Today's Message Index:
----------------------
1. 05:10 AM - Re: Do reporters ever get it right? (Peter Laurence)
2. 06:22 AM - Re: Crowbar O.V. & Internally Regulated (Robert L. Nuckolls, III)
3. 06:49 AM - Re: Shielding the tach lead (Robert L. Nuckolls, III)
4. 07:25 AM - Re: SDK-1 dimmer kit for EL ??? (Robert L. Nuckolls, III)
5. 07:44 AM - Dual battery question (Robert L. Nuckolls, III)
6. 07:45 AM - Re: SDK-1 dimmer kit for EL ??? (Flexible Electroluminescent Lighting, 888 457-0117)
7. 09:27 AM - Autocad fonts (David Carter)
8. 10:55 AM - Re: Crowbar O.V. & Internally Regulated Alternator (Z-24) (Haywire)
9. 01:00 PM - Re: 10685 Polit (Robert L. Nuckolls, III)
10. 01:00 PM - Re: Crowbar O.V. & Internally Regulated Alternator (Z-24) (Steve Sampson)
11. 03:21 PM - Re: Shielding the tach lead (Duncan McBride)
12. 03:37 PM - Re: Autocad fonts (Robert L. Nuckolls, III)
13. 09:02 PM - Connectors et. als. (Robert L. Nuckolls, III)
14. 10:27 PM - Antenna tuning (Rob W M Shipley)
15. 11:52 PM - Carling LT series of toggle switches (Charlie Kuss)
Message 1
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| Subject: | Re: Do reporters ever get it right? |
--> AeroElectric-List message posted by: "Peter Laurence" <plaurence@the-beach.net>
Bob,
Anyone who runs out of fuel should have his license suspended for one year.
Secondly,
The fuel gauges in his/her car should be disabled and replaced with a
timer.
Peter
do not archive
Interesting tid-bit from latest Avweb posing:
>
> http://www.avweb.com/newswire/9_31b/complete/185409-1.html#5e
>
> . . . I'm sitting here wondering how and "electrical failure"
> can force a landing in a high-wing, gravity fed fuel system
> aircraft.
>
> Even more bizarre is the item just below the one cited.
> Where can a pilot's head be at when an aircraft like this
> runs out of fuel?
>
>
> Bob . . .
>
> --------------------------------------------
> ( Knowing about a thing is different than )
> ( understanding it. One can know a lot )
> ( and still understand nothing. )
> ( C.F. Kettering )
> --------------------------------------------
>
>
Message 2
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| Subject: | Re: Crowbar O.V. & Internally Regulated |
Alternator (Z-24)
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 07:27 AM 8/1/2003 +0100, you wrote:
>--> AeroElectric-List message posted by: "Steve Sampson"
><SSampson.SLN21@london.edu>
>
>Bob - sorry if I am being a bit obtuse but there is something I cant figure
>out in your book.
>
>I am building and RV9a and already have a new internally regulated 60amp
>alternator (Nippondenso) from VANS so I think I will use it. I have been
>looking at Z-24 in order to minimise the fun of a runaway and am wondering
>why the alternator disconnect contactor is needed?
>
>In the event that the Crowbar OV trips the field current will go to zero and
>the alternator will stop producing power.
>
>If your answer is 'yes but an internal fault could put current back in the
>excitation windings' then my question is so why don't you have the same
>contactor in diags z-9 and z-23 for example? I guess the internals are less
>complex but its still a problem. Is this the case of belt braces AND a bit
>of string to hold your trousers up? I expect it is much more subtle than
>that though!
>
>Thanks, Steve
See:
http://216.55.140.222/FAQ/Internal_Regulator/
Bob . . .
