AeroElectric-List Digest Archive

Wed 05/23/07


Total Messages Posted: 18



Today's Message Index:
----------------------
 
     1. 04:47 AM - Re: High VSWR reading on my antenna lead (Robert Feldtman)
     2. 05:46 AM - Re: Can Rotax be self exciting? (Robert L. Nuckolls, III)
     3. 05:57 AM - Re: High VSWR reading on my antenna lead (Kevin Horton)
     4. 06:07 AM - Re: Ni-Cad Capacity check (Robert L. Nuckolls, III)
     5. 06:16 AM - Re: High VSWR reading on my antenna lead (Alan Adamson)
     6. 06:18 AM - Re: High VSWR reading on my antenna lead (luckymacy@comcast.net (lucky))
     7. 06:25 AM - Re: Ni-Cad Capacity check (Christopher Stone)
     8. 07:10 AM - Re: High VSWR reading on my antenna lead (Robert L. Nuckolls, III)
     9. 07:45 AM - Re: High VSWR reading on my antenna lead (Rob Turk)
    10. 08:03 AM - Re: Odessey Battery Capacity Test (Tinne maha)
    11. 08:12 AM - Re: Dual circuit for J3300 EFI (Robert L. Nuckolls, III)
    12. 09:35 AM - Off Topic- Was : Re: We can't build our own avionics (John Burnaby)
    13. 10:07 AM - Re: Off Topic- Was : Re: We can't build our own avionics (Hinde, Frank George (Corvallis))
    14. 10:26 AM - Re: Off Topic- Was : Re: We can't build our own avionics (Walter Fellows)
    15. 10:59 AM - Re: Off Topic- Was : Re: We can't build our own avionics (Ernest Christley)
    16. 11:27 AM - Blowing fuses (Glaeser, Dennis A)
    17. 12:31 PM - Re: Wiring Diag for GTX327 (Norman Stapelberg)
    18. 03:04 PM - Re: Dual circuit for J3300 EFI (Peter Harris)
 
 
 


Message 1


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    Time: 04:47:17 AM PST US
    From: "Robert Feldtman" <bobf@feldtman.com>
    Subject: Re: High VSWR reading on my antenna lead
    borrow a known good meter from a ham in the area. make sure you set the forward power to exactly full deflection, then read the reflected power. you may have the gain set way too high. If it is 9 to one the radio would have detected this on it's own and decreased the power. I suspect the meter is bad or you don't have it adjusted right. get a ham to help you. Don't spend more money - get a ham to help you bobf W5RF and glastar owner ps - don't do it in the hangar - too much metal. roll it outside away from the hanger more than 30 feet or so On 5/22/07, James Beeghly <jbeeghly@earthlink.net> wrote: > > In the process of building up the avionics for our Wag Aero Super Sport I > reached that point where I was ready to power up the used King KY 97A Comm. > I had fabricated about a 10 - 12 foot long antenna lead using RG-400 and > BNC connectors purchased from B&C (and assembled with a RCT-2 coax crimping > tool also from B&C) to connect the comm to a used Cessna antenna (came from > a 172.) I plugged in the headset, turned on the radio, and all seemed well. > I listened (from inside the hanger) to airport traffic. I briefly keyed > the mike and heard myself on the scanner across the hanger. > > Then I turned off the radio and connected a DAIWA CN 720B SWR meter in the > antenna circuit. this involved undoing the BNC connector from the back of > the tray (The tray itself is fitted with a bulkhead type of female BNC > connector so this was no problem.) The 720 B is a cross needle meter rated > up to 150 MHz and with a 5 watt range at the lower end. It has two SO-239 > connectors on the back, one marked antenna and one transmitter. I had > gotten converters to use BNC connectors and had purchased a radio shack > premade RG-58 cable, about 6 feet long, to patch the meter to the radio. > The antenna lead connected to the Antenna connector on the 720 B. > > My understanding (I bought this meter on E-bay and do not yet have a > manual - one is ordered) is that reading VSWR is a matter of pushing > transmit and finding the VSWR line corresponding to where the two needles > intersect as they measure forward and reflected watts. If this is correct, > my system has a VSWR of 9 or 10. Needless to say, I did not hold the > transmit button down for long. > > I know that I am looking for a VSWR as close to 1 as possible, so this is > not acceptable. I don't quite know what to do next. I do not see a way to > calibrate the meter. My understanding is that this kind of meter is not > supposed to need calibration. I do not see what I could have done wrong in > constructing the antenna lead to get this kind of VSWR. > > I did try another experiment. I took my JVC handheld, and put the meter > between it and the whip antenna. There was barely enough power to read > VSWR, but it was still in the 9 or 10 range. I then measured VSWR using the > JVC feeding the antenna lead and Cessna antenna. The reading for forward > power was clearly improved, but the VSWR was still at the same high level. > These results make me wonder if there isn't something wrong with the meter > (or my measuring technique.) > > Does anyone have any suggestions for what to consider next? As you can no > doubt tell, I am new to this. Thanks. > > Jim Beeghly > > * > > > * > >


