Pete O Shea
Feb 01, 1997, 01:00 AM
<p><font size="4">February 1997: Safety considerations for electric planes</font> </p>
<p>This month I want to write about safety issues, both equipment to install in our
planes, and procedures we should follow. I'll only try to cover things that are
specific to electric-powered airplanes. General safety topics are addressed in the
AMA Safety Code, as well as by common sense. </p>
<p>There are three areas where, I believe, electrics differ significantly from
fuel-powered planes and need special attention. One is the instant-on characteristic
of electric motors, another is the capability of a motor to deliver torque and consume
power at stall, and the third is the special characteristics of a nicad battery pack that
merit consideration. </p>
<hr>
<p><font size="4">I. Electric motors can start instantly!</font> </p>
<p>You've seen it hundreds of times. The spinning, the valve-tweaking, the
fuel-priming, the glow-plug changing, the swearing.....yes, starting a glow-powered engine
is a real pain. To top it off, as soon as the plane gets to the runway, the engine dies!
Not so with electrics, of course. We're blessed with easy-starting, reliable power. But
that blessing comes at a cost, and that cost is <u>vigilance</u>. The spinning prop
attached to our motors can send you to the emergency room, but fast. Some wise
precautions to take are:
<ol>
<li>Don't connect the motor battery until you have your frequency pin (or other frequency
clearance means) and are ready to put the plane on the runway or hand-launch. </li>
<li>Don't turn on the radio system until you are ready for your flight. Turn off the
radio system as soon as possible after the flight. </li>
<li>Make sure that the throttle is set to off <u>before</u> turning on your transmitter.
Many digital speed controls have a function that won't allow the motor to turn until the
throttle stick has been in, or moved to, the low position. Don't make it a habit of
testing this function. </li>
<li>Motor-on radio checks must be done with the aid of a helper. </li>
<li>Check the leading edge and tip of your prop for molding flash, if it's not a wood prop.
Carefully sand away molding flash with fine sandpaper. </li>
</ol>
<p>Even these precautions aren't enough for high-powered planes. Any plane with the
potential to cause injury from the spinning prop needs a redundant safety system. Just
where to draw this line is debatable, but I recommend that any plane larger than speed 400
size (approximately 100 watts and above) have an arming switch. The arming switch
is, simply, a cutoff switch that goes between the battery and anything else in the plane.
The arming switch is left off until the plane is ready to taxi out to the runway (or
be hand-launched). When retrieving the plane after the flight, the arming switch is
the first thing turned off. </p>
<p>One argument against using an arming switch is that it adds a power loss to our limited
power budget. When used properly, an arming switch will not cause any noticeable
drop in system power. The simple secret to a long-lasting, low-loss arming switch is
this: NEVER SWITCH CURRENT with the arming switch. The switch should only <u>carry</u>
current. This means that you never turn the switch to "on" until the throttle is
in the low position, and similarly after the flight the switch is only turned
"off" after the throttle is again in the low position. The reason behind
this is simple: inductive loads, such as our electric motors, cause small arcs between the
metal contacts when the switch is actuated (especially on the opening, or breaking
action). The arcs cause pitting of the contacts and the formation of carbon deposits. This
makes the switch resistance go up, causing us to lose precious power in the switch. In
extreme cases, the contacts can even be welded together (I saw this more than once as a
failure analysis engineer at NASA). </p>
<p>The arming switch, when used properly, adds the critical element of redundancy against
the power system inadvertently turning on. A good arming switch for general use is
sold by Jomar and available through New Creations RC. This switch is a double-pole