Message 3
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| Subject: | Re: Shielding the tach lead |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 07:39 PM 7/31/2003 -0400, you wrote:
>--> AeroElectric-List message posted by: "Duncan McBride"
><duncanmcbride@comcast.net>
>
>I called Lockwood aviation for any ideas they may have about reducing
>noise. You may recall I'm getting a lot of raspy white noise in a
>Microair 760 when the PTT is pushed. I get the same noise when the radio
>is completely isolated from the aircraft's (Kolb Twinstar Mk III, Rotax
>912UL) and powered by a battery, so I'm working under the theory that I
>need to reduce radiated noise. The guys at Lockwood immediately asked if
>I had shielded the tach lead. They said this is a problem they see a
>lot. There are two leads from the Rotax that in the installation manual
>are shown going to a "rev-counter". I have the Grand Rapids EIS, which
>calls for one of the leads to be grounded, and the other to go to pin #6
>of the unit. So here is my question - if I use shielded wire for the lead
>going to pin 6, do I ground the shielding at both ends? Or could I
>connect the shielding to the second Rotax lead and ground it at the panel
>near the EIS? The simplest thing would be to ground th!
>e shielding and the second lead on the grounding block near the engine. I
>don't know, it's just hard for me to believe that the tach lead could
>really be the problem, but I'm trying anything I hear, and I'd like to
>give this a shot. Any thoughts?
I think that tach signal comes off the AC output of the
PM alternator. It's almost a sine wave and very low frequency . . .
perhaps on the order of 200 Hz, I share your doubts as to
the probability of this being a noise source.
Try any and all combinations of shield grounding including
not having shields connected at all. I suspect there will
be no observable difference in noise.
Who is hearing the noise. When PTT is pushed, do the
folks you are talking to hear it? If you're hearing it,
then it's part of the sidetone audio routed to the headsets
to monitor radio performance and inprove diction while
transmitting. See if the same thing happens with just
the intercom PTT activated. This would help isolated the
problem down by eliminating or confirming participation
of the transmitter.
I presume your microphone and headset jacks are insulated
from any electrical connection with the airframe . . .
Bob . . .
Message 4
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| Subject: | Re: SDK-1 dimmer kit for EL ??? |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 05:57 AM 7/31/2003 +0000, you wrote:
>--> AeroElectric-List message posted by: "Amit Dagan" <amitdagan@hotmail.com>
>
>Q:
>I have an automotive aftermarket electro-luminescense kit that plugs into
>the 12v cigarette lighter socket, and you stick the 16" EL strips where ever
>you like in your car (double sided sticky tape included).
>Ofcourse I like the price (~$30 at GIJoes) for a panel light system, and I
>will install this on the underside of the glare shield.
>
>I was wondering, other than controlling the frequency in the EL converter,
>if I used one of the dimmers in your sdk-1 kit,in series before the power
>supply to the EL converter, would that dim the light ?
>The EL kit takes 12v, 60milliAmps (0.72Watts).
The SDK-1 is a rheostat that is specific to the
control of an incandescent lamp with a current draw
of 220 to 250 mA. Any other lamp load would not yield
satisfactory behavior.
You need a voltage-regulated dimmer like the
DIM5-14 at:
http://www.bandc.biz/cgi-bin/ez-catalog/cat_display.cgi?10X358218
or build your own like:
http://216.55.140.222/temp/DimFab.pdf
You may find that full counter-clockwise rotation of the
potentiometer is too dim for this lighting technology.
If so, make a measurement of the voltage that produces
the desired minimum light output. Give me the value
and I'll calculate new resistor sizes to give you
the proper range of control for the potentiometer.
Bob . . .
Message 5
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| Subject: | Dual battery question |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 05:32 PM 5/30/2003 -0500, you wrote:
>Hi Bob.
>First, thanks for writing your book and providing the wealth of info on
>your website.
>
>Perhaps this is a new and increasingly popular requirement, but here's my
>situation-
>
>With the new EFIS type engine monitors, there's a need to keep their
>supply voltage up during cranking. BM EFIS One, for example, takes 90
>seconds to boot, and will drop off during cranking. So, without 2
>batteries, you can't tell what the engine sensors are sensing for a long
>time after startup.
>
>My thinking is that the combination of good batterie(s) and low-drain
>systems leads to an adequate reserve from 2 batteries, negating the need
>for dual alternators. (gee.. almost an Alan Greenspan sentence..)
