
shield and heat sink for reliable operations, but the builder should
consider everything to mitigate outside heat sources.)
Old VR's and VR's based on old 2-transistor designs have no over-voltage
protection and thus required OV module add-ons. These are no longer
needed with modern regulators with integrated OV protection and
solid-state switching.
DO NOT USE A CROW BAR or OVER VOLTAGE RELAY (contactor)
on the B-lead of a ND alternator with a I-VR. Nippon Denso says you
MUST NEVER operate the alternator with out the battery, and you must
NEVER ground or (poorly) wire the B-LEAD causing an arcing. THE
CROW BAR DOES ALL THESE (not good) THINGS. All these things
(short/arcs) should not happen and are easy to avoid with good wiring
installation. There is no controversy. The crow bar works great with
simple external VR's of the 2-transistor type but not with the IC chips
in alternators with internal VR's. If you choose to use a crow bar on an
internally regulated alternator assure that there will be no faults and
nuisance trips.
Specific to ND alternators design:
http://www.autoshop101.com/forms/h8.pdf
http://www.autoshop101.com/forms/alt_bwoh.pdf
http://www.autoshop101.com/trainmodules/alternator/alt101.html
This link is of good overall general interest
http://www.bcae1.com/charging.htm
(READ THE WARNING 2/3rds OF THE WAY DOWN!!)
George
---------------------------------
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--> AeroElectric-List message posted by: "bob noffs" <icubob@newnorth.net>
hi all,
i checked out the web sites for cannon plugs which were supplied by readers of
this site. even the 90 deg cannon will not give me clearance between my turn
coor. and my fuel tank. soooooo i plan to use the actual part of my plug that
makes the connection to my turn coor. and roll my own. i will form a 90 deg bend
with a combo of a drinking straw, 60 sec epoxy, shrink tube, and hot glue.
the hot glue will be used to encapsulate the wires and pins in the area where
i might have to disassemble someday. epoxy will capture the wires in the rest
of the straw. and of course to top it all off, shrink tubing where the wire exits
the straw. i guess i have improvised more than this before! thanks for the
input.
bob noffs
Message 3
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Subject: | Re: cannon plugs |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 05:40 AM 11/8/2005 -0600, you wrote:
>--> AeroElectric-List message posted by: "bob noffs" <icubob@newnorth.net>
>
> hi all,
> i checked out the web sites for cannon plugs which were supplied by
> readers of this site. even the 90 deg cannon will not give me clearance
> between my turn coor. and my fuel tank. soooooo i plan to use the actual
> part of my plug that makes the connection to my turn coor. and roll my
> own. i will form a 90 deg bend with a combo of a drinking straw, 60 sec
> epoxy, shrink tube, and hot glue. the hot glue will be used to
> encapsulate the wires and pins in the area where i might have to
> disassemble someday. epoxy will capture the wires in the rest of the
> straw. and of course to top it all off, shrink tubing where the wire
> exits the straw. i guess i have improvised more than this before! thanks
> for the input.
That's a LOT of work to strain-relief two wires. Consider simply stripping
the backshell off a straight connector leaving only the threaded
retainer ring.
Install lead wires in solder cups, cover each joint with a couple layers of
heat-shrink and truck on. Your connections are probably going to last the
lifetime of the airplane. If you want a little extra 'insurance', build
a masking tape potting form around the wire-end of the connector and pour
some epoxy in to a depth of perhaps 1/2".
Bob . . .
Message 4
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--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 11:10 AM 11/7/2005 -0700, you wrote:
>--> AeroElectric-List message posted by: Paul Wilson <pwmac@sisna.com>
>
>FYI,
> My Schumacher 1562A wont charge a low battery. It goes into overload and
>shuts off (red light on). The drill is up unplug it for 5 seconds to reset
>it. I finally put the flooded cell car battery on a 2 amp charger all day
>then put the 1562A on and it worked without a overload.
Sounds like they've included some circuitry intended to
prevent the situation we've been discussing on the Deltran
BT Jr.
> I left the thing
>for a month and when I got back the green light was on indicating voltage
>above 13.2. Nice to have a fully charged battery after it sitts a while.
Have you ever put a voltmeter on the battery to see what you get
after a week or so?
Bob . . .
Message 5
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Subject: | Re: Reforming capacitors in strobe supply |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 09:00 AM 11/7/2005 -0800, you wrote:
>--> AeroElectric-List message posted by: "John Burnaby" <jonlaury@impulse.net>
>
>Could one not connect the appropriate # of D cells in series for a poor
>man's variac for a one time solution?