rocker switch with a plastic package, and is relatively small and lightweight. Radio
Shack also carries a few automobile rocker switches that have appropriate current ratings,
but are somewhat larger. Digi-Key carries a wide selection of switches, any number
of which could be used. Try to find a switch with a current rating of 10 to 20A per pole,
which will be acceptable for sport use. </p>
<blockquote>
<p><font color="#FF0000">Cost of safety: <$5 for switch, 30 minutes or less to install</font>
</p>
<p><font color="#FF0000">Cost of accident: blood, stitches, tendon and/or nerve damage</font>
</p>
<p><font color="#FF0000">Which one is the sensible choice?</font> </p>
</blockquote>
<hr>
<p><font size="4">II. At stall, an electric motor delivers torque and draws current</font>
</p>
<p>When a fuel-powered engine stalls, or is stopped, it is dead. It does nothing, is
quiet (finally!) and produces no oily exhaust. When an electric motor is stalled by
mechanically stopping the prop, it goes into an entirely different state (assuming the
throttle is in the "on" position). The current becomes limited only by the
total resistance of the circuit - a sum of nicad internal impedance, wiring harness
resistance, speed control resistance, and motor armature resistance. The current will
be I = Vbattery / Rtotal. This total resistance is (if you've built your system well)
low. The current might well be over a hundred amps, if not more. </p>
<p>Who cares about a bit of extra current? You will, if it causes some part of your
system to overheat enough to start a fire. You'll care even more if this fire
spreads to the dry grass surrounding your flying field where your plane has crashed (ok,
maybe I'm being a bit alarmist). Your wallet will care if your motor or speed
control is smoked and unusable. </p>
<p>How do we fight this fire? By preventing it in the first place, using a
time-tested device that automatically cuts off the current when it gets dangerously high.
I'm talking about, of course, the humble fuse. Fuses are ancient devices, dating
back to the ancient Romans (well, maybe not)....ok, back to the beginnings of electric
power systems about a hundred years ago. A fuse is just a conductor of a controlled
length, thickness, and composition, which is designed to overheat and melt at a specified
current level. The melted fuse material falls away from the unmelted portion,
breaking the electrical connection and interrupting the current flow. </p>
<p>The fuse is the ultimate in safety protection - it is impossible for it to fail in an
unsafe manner. Yes, I'm an engineer, and I said "impossible". That is, a fuse
can open when not wanted (termed a "nuisance blow"), but a fuse made with the
correct element in the correct diameter CANNOT fail to clear when the specified current is
exceeded. Well, actually, if the current is extremely high (10,000 amps might do
it), a plasma can be formed inside the fuse and it will keep conducting current. For
our application, I'm going to still call that impossible (the internal resistance of our
current source, the nicad, limits the current to levels well below this). No other
current protection scheme can offer this level of protection. </p>
<p>And it only costs a buck or less. It can weigh as low as a few measly grams.
There is NO EXCUSE NOT TO USE ONE. </p>
<p>Have I convinced you yet? Ok, now let's talk about which fuse to use: </p>
<blockquote>
<p>For speed 400 systems: the Littelfuse Picofuse, available through Digi-Key
(1-800-DIGIKEY) for about a buck apiece. These are the size of a 1/4 watt resistor
and have ratings up to 15 amps. </p>
<p>For higher-powered planes: the automotive blade fuse, available at your local auto
parts dealer, K-Mart, Wal-Mart, or even Radio Shack. These come in ratings from
fractional amps up to 60 amps. </p>
</blockquote>
<p>Choosing the correct rating for the fuse is not difficult. Measure the current
draw of your power system on the bench, or calculate it using software such as
ElectriCalc. Put the largest or pitchiest prop on that you expect to fly with.
Take the static current you've just measured/derived and multiply by about 1.25.