>
>I'm building a Cozy MkIV and planning to implement my electrical system as
>in the "generic light aircraft electrical system". Since I only add 135lb
>to the plane, I'd like to put as small a battery as I can in the back and
>still crank the 360. I'd like to keep the essential bus voltage up during
>cranking, so I thought I'd add a battery up front which (for
>simplification) wouldn't be used for cranking but would be kept afloat by
>the alternator. If I lose the alternator, I'd like to be able to use both
>batteries in sequence to feed the essential bus.
>
>So, my thought was to simply connect the aux battery to the other end of
>the SPDT essential-bus-alt-feed switch. If that would be ok, I'd instead
>use a DP3T switch for OFF / ESSN-ALT-FEED / AUX-BAT-FEED. That way, all
>switches are down when you walk away. My concern is that recharging the
>aux battery could put too much load on the switch or isolation diode. How
>much current might a 10-20Ah battery draw to charge?
Why not put in dual batteries in a Figure Z-11 with Z-30 addition
of second battery. Run ENDURANCE bus from aux battery. For
startup, close e-bus alternate feed switch and get ATIS and
clearance. EFIS system comes up during this time too.
Close only main battery switch and start engine. After engine
start, close aux battery switch and turn e-bus alternate feed
switch off.
In this case, you'd put a new battery in aux battery location
every year and move aux battery to main battery slot. Your
e-bus en route loads should STILL be sized to allow continue
flight to intended destination AUX battery only.
You ALWAYS have access to both batteries by closing both
contactors . . . but with planning and considered checklist,
you'll never find yourself short of electrons before you
find yourself short of fuel.
Bob . . .
Message 6
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| Subject: | Re: SDK-1 dimmer kit for EL ??? |
--> AeroElectric-List message posted by: "Flexible Electroluminescent Lighting,
888 457-0117" <beingseen@comcast.net>
Hello Robert,
Placing the dimmer between the inverter and the power source will enable you
to control the brightness of the lamp. The brightness of the lamp is
effected by the level of voltage being supplied to the inverter and in turn
to the lamp. Hope this helps.
Ed
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
Subject: Re: AeroElectric-List: SDK-1 dimmer kit for EL ???
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<bob.nuckolls@cox.net>
>
> At 05:57 AM 7/31/2003 +0000, you wrote:
> >--> AeroElectric-List message posted by: "Amit Dagan"
<amitdagan@hotmail.com>
> >
> >Q:
> >I have an automotive aftermarket electro-luminescense kit that plugs into
> >the 12v cigarette lighter socket, and you stick the 16" EL strips where
ever
> >you like in your car (double sided sticky tape included).
> >Ofcourse I like the price (~$30 at GIJoes) for a panel light system, and
I
> >will install this on the underside of the glare shield.
> >
> >I was wondering, other than controlling the frequency in the EL
converter,
> >if I used one of the dimmers in your sdk-1 kit,in series before the power
> >supply to the EL converter, would that dim the light ?
> >The EL kit takes 12v, 60milliAmps (0.72Watts).
>
> The SDK-1 is a rheostat that is specific to the
> control of an incandescent lamp with a current draw
> of 220 to 250 mA. Any other lamp load would not yield
> satisfactory behavior.
>
> You need a voltage-regulated dimmer like the
> DIM5-14 at:
>
> http://www.bandc.biz/cgi-bin/ez-catalog/cat_display.cgi?10X358218
>
> or build your own like:
>
> http://216.55.140.222/temp/DimFab.pdf
>
> You may find that full counter-clockwise rotation of the
> potentiometer is too dim for this lighting technology.
> If so, make a measurement of the voltage that produces
> the desired minimum light output. Give me the value
> and I'll calculate new resistor sizes to give you
> the proper range of control for the potentiometer.
>
> Bob . . .
>
>
Message 7
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--> AeroElectric-List message posted by: "David Carter" <dcarter@datarecall.net>
Bob,
You have previously mentioned a way to substitute ROMANT.SHX (??) for the default
Autocad font.
I noticed today, when I opened your Z12h.dwg that my Intellicad program did the
following:
"Substituting font [ICAD.FNT] for font [ROMANS.shx].