>
>I too have a Whelen system that will need some rejuvenation from prolonged
>storage.
Sure.
First, I'm skeptical of Whelen's assertions that this
is a necessary or even a very useful thing to do with
modern electrolytic capacitors. They're much better
than the devices that went into Whelen's first products
40+ years ago. Effects internal to the capacitor that
drive a need for 'reforming' a long-stored capacitor have
all but disappeared.
If you're agonizing over it, get a 6v lantern battery
from Wallmart (About $5 with a flashlight) and hook this
up first. Let it run the battery down totally. Then hook
the supply up to a 12 lead acid battery on the bench
with no charger on it. Leave this running for a few hours.
I'm pretty sure this is insurance against an invasion of
pink elephants but it represents a more doable exercise
for those who don't have a variable bench supply.
Bob . . .
Message 6
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Subject: | Re: Recommended chargers for Odyssey batteries |
version=3.0.3
--> AeroElectric-List message posted by: John Huft <aflyer@lazy8.net>
Well, back to the original question.
The reason we can't use a Deltran Battery Tender to recharge a dead
battery is that it won't turn on. It, and no doubt some other brands of
"Battery Maintainers" are specifically designed to hold a charge on a
mostly charged up battery, not to recharge dead batteries. This saved
some amount of money in manufacturing cost.
So, we will have to think about what we want to accomplish when we buy a
battery charger, or battery maintainer. Going from the lead from
Rumen, this one looks like a winner from BatteryMart, for an extra $5,
even claims to be approved by Odyssey...
http://www.batterymart.com/battery.mv?p=ACC-1206WB
Otherwise, I am sure Bob is correct, that as long as a charger's output
exceeds the battery's leakage rate, it will eventually charge the battery.
John
Robert L. Nuckolls, III wrote:
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
>
> Good morning,
>
> One of my clients has cited your webpage at . . .
>
> http://www.odysseybatteries.com/charging.htm
>
> . . . where you state:
>
> "There is another class of chargers that is designed
> specifically to maintain the battery in a high state
> of charge. These chargers, such as the 1.25 amp
> Battery Tender from Deltran are not capable of charging
> a deeply discharged ODYSSEY battery. This is due to
> the fact that these chargers have very low output power.
> They should only be used either to continuously
> compensate for parasitic losses or to maintain a trickle
> charge on a fully charged stored battery."
>
> I've searched my sources on lead-acid battery technologies
> and found no references to charging efficiencies
> base on charging rate. While the small chargers cited
> are limited in their power output, my present sense is that
> this only extends the time required for a given battery
> to reach full charge.
>
> Your webpage implies that an Odyssey battery can only
> be efficiently charged if the re-charge time is on the
> order of 2 hours.
>
> Can you enlighten me on the supporting physics of
> your assertions? I do a lot of work with batteries
> in the aircraft industries and I'm often called upon to
> offer advice on battery operation and maintenance.
> If there's an important point of physics in battery operation
> that I'm unaware of, I'd be very pleased if you could
> point me in the right direction for acquiring that
> knowledge.
>
> Regards,
>
> Bob Nuckolls
> AeroElectric Connection
> Wichita, KS
>
>
>
>
>
>
>
>
>
Message 7
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Subject: | Trim box(es) needed. |
--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
I'm building a test fixture and need an MAC or RAC trim box. Beaten up is fine.
Fixable is okay. Free is good but cheap is okay.
Let me know offline.
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
(508) 764-2072
Message 8
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Subject: | David Clark ENC connector |
--> AeroElectric-List message posted by: "Mike" <mlas@cox.net>
I don't! But I am wondering what you are trying to do? They do make an
adapter to the Bose type plug in from that 10 pin connector. Then you
go to a Bose socket, makes for a very nice install....
Mike Larkin
Lancair Legacy
Kitfox IV
TS-11
A-320
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Dave
Durakovich
Subject: AeroElectric-List: David Clark ENC connector
--> AeroElectric-List message posted by: Dave Durakovich
<ddurakovich@yahoo.com>
Anyone have a part number on the quick connector that David Clark uses
on their ENC headsets (ie; H20-10X) ? It's a 10 pin mini circular plug
with a quick connect (air hose type pull back) feature.