This 25% margin will allow for taking off in tall grass and should prevent nuisance
blows. Find the fuse with a rating at or just above this current level. </p>
<p>Where is the fuse installed? Most people put them in the wiring harness between the
battery and the speed control. Blade connectors can be used for the auto fuses. I prefer
to solder the fuse into the motor battery itself, which provides protection for the pack
when it is removed from the plane. The only drawback to this method is that it isn't
field-replaceable, but in the years since I've been doing this, I've only blown fuses
twice, stubbornly trying to take off from tall grass. </p>
<blockquote>
<p><font color="#FF0000">Cost of safety: $1 for fuse, <30 minutes to install</font> </p>
<p><font color="#FF0000">Cost of accident: $100 motor or worse</font> </p>
<p><font color="#FF0000">Which is the better choice?</font> </p>
</blockquote>
<hr>
<p><font size="4">III. Characteristics of the nicad battery</font> </p>
<p>A tank of glow fuel has some chemical safety issues. Similarly, the nicad battery pack
we use to power our planes has its own characteristics we need to remember. The most
important and obvious is the very low internal impedance of the nicad cell. This means
that, when shorted, the nicad can supply extremely high currents. I've personally measured
current pulses of 160 amps from a nicad pack in the lab, and this was under controlled
conditions with a current-limiting resistance in the circuit. (Guess what I was measuring?
Clearing characteristics of some of NASA's fuses). </p>
<p>Many early electric planes were designed to hold one fixed nicad pack, which was
charged while in the plane. Many, if not most, electric fliers now have multiple
packs for each plane to get more flying time at the field. These packs are removed
from the plane for cooling and recharging. The high-current capability of nicad
cells demands careful attention to safety when constructing, handling, and storing these
packs. The pack should be constructed so that a minimum of one durable layer of
insulation is between each cell and its neighbor, and the joint area between the positive
top of the cell and the negative case should be protected carefully. The overall pack
should be insulated so that no metal is exposed anywhere. </p>
<p>Once when I was younger and more foolish I made a seven-cell pack for a sailplane,
and I left the cell ends uninsulated to get extra cooling air over the cells. I was
careful not to set the pack on any metal part of my car while I was charging it, and I
thought I was being pretty safe. Well, one day I picked up the pack after charging while
wearing my 10-karat college ring. As you probably know, gold is one of the best electric
conductors, and my ring made a nice low-impedance short across two of the cells. I didn't
know this until about 50 milliseconds after I picked up the pack, when my finger felt like
it was on fire! I instinctively dropped the pack, and then figured out what I'd done and
quickly took off my ring. It was just in time to see a nice second-degree-burn
blister forming. Fortunately, there was no permanent damage. </p>
<p>I now insulate my packs completely. I think it only makes sense. I'd rather
have my packs one or two degrees warmer, than to set something on fire (like me). </p>
<blockquote>
<p><font color="#FF0000">Cost of safety: $0.25 for insulating tape or shrink wrap</font> </p>
<p><font color="#FF0000">Cost of accident: whatever it takes to replace the thing you've
burnt to a crisp.</font> </p>
<p><font color="#FF0000">Which one makes more sense?</font> </p>
</blockquote>
<hr>
<p>To summarize: use an arming switch and a fuse. Insulate your packs completely.
Give our power sources the respect they deserve, and use common sense too. </p>
<p>The college-ring incident made me a safety evangelist. Get the religion, brother!
The costs are low, and the benefits high. </p>
<hr>
<p><font size="4">Update on my winter project, the Yellow Jacket</font> </p>
<p><a href="/articles/ezonemag/sporttop/pete0197.htm">Last month </a>I introduced my current winter project, a 28%
scale Formula I racer. In the last month, I've progressed at my usual rate (slowly).