    Message 2


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    Time: 05:46:27 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: Re: Can Rotax be self exciting?
    At 06:14 AM 5/23/2007 +0000, you wrote: > >Could Z-16 (Rotax 912/914 System) incorporate self excitation feature as >seen in Z25 (note 25) and be self exciting and maintain overvoltage >protection? > >Thx. >Ron Parigoris Probably. But this is based on a schematic deduced by individuals who disassembled a Ducati regulator. The regulator topology is very close to that of the regulator sold by B&C so assuming that our presumptions are accurate and that the diagram has not changed, the answer would be yes. Bottom line is that the repeatable experiment rules. Try it, see what results you get and then let us know one way or another. Bob . . .


    Message 3


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    Time: 05:57:27 AM PST US
    From: Kevin Horton <khorton01@rogers.com>
    Subject: Re: High VSWR reading on my antenna lead
    Will a VSWR meter designed for the ham radio band produce valid results with aviation Com frequencies? Kevin Horton On Wed, 23 May 2007 06:45:39 -0500 "Robert Feldtman" <bobf@feldtman.com> wrote: > borrow a known good meter from a ham in the area. make sure you set the > forward power to exactly full deflection, then read the reflected power. you > may have the gain set way too high. If it is 9 to one the radio would have > detected this on it's own and decreased the power. I suspect the meter is > bad or you don't have it adjusted right. get a ham to help you. Don't spend > more money - get a ham to help you > > bobf > W5RF and glastar owner > > ps - don't do it in the hangar - too much metal. roll it outside away from > the hanger more than 30 feet or so > > On 5/22/07, James Beeghly <jbeeghly@earthlink.net> wrote: > > > > In the process of building up the avionics for our Wag Aero Super Sport I > > reached that point where I was ready to power up the used King KY 97A Comm. > > I had fabricated about a 10 - 12 foot long antenna lead using RG-400 and > > BNC connectors purchased from B&C (and assembled with a RCT-2 coax crimping > > tool also from B&C) to connect the comm to a used Cessna antenna (came from > > a 172.) I plugged in the headset, turned on the radio, and all seemed well. > > I listened (from inside the hanger) to airport traffic. I briefly keyed > > the mike and heard myself on the scanner across the hanger. > > > > Then I turned off the radio and connected a DAIWA CN 720B SWR meter in the > > antenna circuit. this involved undoing the BNC connector from the back of > > the tray (The tray itself is fitted with a bulkhead type of female BNC > > connector so this was no problem.) The 720 B is a cross needle meter rated > > up to 150 MHz and with a 5 watt range at the lower end. It has two SO-239 > > connectors on the back, one marked antenna and one transmitter. I had > > gotten converters to use BNC connectors and had purchased a radio shack > > premade RG-58 cable, about 6 feet long, to patch the meter to the radio. > > The antenna lead connected to the Antenna connector on the 720 B. > > > > My understanding (I bought this meter on E-bay and do not yet have a > > manual - one is ordered) is that reading VSWR is a matter of pushing > > transmit and finding the VSWR line corresponding to where the two needles > > intersect as they measure forward and reflected watts. If this is correct, > > my system has a VSWR of 9 or 10. Needless to say, I did not hold the > > transmit button down for long. > > > > I know that I am looking for a VSWR as close to 1 as possible, so this is > > not acceptable. I don't quite know what to do next. I do not see a way to > > calibrate the meter. My understanding is that this kind of meter is not > > supposed to need calibration. I do not see what I could have done wrong in > > constructing the antenna lead to get this kind of VSWR. > > > > I did try another experiment. I took my JVC handheld, and put the meter > > between it and the whip antenna. There was barely enough power to read > > VSWR, but it was still in the 9 or 10 range. I then measured VSWR using the > > JVC feeding the antenna lead and Cessna antenna. The reading for forward > > power was clearly improved, but the VSWR was still at the same high level. > > These results make me wonder if there isn't something wrong with the meter > > (or my measuring technique.) > > > > Does anyone have any suggestions for what to consider next? As you can no > > doubt tell, I am new to this. Thanks. > > > > Jim Beeghly > > > > * > > > > > > * > > > > >