Thanks,
Dave Durakovich
Message 9
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Subject: | Re: Recommended chargers for Odyssey |
batteries version=3.0.3
--> AeroElectric-List message posted by: rd2@evenlink.com batteries version=3.0.3
Tx for the link, John.
This looks very much like the Soneil charger, the numbers look like Soneil
product numbers, in fact at the end of the description, it reads "Soneil
replacement". I called batterymart and a rep stated that this product is
made by Soneil. I am waiting for a confirmation from Soneil and details on
the charging cycles.
Rumen
do not archive
_____________________Original message __________________________
(received from John Huft; Date: 06:59 AM 11/8/2005 -0700)
--> AeroElectric-List message posted by: John Huft <aflyer@lazy8.net>
Well, back to the original question.
The reason we can't use a Deltran Battery Tender to recharge a dead
battery is that it won't turn on. It, and no doubt some other brands of
"Battery Maintainers" are specifically designed to hold a charge on a
mostly charged up battery, not to recharge dead batteries. This saved
some amount of money in manufacturing cost.
So, we will have to think about what we want to accomplish when we buy a
battery charger, or battery maintainer. Going from the lead from
Rumen, this one looks like a winner from BatteryMart, for an extra $5,
even claims to be approved by Odyssey...
http://www.batterymart.com/battery.mv?p=ACC-1206WB
Otherwise, I am sure Bob is correct, that as long as a charger's output
exceeds the battery's leakage rate, it will eventually charge the battery.
John
Robert L. Nuckolls, III wrote:
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<nuckollsr@cox.net>
>
> Good morning,
>
> One of my clients has cited your webpage at . . .
>
> http://www.odysseybatteries.com/charging.htm
>
> . . . where you state:
>
> "There is another class of chargers that is designed
> specifically to maintain the battery in a high state
> of charge. These chargers, such as the 1.25 amp
> Battery Tender from Deltran are not capable of charging
> a deeply discharged ODYSSEY battery. This is due to
> the fact that these chargers have very low output power.
> They should only be used either to continuously
> compensate for parasitic losses or to maintain a trickle
> charge on a fully charged stored battery."
>
> I've searched my sources on lead-acid battery technologies
> and found no references to charging efficiencies
> base on charging rate. While the small chargers cited
> are limited in their power output, my present sense is that
> this only extends the time required for a given battery
> to reach full charge.
>
> Your webpage implies that an Odyssey battery can only
> be efficiently charged if the re-charge time is on the
> order of 2 hours.
>
> Can you enlighten me on the supporting physics of
> your assertions? I do a lot of work with batteries
> in the aircraft industries and I'm often called upon to
> offer advice on battery operation and maintenance.
> If there's an important point of physics in battery operation
> that I'm unaware of, I'd be very pleased if you could
> point me in the right direction for acquiring that
> knowledge.
>
> Regards,
>
> Bob Nuckolls
> AeroElectric Connection
> Wichita, KS
>
>
>
>
>
>
>
>
>
--
Checked by AVG Free Edition.
Message 10
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Subject: | Re: Nav coax and strobe wiring in same |
conduit
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
conduit
At 06:26 PM 11/7/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: <bbradburry@allvantage.com>
>
>My Legacy has a nav antenna in the wing tip. The position and strobe lights
>are also there and there is only one conduit to bring the wireing into the
>fuselage. Is there going to be a problem with this setup and should I do
>something special to these cables? The nav antenna will be connected with
>crimp ring connectors. I know I should keep these short. Anything else?
Many folks have installed the system you've described with
satisfactory results.
Bob . . .
Message 11
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Subject: | Re: AeroElectric-List Digest: 18 Msgs - 11/06/05 |
--> AeroElectric-List message posted by: Ernest Christley <echristley@nc.rr.com>
My strobe power
> supply has been setting for a few years. As such, Whelen's tech strongly
> suggested that I connect it to a variable voltage device (Isn't that a
> variac?), set it at 3 Volts for 15 minutes, 6 Volts for 15 minutes, 9 Volts
> for 15 minutes & finally 12 Volts. As a side question out of curiosity,
> what does this do?
Tinne,
I just get the list as a digest as I finish up my airframe, but I have some interesting
experience that illustrates exactly what this does.
I worked as an electronics test technician at AT&T for several years, doing 'bed
of nails' testing. A circuit board was placed on a fixture and then was sucked
down onto a set of probes (metal pins) by a vacuum. A computer then ran all
sorts of current and voltage signals through the circuit.