The orders for contest balsa, fiberglass, and carbon fiber are in and I've got the
wing design done. I've picked, with the usual friendly help of <a href="/articles/ezonemag/sporttop/../../pages/maillist.htm">Eflight </a>mail-list people (especially Tom Hunt), the
NACA2411 airfoil for the wing, with a 3 degree washout at the tips. I'm working on
plotting out all the ribs with some cool free software called <a href="http://www.crl.com/~spm/rec.models.rc.air.html">Plotfoil</a>. This software
can plot out any of the 1100 airfoils at the <a href="http://opus.aae.uiuc.edu/~selig/ads.html">UIUC airfoil site</a>, or any
similarly-formatted file with airfoil coordinates. An airfoil can be plotted with a
specific chord, spar location, sheeting thickness allowance, etc. so that a complete set
of rib templates can be made. The output can be sent to a laser or inkjet printer,
although the list of print drivers is somewhat short - the program was written for
Postscript printers. When I've got all the ribs plotted, I'll glue the templates to the
rib stock with 3M 77 spray adhesive, and start cutting. By next month, I hope to
have the wing framed up and be working on the fuselage. By publicly posting this, I'm
giving myself a little extra incentive to get this done! </p>
<hr>
<p><font size="4">New email address</font> </p>
<p>I've changed home internet providers in the last week, and therefore my email address
has changed from Pete_OShea(at)msn.com to <a href="http://rcgroups.com/shared/nospam.php?u=oshea&d=thecia.net">oshea(at)thecia.net</a>
(no, I haven't become a spy, it stands for The Complete Internet Access). I
apologize to anyone who's sent me email in the last week at the old address, because I may
have missed a few messages in the switch. My address at <a href="http://rcgroups.com/shared/nospam.php?u=peter.oshea&d=analog.com">work</a> is unchanged. </p>
<p><strong>Editor's note: You can also reach Pete at his address here on the E Zone, which
is <a href="http://rcgroups.com/shared/nospam.php?u=poshea&d=ezonemag.com">poshea(at)ezonemag.com</a>. This address is a
forwarding address which will always be set to Pete's current email address, wherever he
travels.</strong></p>
<hr>
<p>Catch you on the flip side, </p>
<p>Pete </p>
<p><a href="http://rcgroups.com/shared/nospam.php?u=oshea&d=thecia.net">E-mail</a> the author </p>
<p><a href="/articles/ezonemag/sporttop/petebio.htm">About </a>the author </p>
<p>This column is copyrighted (c) 1997 by Peter O'Shea and may not be reprinted or
retransmitted without proper attribution to the author and the E-Zone.
<p>This month I want to write about safety issues, both equipment to install in our
planes, and procedures we should follow. I'll only try to cover things that are
specific to electric-powered airplanes. General safety topics are addressed in the
AMA Safety Code, as well as by common sense. </p>
<p>There are three areas where, I believe, electrics differ significantly from
fuel-powered planes and need special attention. One is the instant-on characteristic
of electric motors, another is the capability of a motor to deliver torque and consume
power at stall, and the third is the special characteristics of a nicad battery pack that
merit consideration. </p>
<hr>
<p><font size="4">I. Electric motors can start instantly!</font> </p>
<p>You've seen it hundreds of times. The spinning, the valve-tweaking, the
fuel-priming, the glow-plug changing, the swearing.....yes, starting a glow-powered engine
is a real pain. To top it off, as soon as the plane gets to the runway, the engine dies!
Not so with electrics, of course. We're blessed with easy-starting, reliable power. But
that blessing comes at a cost, and that cost is <u>vigilance</u>. The spinning prop
attached to our motors can send you to the emergency room, but fast. Some wise
precautions to take are:
<ol>
<li>Don't connect the motor battery until you have your frequency pin (or other frequency
clearance means) and are ready to put the plane on the runway or hand-launch. </li>
<li>Don't turn on the radio system until you are ready for your flight. Turn off the
radio system as soon as possible after the flight. </li>
<li>Make sure that the throttle is set to off <u>before</u> turning on your transmitter.
Many digital speed controls have a function that won't allow the motor to turn until the
throttle stick has been in, or moved to, the low position. Don't make it a habit of
testing this function. </li>
<li>Motor-on radio checks must be done with the aid of a helper. </li>
<li>Check the leading edge and tip of your prop for molding flash, if it's not a wood prop.