    Message 4


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    Time: 06:07:29 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: Re: Ni-Cad Capacity check
    At 08:33 PM 5/22/2007 -0500, you wrote: > >Does anyone have a schematic for a capacity checker for small batteries like >Ni-Cads, etc. I have a product under development that will do the task you're asking about. It's a 2.5 x 4 inch etched circuit board offered in three versions. They hold 4AA, 2AA-2AAA or 4AAA cells and runs them down under a fixed loading condition. When discharge is completed, the time that each cell supported its load is reported by means of voltage readings taken with your shop mulitimeter. This device will be offered on my website for about $40. In the mean time, you might consider this product: http://westmountainradio.com/CBA_ham.htm I have one of these and find it quite useful in a variety of battery studies. It's also been used to measure and plot data (voltage vs. time) for the evaluation of a number of battery chargers. See this example: http://www.aeroelectric.com/Pictures/Curves/schumacher_3.jpg In terms of it's utility and versatility, the West Mountain Radio product is well worth the money. It's flexibility allows testing of any cells or array of cells over discharge current ranges of many amps down to tens of milliamps. Finally, the task is simple but the implementation for a roll-yer-own cap-meter is $time$ consuming. The goal is to craft a device that applies a load and records the time that a cell supports that load. My personal preference for mulit-cell evaluation uses a data acquisition module from Weeder Technology analog data input module http://www.weedtech.com/wtadc-m.pdf teamed with a computer running a Basic program that measures and records data with respect to time for later analysis. This is the technique used for crafting the article at: http://www.aeroelectric.com/articles/AA_Bat_Test.pdf . . . except that the data acquisition module used in this test was different than the device suggested above. The minimum $time$ route is the West Mountain Radio product with the AEC cap meter coming in second place. But if you'd like to acquire some REAL number gathering capabilities for both battery testing and a host of other applications, the Weeder Tech/Junk Computer approach offers a ton of capability for a very low investment. Bob . . . ---------------------------------------- ( "Physics is like sex: sure, it may ) ( give some practical results, but ) ( that's not why we do it." ) ( ) ( Richard P. Feynman ) ----------------------------------------