You have to understand that electrolytic caps are very closely related to batterys.
Basically, they are rolled up foil with a layer of acid between. If a current
has never been run through them (or if they've been setting for a long
time), the acid will not have created a complete oxide layer on one or both sides
of the foil. The capacitors job is to hold electrons like a bucket, and the
oxide layer is the container. Without that layer, the electrons run straight
through, which is usually called a short circuit. On that initial energization,
you have an inrush current that not only must fill the capacitor and form
the oxide layer, but must also energize the short circuit path. The capacitor
has to be able to withstand all the initial current.
One device we tested was a small circuit that was full of little electrolytic capacitors.
Very soon after the product went into production, they switched to
a cheaper supplier for the electrolytics. After the switch, about every 4th
or 5th time the test was run a few would make a small explosion and burn. The
test engineer modified the test to ramp up the voltage slower, but I still had
to take to wearing a pair of the glove that I stole from the guy that maintained
the wave solder machine. The parts just could not handle the inrush.
Whelen wants you to be nice to your capacitors, I suspect.
--
,|"|"|, |
----===<{{(oQo)}}>===---- Dyke Delta |
o| d |o www.ernest.isa-geek.org |
Message 12
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Subject: | Re: IR Alternator post mortem...Kinda |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 09:25 AM 11/7/2005 -0800, you wrote:
>--> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)"
><frank.hinde@hp.com>
>
> Bob thankyou for your kind offer to send you my IR alt that was
>behaving erratically. Suspecting it was just the brushes I thought it
>worth opening up the case to see if it was something simple.
>
>I found that the oil leak from the sump filler cap had been lubricating
>the back of my alternator and the slip ring brush interface had a nice
>greasy goop made of oil and brush material covering the slip rings.
>Definatly looks like this has been lifting the brushes off the slip
>rings.
>
>The inside of the alt has a lot of this stuff and the first thing I will
>do is clean it up and reinstall it on the airplane, having found an
>assignable cause.
You may want to replace the brushes. These are porous and will
have absorbed some of the contaminating oil.
>So the easy question is what sort of solvent should I use? I have some
>acetone but I'm concerned I mught remove shellac from the windings and
>or melt the plastic parts.
Use a mild solvent. Paint thinner, filling station solvent, charcoal
lighter etc. I keep spray cans of carburetor cleaner for board cleaning
which is basically lacquer thinner in a spray can. Acetone is very
aggressive and will attack many plastics.
Bob . . .
Message 13
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|
Subject: | Re: Recommended chargers for Odyssey batteries |
version=3.0.3
--> AeroElectric-List message posted by: Richard Tasker <retasker@optonline.net>
FWIW... I have one of these and it does say Soneil on the data label..
I have used it to top off my Odyssey 625 and it seems to work fine. It
also says it will start a charge as low as 0.5V.
Dick Tasker
rd2@evenlink.com.batteries.version=3.0.3 wrote:
>--> AeroElectric-List message posted by: rd2@evenlink.com batteries version=3.0.3
>
>Tx for the link, John.
>This looks very much like the Soneil charger, the numbers look like Soneil
>product numbers, in fact at the end of the description, it reads "Soneil
>replacement". I called batterymart and a rep stated that this product is
>made by Soneil. I am waiting for a confirmation from Soneil and details on
>the charging cycles.
>
>Rumen
>do not archive
>
>
>_____________________Original message __________________________
> (received from John Huft; Date: 06:59 AM 11/8/2005 -0700)
>
>--> AeroElectric-List message posted by: John Huft <aflyer@lazy8.net>
>
>Well, back to the original question.
>
>The reason we can't use a Deltran Battery Tender to recharge a dead
>battery is that it won't turn on. It, and no doubt some other brands of
>"Battery Maintainers" are specifically designed to hold a charge on a
>mostly charged up battery, not to recharge dead batteries. This saved
>some amount of money in manufacturing cost.
>
>So, we will have to think about what we want to accomplish when we buy a
> battery charger, or battery maintainer. Going from the lead from
>Rumen, this one looks like a winner from BatteryMart, for an extra $5,
>even claims to be approved by Odyssey...
>
>http://www.batterymart.com/battery.mv?p=ACC-1206WB
>
>Otherwise, I am sure Bob is correct, that as long as a charger's output
>exceeds the battery's leakage rate, it will eventually charge the battery.