"Substituting font [ICAD.FNT] for font [VELVET-L.SHX].
"Substituting font [ICAD.FNT] for font [ROMANT.SHX].
Would you please give the reason for your preference for a particular font (or
fonts) and how to make one be the default?
Also, when I tried to open Z11h.dwg, I got "bad DWG info". I'll re-download that
one from your site. The others have been opening just fine.
David Carter
Message 8
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| Subject: | Crowbar O.V. & Internally Regulated Alternator |
(Z-24)
--> AeroElectric-List message posted by: "Haywire" <haywire@telus.net>
Hi Bob
I used an internally regulated alternator (ND) and installed the B-lead
contactor. I ordered the components from Digi-Key to build the OVM but one
item was backordered (just got the notice it has shipped), so I don't
currently have any overvoltage protection. But it's an extremely rare
occurrence right? After all I've never had an overvoltage in 20 years of
driving automobiles.
Well, after about an hour of taxi-testing in 30C+ weather under various
load conditions, to test the cooling system under worst case conditions (oh
yeah, and to have some fun... dreaming of flight :-), I noticed my system
voltage at just over 16 volts. I immediately pulled the fuse, opening the
B-lead contactor and taxied back to the hanger. After shut-down and cowl
removal, I found the alt. to be to hot to hold my hand on. On restart with
the fuse back in it would not charge at all. I'm not certain if the heat
contributed to it's failure.
So I removed the internal regulator, and went to the auto parts store.
New
reg was $30 and would be shipped overnight. 1975 Ford reg was $9 and he had
40 0f 'em in stock. So I bought the Ford reg. The alt brush leads needed to
be modified and a small aluminium bracket had to be fabricated to take the
place of the internal reg. It took about 1 1/2 hours to make this mod, of
which about an hour was spent just studying the best way to do it. Actual
work was less than 30 min. It works great.
Now I have the regulator mounted on the firewall near the battery in a
cooler location. It works perfectly and if it ever does fail, I know I can
get another cheap & anywhere. Since I already have the B-lead contactor
installed, I decided to leave it so even though it is extremely unlikely I
will be protected in the event of a "mooney-like" fault. I wouldn't have
gone to the trouble of installing this contactor just for this, but since
its already there... I will build and install the OVM within a few days.
I just thought I'd pass this along as an example of why Bob's always
right.... :-)
S. Todd Bartrim
Turbo 13B RV-9Endurance
C-FSTB
http://www3.telus.net/haywire/RV-9/C-FSTB.htm
"Whatever you vividly imagine, Ardently desire, Sincerely believe in,
Enthusiastically act upon, Must inevitably come to pass".
> -----Original Message-----
> From: owner-aeroelectric-list-server@matronics.com
> [mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Robert
> L. Nuckolls, III
> Sent: Friday, August 01, 2003 6:21 AM
> To: aeroelectric-list@matronics.com
> Subject: Re: AeroElectric-List: Crowbar O.V. & Internally Regulated
> Alternator (Z-24)
>
>
> --> AeroElectric-List message posted by: "Robert L. Nuckolls,
> III" <bob.nuckolls@cox.net>
>
> At 07:27 AM 8/1/2003 +0100, you wrote:
> >--> AeroElectric-List message posted by: "Steve Sampson"
> ><SSampson.SLN21@london.edu>
> >
> >Bob - sorry if I am being a bit obtuse but there is something I
> cant figure
> >out in your book.
> >
> >I am building and RV9a and already have a new internally regulated 60amp
> >alternator (Nippondenso) from VANS so I think I will use it. I have been
> >looking at Z-24 in order to minimise the fun of a runaway and am
> wondering
> >why the alternator disconnect contactor is needed?
> >
> >In the event that the Crowbar OV trips the field current will go
> to zero and
> >the alternator will stop producing power.
> >
> >If your answer is 'yes but an internal fault could put current
> back in the
> >excitation windings' then my question is so why don't you have the same
> >contactor in diags z-9 and z-23 for example? I guess the
> internals are less
> >complex but its still a problem. Is this the case of belt braces
> AND a bit
> >of string to hold your trousers up? I expect it is much more subtle than
> >that though!