Carefully sand away molding flash with fine sandpaper. </li>
</ol>
<p>Even these precautions aren't enough for high-powered planes. Any plane with the
potential to cause injury from the spinning prop needs a redundant safety system. Just
where to draw this line is debatable, but I recommend that any plane larger than speed 400
size (approximately 100 watts and above) have an arming switch. The arming switch
is, simply, a cutoff switch that goes between the battery and anything else in the plane.
The arming switch is left off until the plane is ready to taxi out to the runway (or
be hand-launched). When retrieving the plane after the flight, the arming switch is
the first thing turned off. </p>
<p>One argument against using an arming switch is that it adds a power loss to our limited
power budget. When used properly, an arming switch will not cause any noticeable
drop in system power. The simple secret to a long-lasting, low-loss arming switch is
this: NEVER SWITCH CURRENT with the arming switch. The switch should only <u>carry</u>
current. This means that you never turn the switch to "on" until the throttle is
in the low position, and similarly after the flight the switch is only turned
"off" after the throttle is again in the low position. The reason behind
this is simple: inductive loads, such as our electric motors, cause small arcs between the
metal contacts when the switch is actuated (especially on the opening, or breaking
action). The arcs cause pitting of the contacts and the formation of carbon deposits. This
makes the switch resistance go up, causing us to lose precious power in the switch. In
extreme cases, the contacts can even be welded together (I saw this more than once as a
failure analysis engineer at NASA). </p>
<p>The arming switch, when used properly, adds the critical element of redundancy against
the power system inadvertently turning on. A good arming switch for general use is
sold by Jomar and available through New Creations RC. This switch is a double-pole
rocker switch with a plastic package, and is relatively small and lightweight. Radio
Shack also carries a few automobile rocker switches that have appropriate current ratings,
but are somewhat larger. Digi-Key carries a wide selection of switches, any number
of which could be used. Try to find a switch with a current rating of 10 to 20A per pole,
which will be acceptable for sport use. </p>
<blockquote>
<p><font color="#FF0000">Cost of safety: <$5 for switch, 30 minutes or less to install</font>
</p>
<p><font color="#FF0000">Cost of accident: blood, stitches, tendon and/or nerve damage</font>
</p>
<p><font color="#FF0000">Which one is the sensible choice?</font> </p>
</blockquote>
<hr>
<p><font size="4">II. At stall, an electric motor delivers torque and draws current</font>
</p>
<p>When a fuel-powered engine stalls, or is stopped, it is dead. It does nothing, is
quiet (finally!) and produces no oily exhaust. When an electric motor is stalled by
mechanically stopping the prop, it goes into an entirely different state (assuming the
throttle is in the "on" position). The current becomes limited only by the
total resistance of the circuit - a sum of nicad internal impedance, wiring harness
resistance, speed control resistance, and motor armature resistance. The current will
be I = Vbattery / Rtotal. This total resistance is (if you've built your system well)
low. The current might well be over a hundred amps, if not more. </p>
<p>Who cares about a bit of extra current? You will, if it causes some part of your
system to overheat enough to start a fire. You'll care even more if this fire
spreads to the dry grass surrounding your flying field where your plane has crashed (ok,
maybe I'm being a bit alarmist). Your wallet will care if your motor or speed
control is smoked and unusable. </p>
<p>How do we fight this fire? By preventing it in the first place, using a
time-tested device that automatically cuts off the current when it gets dangerously high.
I'm talking about, of course, the humble fuse. Fuses are ancient devices, dating
back to the ancient Romans (well, maybe not)....ok, back to the beginnings of electric
power systems about a hundred years ago. A fuse is just a conductor of a controlled
length, thickness, and composition, which is designed to overheat and melt at a specified
current level. The melted fuse material falls away from the unmelted portion,
breaking the electrical connection and interrupting the current flow. </p>
<p>The fuse is the ultimate in safety protection - it is impossible for it to fail in an
unsafe manner. Yes, I'm an engineer, and I said "impossible". That is, a fuse
can open when not wanted (termed a "nuisance blow"), but a fuse made with the
correct element in the correct diameter CANNOT fail to clear when the specified current is
exceeded. Well, actually, if the current is extremely high (10,000 amps might do
it), a plasma can be formed inside the fuse and it will keep conducting current. For
our application, I'm going to still call that impossible (the internal resistance of our
current source, the nicad, limits the current to levels well below this). No other
current protection scheme can offer this level of protection. </p>
<p>And it only costs a buck or less. It can weigh as low as a few measly grams.