>
>John
>
>
>Robert L. Nuckolls, III wrote:
>
>
>>--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
>>
>>
><nuckollsr@cox.net>
>
>
>> Good morning,
>>
>> One of my clients has cited your webpage at . . .
>>
>>http://www.odysseybatteries.com/charging.htm
>>
>> . . . where you state:
>>
>>"There is another class of chargers that is designed
>>specifically to maintain the battery in a high state
>>of charge. These chargers, such as the 1.25 amp
>>Battery Tender from Deltran are not capable of charging
>>a deeply discharged ODYSSEY battery. This is due to
>>the fact that these chargers have very low output power.
>>They should only be used either to continuously
>>compensate for parasitic losses or to maintain a trickle
>>charge on a fully charged stored battery."
>>
>> I've searched my sources on lead-acid battery technologies
>> and found no references to charging efficiencies
>> base on charging rate. While the small chargers cited
>> are limited in their power output, my present sense is that
>> this only extends the time required for a given battery
>> to reach full charge.
>>
>> Your webpage implies that an Odyssey battery can only
>> be efficiently charged if the re-charge time is on the
>> order of 2 hours.
>>
>> Can you enlighten me on the supporting physics of
>> your assertions? I do a lot of work with batteries
>> in the aircraft industries and I'm often called upon to
>> offer advice on battery operation and maintenance.
>> If there's an important point of physics in battery operation
>> that I'm unaware of, I'd be very pleased if you could
>> point me in the right direction for acquiring that
>> knowledge.
>>
>> Regards,
>>
>> Bob Nuckolls
>> AeroElectric Connection
>> Wichita, KS
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
>
>
Message 14
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|
--> AeroElectric-List message posted by: Earl_Schroeder <Earl_Schroeder@juno.com>
Black box offers 'technical' info from time to time. Here is an
example: http://tinyurl.com/ae278
You may agree or disagree.. Earl
Message 15
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|
Subject: | Re: Recommended chargers for Odyssey |
batteries version=3.0.3
--> AeroElectric-List message posted by: rd2@evenlink.com batteries version=3.0.3
Tx, Dick. Soneil just confirmed that it is their product.
Rumen
_____________________Original message __________________________
(received from Richard Tasker; Date: 11:23 AM 11/8/2005
-0500)
--> AeroElectric-List message posted by: Richard Tasker
<retasker@optonline.net>
FWIW... I have one of these and it does say Soneil on the data label..
I have used it to top off my Odyssey 625 and it seems to work fine. It
also says it will start a charge as low as 0.5V.
Dick Tasker
rd2@evenlink.com.batteries.version=3.0.3 wrote:
>--> AeroElectric-List message posted by: rd2@evenlink.com batteries
version=3.0.3
>
>Tx for the link, John.
>This looks very much like the Soneil charger, the numbers look like Soneil
>product numbers, in fact at the end of the description, it reads "Soneil
>replacement". I called batterymart and a rep stated that this product is
>made by Soneil. I am waiting for a confirmation from Soneil and details on
>the charging cycles.
>
>Rumen
>do not archive
>
>
>_____________________Original message __________________________
> (received from John Huft; Date: 06:59 AM 11/8/2005 -0700)
>
>--> AeroElectric-List message posted by: John Huft <aflyer@lazy8.net>
>
>Well, back to the original question.
>
>The reason we can't use a Deltran Battery Tender to recharge a dead
>battery is that it won't turn on. It, and no doubt some other brands of
>"Battery Maintainers" are specifically designed to hold a charge on a
>mostly charged up battery, not to recharge dead batteries. This saved
>some amount of money in manufacturing cost.
>
>So, we will have to think about what we want to accomplish when we buy a
> battery charger, or battery maintainer. Going from the lead from
>Rumen, this one looks like a winner from BatteryMart, for an extra $5,
>even claims to be approved by Odyssey...
>
>http://www.batterymart.com/battery.mv?p=ACC-1206WB
>
>Otherwise, I am sure Bob is correct, that as long as a charger's output
>exceeds the battery's leakage rate, it will eventually charge the battery.
>
>John
>
>
>Robert L. Nuckolls, III wrote:
>
>
>>--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
>>
>>
><nuckollsr@cox.net>
>
>
>> Good morning,
>>
>> One of my clients has cited your webpage at . . .