> >
> >Thanks, Steve
>
> See:
>
> http://216.55.140.222/FAQ/Internal_Regulator/
>
> Bob . . .
>
>
Message 9
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--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
>My alternator field circuit breaker keeps popping after running the engine
>less than 1/2 hour. I have your overvoltage protector, and find that
>current varies linearly with input voltage on the bench. At 16.81V (near
>trigger pt.) I get about 1.7 mA. I'm using a 10k pot on a variable DC
>power supply and measuring both the voltage and current.
>
>I thought the device was supposed to be an open circuit until
>it got to the trigger point.
There is a voltage divider inside that scales input voltage
down to the operating range of the trigger device so it
will draw a few milliamperes. It is all practical purposes
an open circuit and the small current you observed is not
an indicator of bad/failed device.
>Should I replace the overvoltage protector?
Are you watching bus voltage when the trip event happens?
Maybe the ov module is doing exactly what it is supposed to
be doing?
> Also, once it fires, do you have a suggestion for a reset?
I presume you have the recommended circuit breaker
in series with this device. Pushing the breaker back
in resets the system.
>Turning off the master on our plane would cut the engine.
???? why would you do this ???? I can deduce
no reason why an engine should be dependent upon
position of the DC Power Master Switch . . . and
in fact, recommend that all electrically dependent
engine components run from an always-hot battery
bus.
What engine/alternator combination are you using?
Bob . . .
--------------------------------------------
( Knowing about a thing is different than )
( understanding it. One can know a lot )
( and still understand nothing. )
( C.F. Kettering )
--------------------------------------------
Message 10
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| Subject: | Crowbar O.V. & Internally Regulated Alternator |
(Z-24)
--> AeroElectric-List message posted by: "Steve Sampson" <SSampson.SLN21@london.edu>
Bob - thanks for that VERY high quality answer. I will get one more
contactor since that all makes excellent sense. Thanks, Steve.
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert
L. Nuckolls, III
Subject: Re: AeroElectric-List: Crowbar O.V. & Internally Regulated
Alternator (Z-24)
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<bob.nuckolls@cox.net>
At 07:27 AM 8/1/2003 +0100, you wrote:
>--> AeroElectric-List message posted by: "Steve Sampson"
><SSampson.SLN21@london.edu>
>
>Bob - sorry if I am being a bit obtuse but there is something I cant figure
>out in your book.
>
>I am building and RV9a and already have a new internally regulated 60amp
>alternator (Nippondenso) from VANS so I think I will use it. I have been
>looking at Z-24 in order to minimise the fun of a runaway and am wondering
>why the alternator disconnect contactor is needed?
>
>In the event that the Crowbar OV trips the field current will go to zero
and
>the alternator will stop producing power.
>
>If your answer is 'yes but an internal fault could put current back in the
>excitation windings' then my question is so why don't you have the same
>contactor in diags z-9 and z-23 for example? I guess the internals are less
>complex but its still a problem. Is this the case of belt braces AND a bit
>of string to hold your trousers up? I expect it is much more subtle than
>that though!
>
>Thanks, Steve
See:
http://216.55.140.222/FAQ/Internal_Regulator/
Bob . . .
Message 11
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| Subject: | Re: Shielding the tach lead |
--> AeroElectric-List message posted by: "Duncan McBride" <duncanmcbride@comcast.net>
I'll try to address your points in order
Sine wave low frequency tach signal? I'm looking at the Rotax 912
installation manual and the specs for the rev-counter are one pulse per
revolution. The graphs on the documentation show a pretty sharp spike of at
least 5 volts at a load of 100 ohms and 75 volts at 100 kohms when at 5000
rpm. The German translation is a little vague - there are two graphs for
the 6000rpm oscillograms - one shows peak voltage at about 7V and the other
about 75V. Who knows? I thought I would at least disconnect the leads at
the engine, fire it up and see if the noise goes away. If it does I'll hook
up some shielded wire (or bolt up some conduit, what the hell)
As to who is hearing the noise, I am in my headphones for sure. It is
present when the radio and headphone connections are completely isolated
from the aircraft and the radio is powered with a battery as you suggested.