There is NO EXCUSE NOT TO USE ONE. </p>
<p>Have I convinced you yet? Ok, now let's talk about which fuse to use: </p>
<blockquote>
<p>For speed 400 systems: the Littelfuse Picofuse, available through Digi-Key
(1-800-DIGIKEY) for about a buck apiece. These are the size of a 1/4 watt resistor
and have ratings up to 15 amps. </p>
<p>For higher-powered planes: the automotive blade fuse, available at your local auto
parts dealer, K-Mart, Wal-Mart, or even Radio Shack. These come in ratings from
fractional amps up to 60 amps. </p>
</blockquote>
<p>Choosing the correct rating for the fuse is not difficult. Measure the current
draw of your power system on the bench, or calculate it using software such as
ElectriCalc. Put the largest or pitchiest prop on that you expect to fly with.
Take the static current you've just measured/derived and multiply by about 1.25.
This 25% margin will allow for taking off in tall grass and should prevent nuisance
blows. Find the fuse with a rating at or just above this current level. </p>
<p>Where is the fuse installed? Most people put them in the wiring harness between the
battery and the speed control. Blade connectors can be used for the auto fuses. I prefer
to solder the fuse into the motor battery itself, which provides protection for the pack
when it is removed from the plane. The only drawback to this method is that it isn't
field-replaceable, but in the years since I've been doing this, I've only blown fuses
twice, stubbornly trying to take off from tall grass. </p>
<blockquote>
<p><font color="#FF0000">Cost of safety: $1 for fuse, <30 minutes to install</font> </p>
<p><font color="#FF0000">Cost of accident: $100 motor or worse</font> </p>
<p><font color="#FF0000">Which is the better choice?</font> </p>
</blockquote>
<hr>
<p><font size="4">III. Characteristics of the nicad battery</font> </p>
<p>A tank of glow fuel has some chemical safety issues. Similarly, the nicad battery pack
we use to power our planes has its own characteristics we need to remember. The most
important and obvious is the very low internal impedance of the nicad cell. This means
that, when shorted, the nicad can supply extremely high currents. I've personally measured
current pulses of 160 amps from a nicad pack in the lab, and this was under controlled
conditions with a current-limiting resistance in the circuit. (Guess what I was measuring?
Clearing characteristics of some of NASA's fuses). </p>
<p>Many early electric planes were designed to hold one fixed nicad pack, which was
charged while in the plane. Many, if not most, electric fliers now have multiple
packs for each plane to get more flying time at the field. These packs are removed
from the plane for cooling and recharging. The high-current capability of nicad
cells demands careful attention to safety when constructing, handling, and storing these
packs. The pack should be constructed so that a minimum of one durable layer of
insulation is between each cell and its neighbor, and the joint area between the positive
top of the cell and the negative case should be protected carefully. The overall pack
should be insulated so that no metal is exposed anywhere. </p>
<p>Once when I was younger and more foolish I made a seven-cell pack for a sailplane,
and I left the cell ends uninsulated to get extra cooling air over the cells. I was
careful not to set the pack on any metal part of my car while I was charging it, and I
thought I was being pretty safe. Well, one day I picked up the pack after charging while
wearing my 10-karat college ring. As you probably know, gold is one of the best electric
conductors, and my ring made a nice low-impedance short across two of the cells. I didn't
know this until about 50 milliseconds after I picked up the pack, when my finger felt like
it was on fire! I instinctively dropped the pack, and then figured out what I'd done and
quickly took off my ring. It was just in time to see a nice second-degree-burn
blister forming. Fortunately, there was no permanent damage. </p>
<p>I now insulate my packs completely. I think it only makes sense. I'd rather
have my packs one or two degrees warmer, than to set something on fire (like me). </p>
<blockquote>
<p><font color="#FF0000">Cost of safety: $0.25 for insulating tape or shrink wrap</font> </p>
<p><font color="#FF0000">Cost of accident: whatever it takes to replace the thing you've
burnt to a crisp.</font> </p>
<p><font color="#FF0000">Which one makes more sense?</font> </p>
</blockquote>
<hr>
<p>To summarize: use an arming switch and a fuse. Insulate your packs completely.