>>
>>http://www.odysseybatteries.com/charging.htm
>>
>> . . . where you state:
>>
>>"There is another class of chargers that is designed
>>specifically to maintain the battery in a high state
>>of charge. These chargers, such as the 1.25 amp
>>Battery Tender from Deltran are not capable of charging
>>a deeply discharged ODYSSEY battery. This is due to
>>the fact that these chargers have very low output power.
>>They should only be used either to continuously
>>compensate for parasitic losses or to maintain a trickle
>>charge on a fully charged stored battery."
>>
>> I've searched my sources on lead-acid battery technologies
>> and found no references to charging efficiencies
>> base on charging rate. While the small chargers cited
>> are limited in their power output, my present sense is that
>> this only extends the time required for a given battery
>> to reach full charge.
>>
>> Your webpage implies that an Odyssey battery can only
>> be efficiently charged if the re-charge time is on the
>> order of 2 hours.
>>
>> Can you enlighten me on the supporting physics of
>> your assertions? I do a lot of work with batteries
>> in the aircraft industries and I'm often called upon to
>> offer advice on battery operation and maintenance.
>> If there's an important point of physics in battery operation
>> that I'm unaware of, I'd be very pleased if you could
>> point me in the right direction for acquiring that
>> knowledge.
>>
>> Regards,
>>
>> Bob Nuckolls
>> AeroElectric Connection
>> Wichita, KS
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
>
>
--
Checked by AVG Free Edition.
Message 16
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|
11/08/2005 03:04:13 PM
--> AeroElectric-List message posted by: Erich_Weaver@URSCorp.com
OK, more basic questions from a wannabe Knuckollhead.
The AeroElectric Connection teaches that fuses have but one purpose - to
protect WIRES.
If thats true, it would stand to reason that one can simply size all fuses
by the maximum amp rating for the selected wire, per the wire table in
chapter 8.
However, perusal of the Z-diagrams shows fuse ratings that are commonly
below the capabilities of the indicated wire sizes. For e.g., I see a lot
of 3 amp or even 1 amp fuses on 22 awg wire, which has a rating of 5 amps.
Why would that be, unless we are trying to protect something other than the
wire itself? Its a small point, but all other factors being equal, I would
want to keep the number of different fuse types that I keep around to a
minimum, no?
I am tempted to resort to the commonly held view that we are really
interested in also protecting the device at the end of the wire. This
would seem to be supported by the documentation I have received from
manufacturer's for their various products. For example, the documentation
for the fuel injector booster pump I just received from Vans emphatically
states that it must be protected with a 7 amp fuse (I could be off on the
exact value - but thats beside the point). I would certainly be reluctant
to disregard the manufacturers specific instructions when wiring this thing
up, even if I got a scoff or two from the list.
Someone care to set me straight on this?
I would guess this issue has been discussed before, but I wasnt quite sure
how to fully capture the subject matter for the archive search
Erich Weaver
Message 17
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|
Subject: | Re:Recommended chargers for Odyssey batteries |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 06:59 AM 11/8/2005 -0700, you wrote:
>--> AeroElectric-List message posted by: John Huft <aflyer@lazy8.net>
>
>Well, back to the original question.
>
>The reason we can't use a Deltran Battery Tender to recharge a dead
>battery is that it won't turn on. It, and no doubt some other brands of
>"Battery Maintainers" are specifically designed to hold a charge on a
>mostly charged up battery, not to recharge dead batteries. This saved
>some amount of money in manufacturing cost.
Given your discovery of rather simplistic electronics, it's
obvious that the little Deltran product could be hard pressed
to recharge a really 'dead' battery. By definition of energy
stored, a battery that is 95% used up would be useless but
the open circuit terminal votlage would still be well above 10v
and would rise rather rapidly such that the small Deltran product
was not at-risk for smoke. I've used these chargers on all
sizes and combinations of sizes for long term recharge duty
with good results.
A battery that has been discharged to lower voltage has been
severely discharged and while you could certainly call it
'dead', it's also abused. These batteries are worthy of
special recovery and recharging consideration including a
cap check to make sure they're flight worthy.
>So, we will have to think about what we want to accomplish when we buy a
> battery charger, or battery maintainer. Going from the lead from
>Rumen, this one looks like a winner from BatteryMart, for an extra $5,
>even claims to be approved by Odyssey...
>
>http://www.batterymart.com/battery.mv?p=ACC-1206WB
>
>Otherwise, I am sure Bob is correct, that as long as a charger's output
>exceeds the battery's leakage rate, it will eventually charge the battery.