The 760 is grounded through the panel mounting screws, so I used nylon
mounting screws and confirmed that it was not grounded. None of the
headphone jacks or PTT leads were grounded, and the PTT switch lead went
back to the test battery, not the aircraft ground. When I had the 760
intercom feature hooked up, I did hear the noise when the intercom PTT was
pushed, so the problem is not exclusive to transmitting. Now I have a
Sigtronics Portable (powered by the internal 9-volt battery) hooked up to
the 760. When the transmit PTT is pushed I hear the very same noise through
the intercom, whether it is turned on or not. However, when not
transmitting and just the VOX squelch is broken on the intercom, I do not
hear the noise. I had the intercom converted to the high noise version and
I'm using Oregon Aero mic muffs on the headsets - this is working pretty
well, though the Twinstar cockpit is pretty noisy.
I once thought that only I was hearing the noise and that other planes or
the ground were not hearing it. That seems to have been inaccurate,
prompted by the report of a pilot who heard me in the pattern when the
engine was idling. Subsequent tests confirm the transmission at significant
power settings includes the raspy white-like noise.
Thanks very much for your time - I'll try disconnecting the tach leads
tomorrow and report.
----- Original Message -----
From: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
Subject: Re: AeroElectric-List: Shielding the tach lead
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<bob.nuckolls@cox.net>
>
> At 07:39 PM 7/31/2003 -0400, you wrote:
> >--> AeroElectric-List message posted by: "Duncan McBride"
> ><duncanmcbride@comcast.net>
> >
> >I called Lockwood aviation for any ideas they may have about reducing
> >noise. You may recall I'm getting a lot of raspy white noise in a
> >Microair 760 when the PTT is pushed. I get the same noise when the radio
> >is completely isolated from the aircraft's (Kolb Twinstar Mk III, Rotax
> >912UL) and powered by a battery, so I'm working under the theory that I
> >need to reduce radiated noise. The guys at Lockwood immediately asked if
> >I had shielded the tach lead. They said this is a problem they see a
> >lot. There are two leads from the Rotax that in the installation manual
> >are shown going to a "rev-counter". I have the Grand Rapids EIS, which
> >calls for one of the leads to be grounded, and the other to go to pin #6
> >of the unit. So here is my question - if I use shielded wire for the
lead
> >going to pin 6, do I ground the shielding at both ends? Or could I
> >connect the shielding to the second Rotax lead and ground it at the panel
> >near the EIS? The simplest thing would be to ground th!
> >e shielding and the second lead on the grounding block near the engine.
I
> >don't know, it's just hard for me to believe that the tach lead could
> >really be the problem, but I'm trying anything I hear, and I'd like to
> >give this a shot. Any thoughts?
>
> I think that tach signal comes off the AC output of the
> PM alternator. It's almost a sine wave and very low frequency . . .
> perhaps on the order of 200 Hz, I share your doubts as to
> the probability of this being a noise source.
>
> Try any and all combinations of shield grounding including
> not having shields connected at all. I suspect there will
> be no observable difference in noise.
>
> Who is hearing the noise. When PTT is pushed, do the
> folks you are talking to hear it? If you're hearing it,
> then it's part of the sidetone audio routed to the headsets
> to monitor radio performance and inprove diction while
> transmitting. See if the same thing happens with just
> the intercom PTT activated. This would help isolated the
> problem down by eliminating or confirming participation
> of the transmitter.
>
> I presume your microphone and headset jacks are insulated
> from any electrical connection with the airframe . . .
>
> Bob . . .
>
>
Message 12
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| Subject: | Re: Autocad fonts |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
At 11:27 AM 8/1/2003 -0500, you wrote:
>--> AeroElectric-List message posted by: "David Carter"
><dcarter@datarecall.net>
>
>Bob,
>
>You have previously mentioned a way to substitute ROMANT.SHX (??) for the
>default Autocad font.