Give our power sources the respect they deserve, and use common sense too. </p>
<p>The college-ring incident made me a safety evangelist. Get the religion, brother!
The costs are low, and the benefits high. </p>
<hr>
<p><font size="4">Update on my winter project, the Yellow Jacket</font> </p>
<p><a href="/articles/ezonemag/sporttop/pete0197.htm">Last month </a>I introduced my current winter project, a 28%
scale Formula I racer. In the last month, I've progressed at my usual rate (slowly).
The orders for contest balsa, fiberglass, and carbon fiber are in and I've got the
wing design done. I've picked, with the usual friendly help of <a href="/articles/ezonemag/sporttop/../../pages/maillist.htm">Eflight </a>mail-list people (especially Tom Hunt), the
NACA2411 airfoil for the wing, with a 3 degree washout at the tips. I'm working on
plotting out all the ribs with some cool free software called <a href="http://www.crl.com/~spm/rec.models.rc.air.html">Plotfoil</a>. This software
can plot out any of the 1100 airfoils at the <a href="http://opus.aae.uiuc.edu/~selig/ads.html">UIUC airfoil site</a>, or any
similarly-formatted file with airfoil coordinates. An airfoil can be plotted with a
specific chord, spar location, sheeting thickness allowance, etc. so that a complete set
of rib templates can be made. The output can be sent to a laser or inkjet printer,
although the list of print drivers is somewhat short - the program was written for
Postscript printers. When I've got all the ribs plotted, I'll glue the templates to the
rib stock with 3M 77 spray adhesive, and start cutting. By next month, I hope to
have the wing framed up and be working on the fuselage. By publicly posting this, I'm
giving myself a little extra incentive to get this done! </p>
<hr>
<p><font size="4">New email address</font> </p>
<p>I've changed home internet providers in the last week, and therefore my email address
has changed from Pete_OShea(at)msn.com to <a href="http://rcgroups.com/shared/nospam.php?u=oshea&d=thecia.net">oshea(at)thecia.net</a>
(no, I haven't become a spy, it stands for The Complete Internet Access). I
apologize to anyone who's sent me email in the last week at the old address, because I may
have missed a few messages in the switch. My address at <a href="http://rcgroups.com/shared/nospam.php?u=peter.oshea&d=analog.com">work</a> is unchanged. </p>
<p><strong>Editor's note: You can also reach Pete at his address here on the E Zone, which
is <a href="http://rcgroups.com/shared/nospam.php?u=poshea&d=ezonemag.com">poshea(at)ezonemag.com</a>. This address is a
forwarding address which will always be set to Pete's current email address, wherever he
travels.</strong></p>
<hr>
<p>Catch you on the flip side, </p>
<p>Pete </p>
<p><a href="http://rcgroups.com/shared/nospam.php?u=oshea&d=thecia.net">E-mail</a> the author </p>
<p><a href="/articles/ezonemag/sporttop/petebio.htm">About </a>the author </p>
<p>This column is copyrighted (c) 1997 by Peter O'Shea and may not be reprinted or
retransmitted without proper attribution to the author and the E-Zone.