There are hundreds of capable products out there not the least
of which are off-the-shelf at Walmart. Every product on the
rack last time I checked was a smart charger and I think the
smallest was a 2A device. Obviously more robust than the
DBTJr but if pressed into a situation where it was tasked
with charging a 'loaded' battery, it might be vulnerable
to smoke as well.
Unless they're REALLY smart with current-limiting, over-temp
shutdown, over-time shutdown, etc. it's probably possible
to kill most tools when operated in the worst case corner
of its design envelope.
Bob . . .
Message 18
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|
Subject: | Re: Pampering your electrolytics |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 10:20 AM 11/8/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: Ernest Christley
><echristley@nc.rr.com>
>
>
>My strobe power
> > supply has been setting for a few years. As such, Whelen's tech strongly
> > suggested that I connect it to a variable voltage device (Isn't that a
> > variac?), set it at 3 Volts for 15 minutes, 6 Volts for 15 minutes, 9 Volts
> > for 15 minutes & finally 12 Volts. As a side question out of curiosity,
> > what does this do?
>
>Tinne,
>I just get the list as a digest as I finish up my airframe, but I have
>some interesting experience that illustrates exactly what this does.
>
>I worked as an electronics test technician at AT&T for several years,
>doing 'bed of nails' testing. A circuit board was placed on a fixture and
>then was sucked down onto a set of probes (metal pins) by a vacuum. A
>computer then ran all sorts of current and voltage signals through the circuit.
>
>You have to understand that electrolytic caps are very closely related to
>batterys. Basically, they are rolled up foil with a layer of acid
>between. If a current has never been run through them (or if they've been
>setting for a long time), the acid will not have created a complete oxide
>layer on one or both sides of the foil. The capacitors job is to hold
>electrons like a bucket, and the oxide layer is the container. Without
>that layer, the electrons run straight through, which is usually called a
>short circuit. On that initial energization, you have an inrush current
>that not only must fill the capacitor and form the oxide layer, but must
>also energize the short circuit path. The capacitor has to be able to
>withstand all the initial current.
>
>One device we tested was a small circuit that was full of little
>electrolytic capacitors. Very soon after the product went into
>production, they switched to a cheaper supplier for the
>electrolytics. After the switch, about every 4th or 5th time the test
>was run a few would make a small explosion and burn. The test engineer
>modified the test to ramp up the voltage slower, but I still had to take
>to wearing a pair of the glove that I stole from the guy that maintained
>the wave solder machine. The parts just could not handle the inrush.
On brand new boards? Amazing. New caps out of the box
should not be so limited. Whelen's original recommendations
cited strobe supplies that were in storage for long (5-10
years) periods of time and certainly didn't apply to a fresh,
out-of-the-box product.
Here's a tutorial on the innermost secrets of an electrolytic
capacitor.
http://electrochem.cwru.edu/ed/encycl/art-c04-electr-cap.htm
. . . .it even speaks to the special considerations for capacitors
use for strobes . . . but even these issues are not prevalent until
we get to flash rates on the order of 3/second. Aircraft strobes are
about 1.5/sec.
Here's an article that speaks specifically to procedures for
salvaging OLD capacitors . . .
http://www.nmr.mgh.harvard.edu/~reese/electrolytics/#reform
A quote from the article: "Electrolytics do not suffer idleness well.
They can cause big trouble when idle for long periods, needing periodic
charging to stay "formed" and maintain the oxide layer that insulates
the conducting plates."
Accurate but not very informative. The term "long" is non-quantified.
I've taken the time to re-form many an old capacitor . . . my favorite
technique is to apply rated voltage through a resistor that limits
current flow to 1 mA max. For example, a 300v cap would be charged
through a 300K resistor. I've always watched the terminal voltage
across the capacitor and NEVER had a cap take more than 10 minutes
to charge to within 90% of rated voltage (i.e. leakage less than
100 microamperes). My sense is that had I applied full voltage through
a much lower resistance that the results would not have been spectacular
or even noteworthy. I've blow up a few capacitors (very spectacular)
but in every case it was due to over-voltage or reversed polarity.
Sometimes they can be "reformed" by a slowly rising return to working
voltage (see below). Even with regular use, electrolytics fail with age by
drying out or leaking electrolyte following internal corrosion. If the
electrolytic bulges, shows obvious loss of electrolyte, or simply can't be
reformed you must replace it.
I think the term "long" means products more than 10 years old
and even then, the act of performing a re-forming ritual is of
very limited benefit.