>
>I noticed today, when I opened your Z12h.dwg that my Intellicad program
>did the following:
>"Substituting font [ICAD.FNT] for font [ROMANS.shx].
>
>"Substituting font [ICAD.FNT] for font [VELVET-L.SHX].
>
>"Substituting font [ICAD.FNT] for font [ROMANT.SHX].
>
>Would you please give the reason for your preference for a particular font
>(or fonts) and how to make one be the default?
Fonts to be used on any drawing are called out IN
THE FILE for the drawing you are working on. The only
reason there is a "default font" that AutoCAD or any
other drawing program seems to call for is because
unless you tell it otherwise, the application opens
a rudimentary, blank drawing file as soon as you
open the application.
Then, if you give the command "text" then it will
begin to create text in whatever font is defined as
"standard" in the "style" listing for that drawing.
For AutoCAD, that font is txt.shx or some such thing.
Never did like the looks of that font. For years
I used a font not generally offered with Autocad
that looks like Futura . . . a nice, block letter
with good legibility. This is the font called out
for many aviation placards and instrument faces.
The name of the font file was "velvet-l.shx"
On many of my drawings, you'll find the cad program
asking for velvel-l.shx which is why I include it
on my distribution disk and in the downloadable
drawings folder at
http://216.55.140.222/articles/Appendix_Z_Drawings
Now, when your cad program opens up one of my
drawings or anyone else's, you may find that
the application doesn't understand one or more
of the fonts called out on the drawing and it will
substitute something or ask you for a new
font file.
More recently, Autocad will use standard Windows
fonts in addition to the list of fonts supplied
with Autocad. You'll find less use of velvet-l
and more use of "Technic" which I believe is
a Windows font.
In any case, no mater what font is called out
on a drawing you open, you can change it at
will with the "style" command whereupon you'll
be given a list of existing style names
(which you can supply/edit) and their corresponding
font names (which will come from a list of
internal and external fonts recognized by the
application.)
>Also, when I tried to open Z11h.dwg, I got "bad DWG info". I'll
>re-download that one from your site. The others have been opening just fine.
I have to remember to "save" the uploaded files in the
oldest compatible AutoCAD format after I work on it
in ACAD2000. I may have fiddled with Z11 and
saved it in 2000 . . . I've just re-loaded it to
the server in Version 12 format which is as far
back as I can go. This should make the file
usable by any of the cad programs on my CD.
Bob . . .
Message 13
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| Subject: | Connectors et. als. |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <bob.nuckolls@cox.net>
>Comments on http://www.aeroelectric.com/articles/wingwire/wingwire.html
>wingroot connector state: "If they have a disadvantage it is . . . PVC
>non-plated 7 strand wire".
>Bob, any builder considering this could logically be assumed to also
>be fabricating various other connectors during the wiring of his aircraft,
>and so, would be likely to become knowledgeable about crimping pins onto
>ends of wires and inserting them into connector shell of his choice -
>using tefzel insulated multistrand plated wires (less long term-corrosion
>vs unplated wires).
Sure . . . but the vast majority of connector needs you
will encounter are already specified by the nature of
connectors supplied with a product. There are very few,
if any connectors, necessarily dictated by the builder.
One such case is wing roots for aircraft wherein the
user EXPECTS to routinely mate and de-mate the wire
bundle in the normal course of operation. Others
have indicated an interest in making instrument
panels "un-pluggable" from the rest of the airplane
as maintenance aid.
>Using individual wire knife splices seems a simpler choice, as long as
>each wire is propoerly identified by a heat-shrinked label.
. . . true if this were not an operational break in
the bundle as described above. If it were my RV or similar
ship, I would have NO connectors at the wing root. I'd
put a service loop in the wire bundles before they enter
the fuselage so that should removal be required, there's
enough slack to simply cut the wires for removal and
rejoin them with butt-splices.
>Using the auto connector doubles the number of connections on
>wire ends (splicing it into the system) over either knife
>splices or a non-pre-wired connector.
True again . . . but none of the lower-parts-count
techniques have the convenience of a low-cost, robust
connector designed for multiple assembly-disassembly
cycles like the trailer wiring connector I illustrated.
>For an RV-4/6/7/8/9/10 with an adequate space between wing
>and fuselage (or put connector inside fuselage), which is
>a covered area, not subject to oil contamination or heat,
>what would be good choices of connectors?
It's quite easy to leave wing wiring long enough to reach to
final destination inside the fuselage. Leave these
wires un-connected until after last assembly of wings
to fuselage. I'm flying rentals that are 40 years old
most of which have never had the wings off. Why introduce
a failure mode where no need for one exists?
>I would appreciate your recommendations of those, in addition
>to the auto-trailer connector. The rationale for breaking the
>wires is: Some of us, building at home, only put one wing on
>at a time, or even if we put on both, we commonly remove the
>wings for trailering to the airport. That alone is a rational
>reason for having a "break" in the wing wiring. "rented spam
>cans" are built completely in a factory, and thus the rationale
>for not breaking the wires is valid in that case, but not so
>for home-builders working at home and having to disassemble
>and trailer to an airport for the "final assembly line" work.
If you trailer the airplane routinely to fly from an
airport and store the aircraft at home, then by all means,
make the electrical interface between wings and fuselage
convenient to the task. If this is not an ongoing requirement
after the airplane is finished, then leave wires un-connected
until after wings receive final mate.
If you need a robust, low cost connector then the suggestion
for a trailer wiring connector can be considered. If you
want to spend the dollars and time to acquire and install
more "aircraft like" connectors, consider the MS3470
series connectors like:
http://www.qscomp.cz/Pdf/MIL-C-26482-PT-Series-AAO_8-11.pdf
Because I have tools to install these connectors -AND-
assuming I needed a wing root connector in an airplane I'm
building, I'd probably use these. A mated pair of these
critters can probably be had for something on the order
of $50-70 or $100-140 per ship-set. These are very "aircraft
like" in appearance and performance but about 15 times
the cost of the trailer connector.
A popular connector with the electronics industry
has been around for about 50 years. The so-called
Cinch-Jones series which you can observe at:
http://www.cinch.com/products/jones_plugs/series_2400/index.html
These would easily accept modern wire but all
joints are soldered. Further, there is no standard
retention feature to keep these connectors
mated and their insertion/removal forces are
rather light. However, a couple of wraps of
silicone rubber guide-line tape around the mated
pair would keep them secured together.
But again, unless you plan to routinely open wing
wiring bundles often as a matter of normal operation,
I think I would go to considerable effort to eliminate
connectors of any kind . . .
Bob . . .
Message 14
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--> AeroElectric-List message posted by: "Rob W M Shipley" <rob@robsglass.com>
I need some advice. I want to make sure my antennas are well matched to my radios
and with this in mind bought an Diamond SX20C SWR meter - recommended by a
local Ham radio shop. It seems useless with my Yaesu handheld unless I'm doing
something wrong since the cross needles barely move when I try it with the
rubber ducky antenna.
Is it going to give me useful results with a real antenna and a panel mount radio
or do I need to return this and try and get something else.
Published specs
Frequency range 3.5 - 150MHz
Input impedance 50 ohm
Power range 30w or 300w (switched)
Min power equirement 3w
The Yaesu Aviator Pilot is rated at 4w output.
Help and advice much appreciated.
Rob
Rob W M Shipley
RV9A N919RV (res) Fuselage
Message 15
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| Subject: | Carling LT series of toggle switches |
--> AeroElectric-List message posted by: Charlie Kuss <chaskuss@bellsouth.net>
Bob & listers,
I would like to use illuminated toggle switches in my RV8A project. I enjoy night
flying. I know that you feel that Carling makes a good product. I see that
B&C carries some of their products. Would the LT class of switches be suitable
for a OBAM aircraft? See:
http://www.carlingtech.com/pdf/s_lt.pdf
Is there another company who might make a better and reasonably priced product
of this class?
Charlie Kuss
RV-8A cockpit systems stuff
Planning my electrical system
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