Bob . . .
Message 19
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|
Subject: | [ Mark & Lisa Sletten ] : New Email List Photo Share |
Available!
--> AeroElectric-List message posted by: Email List Photo Shares <pictures@matronics.com>
A new Email List Photo Share is available:
Poster: Mark & Lisa Sletten <marknlisa@hometel.com>
Lists: AeroElectric-List
Subject: System Schematic
http://www.matronics.com/photoshare/marknlisa@hometel.com.11.08.2005/index.html
o Main Photo Share Index
http://www.matronics.com/photoshare
o Submitting a Photo Share
If you wish to submit a Photo Share of your own, please include the
following information along with your email message and files:
1) Email List or Lists that they are related to:
2) Your Full Name:
3) Your Email Address:
4) One line Subject description:
5) Multi-line, multi-paragraph description of topic:
6) One-line Description of each photo or file:
Email the information above and your files and photos to:
pictures@matronics.com
Message 20
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|
"Aeroelectric List" <aeroelectric-list@matronics.com>
--> AeroElectric-List message posted by: "Bill Schlatterer" <billschlatterer@sbcglobal.net>
Todd, you sent me a Hall effect sensor which I assume is for measuring
alternator amperage. I also am running a standby alt which I think means I
might need two hall sensors. Without reading the instructions, does this
mean that I don't need the alternator shunts to pick up the alt amperage?
Shunts came from B&C.
Thanks Bill S
Bill Schlatterer
501 851 0310
Maumelle, Arkansas
Message 21
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--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
At 12:04 PM 11/8/2005 -0800, you wrote:
>--> AeroElectric-List message posted by: Erich_Weaver@URSCorp.com
>
>OK, more basic questions from a wannabe Knuckollhead.
>
>The AeroElectric Connection teaches that fuses have but one purpose - to
>protect WIRES.
>
>If thats true, it would stand to reason that one can simply size all fuses
>by the maximum amp rating for the selected wire, per the wire table in
>chapter 8.
>
>However, perusal of the Z-diagrams shows fuse ratings that are commonly
>below the capabilities of the indicated wire sizes. For e.g., I see a lot
>of 3 amp or even 1 amp fuses on 22 awg wire, which has a rating of 5 amps.
>Why would that be, unless we are trying to protect something other than the
>wire itself? Its a small point, but all other factors being equal, I would
>want to keep the number of different fuse types that I keep around to a
>minimum, no?
Why? They're not expensive. You're not likely to need very many
fuses in total even if you have a lot of different sizes.
>I am tempted to resort to the commonly held view that we are really
>interested in also protecting the device at the end of the wire. This
>would seem to be supported by the documentation I have received from
>manufacturer's for their various products. For example, the documentation
>for the fuel injector booster pump I just received from Vans emphatically
>states that it must be protected with a 7 amp fuse (I could be off on the
>exact value - but thats beside the point). I would certainly be reluctant
>to disregard the manufacturers specific instructions when wiring this thing
>up, even if I got a scoff or two from the list.
>
>Someone care to set me straight on this?
>
>I would guess this issue has been discussed before, but I wasnt quite sure
>how to fully capture the subject matter for the archive search
The first priority is indeed wire protection. A second consideration
might include devices on the end of the wire especially in itty-bitty
electro-whizzies. If you have a device that runs on say 100 mA and has
an etched circuit board inside, it MIGHT be beneficial to fuse it with
a 1A fuse on a 22AWG feeder just to preclude burning a trace on the board
due to internal fault. Faulted parts are easy to replace, burned traces
more difficult if not catastrophic to the product. However, if minimum
numbers of fuse sizes is your design goal, there's not a thing wrong
with making 5A the smallest horse in the stable.
Keep in mind that NOTHING in the 'Connection is intended to recommend any
particular size wire or fuse for similar applications in your airplane.
You need to evaluate what might be significant variables both in appliance
needs along with your personal design goals. The primary intent of the
z-figures is to discuss architectures best suited to how your airplane
is equipped and how you plan to use it. The details like fuse and wire
sizes should be re-evaluated to make sure they match what you're going
to install.
Bob . . .
Message 22
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Subject: | Off line for a few days. |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
I'm packing up tools and test fixtures to go hammer on a brand new
bizjet with generator controls that barf when the HF transmitter is
keyed. If things go well, I'll be back by the weekend.
Bob . . .
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