    Message 5


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    Time: 06:16:51 AM PST US
    From: "Alan Adamson" <aadamson@highrf.com>
    Subject: High VSWR reading on my antenna lead
    Kevin, the Ham Radio *band*, is a very large frequency spectrum :).... However, something designed for VHF and in Ham Speak, 2 meters, will work just fine. As a side note. Most SWR meters are DC-Daylite and should work just fine. There are units like a "bird wattmeter" that have specific "slugs" for specific power settings and frequencies, but if you have an SWR meter that simply measures forward and reverse power, you should be fine. Alan -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Kevin Horton Sent: Wednesday, May 23, 2007 8:56 AM Subject: Re: AeroElectric-List: High VSWR reading on my antenna lead --> <khorton01@rogers.com> Will a VSWR meter designed for the ham radio band produce valid results with aviation Com frequencies? Kevin Horton On Wed, 23 May 2007 06:45:39 -0500 "Robert Feldtman" <bobf@feldtman.com> wrote: > borrow a known good meter from a ham in the area. make sure you set > the forward power to exactly full deflection, then read the reflected > power. you may have the gain set way too high. If it is 9 to one the > radio would have detected this on it's own and decreased the power. I > suspect the meter is bad or you don't have it adjusted right. get a > ham to help you. Don't spend more money - get a ham to help you > > bobf > W5RF and glastar owner > > ps - don't do it in the hangar - too much metal. roll it outside away > from the hanger more than 30 feet or so > > On 5/22/07, James Beeghly <jbeeghly@earthlink.net> wrote: > > > > In the process of building up the avionics for our Wag Aero Super > > Sport I reached that point where I was ready to power up the used King KY 97A Comm. > > I had fabricated about a 10 - 12 foot long antenna lead using > > RG-400 and BNC connectors purchased from B&C (and assembled with a > > RCT-2 coax crimping tool also from B&C) to connect the comm to a > > used Cessna antenna (came from a 172.) I plugged in the headset, turned on the radio, and all seemed well. > > I listened (from inside the hanger) to airport traffic. I briefly > > keyed the mike and heard myself on the scanner across the hanger. > > > > Then I turned off the radio and connected a DAIWA CN 720B SWR meter > > in the antenna circuit. this involved undoing the BNC connector > > from the back of the tray (The tray itself is fitted with a bulkhead > > type of female BNC connector so this was no problem.) The 720 B is a > > cross needle meter rated up to 150 MHz and with a 5 watt range at > > the lower end. It has two SO-239 connectors on the back, one marked > > antenna and one transmitter. I had gotten converters to use BNC > > connectors and had purchased a radio shack premade RG-58 cable, about 6 feet long, to patch the meter to the radio. > > The antenna lead connected to the Antenna connector on the 720 B. > > > > My understanding (I bought this meter on E-bay and do not yet have a > > manual - one is ordered) is that reading VSWR is a matter of pushing > > transmit and finding the VSWR line corresponding to where the two > > needles intersect as they measure forward and reflected watts. If > > this is correct, my system has a VSWR of 9 or 10. Needless to say, > > I did not hold the transmit button down for long. > > > > I know that I am looking for a VSWR as close to 1 as possible, so > > this is not acceptable. I don't quite know what to do next. I do > > not see a way to calibrate the meter. My understanding is that this kind of meter is not > > supposed to need calibration. I do not see what I could have done wrong in > > constructing the antenna lead to get this kind of VSWR. > > > > I did try another experiment. I took my JVC handheld, and put the > > meter between it and the whip antenna. There was barely enough > > power to read VSWR, but it was still in the 9 or 10 range. I then > > measured VSWR using the JVC feeding the antenna lead and Cessna > > antenna. The reading for forward power was clearly improved, but the VSWR was still at the same high level. > > These results make me wonder if there isn't something wrong with the > > meter (or my measuring technique.) > > > > Does anyone have any suggestions for what to consider next? As you > > can no doubt tell, I am new to this. Thanks. > > > > Jim Beeghly > > > > * > > > > > > * > > > > >


    Message 6


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    Time: 06:18:50 AM PST US
    From: luckymacy@comcast.net (lucky)
    Subject: Re: High VSWR reading on my antenna lead
    Worked for us. Exact numbers are going to be incorrect but the relative deflection is still valid. ie, it will still read toward the "bad" end if there's a lot of reflection and read more towards the "good" end of the scale after you fix a problem but won't tell you just how good your SWR really is if you are anal about your exact number... -------------- Original message -------------- From: Kevin Horton <khorton01@rogers.com> > > Will a VSWR meter designed for the ham radio band produce valid results with > aviation Com frequencies? > > Kevin Horton > > On Wed, 23 May 2007 06:45:39 -0500 > "Robert Feldtman" wrote: > > > borrow a known good meter from a ham in the area. make sure you set the > > forward power to exactly full deflection, then read the reflected power. you > > may have the gain set way too high. If it is 9 to one the radio would have > > detected this on it's own and decreased the power. I suspect the meter is > > bad or you don't have it adjusted right. get a ham to help you. Don't spend > > more money - get a ham to help you > > > > bobf > > W5RF and glastar owner > > > > ps - don't do it in the hangar - too much metal. roll it outside away from > > the hanger more than 30 feet or so > > > > On 5/22/07, James Beeghly wrote: > > > > > > In the process of building up the avionics for our Wag Aero Super Sport I > > > reached that point where I was ready to power up the used King KY 97A Comm. > > > I had fabricated about a 10 - 12 foot long antenna lead using RG-400 and > > > BNC connectors purchased from B&C (and assembled with a RCT-2 coax crimping > > > tool also from B&C) to connect the comm to a used Cessna antenna (came from > > > a 172.) I plugged in the headset, turned on the radio, and all seemed well. > > > I listened (from inside the hanger) to airport traffic. I briefly keyed > > > the mike and heard myself on the scanner across the hanger. > > > > > > Then I turned off the radio and connected a DAIWA CN 720B SWR meter in the > > > antenna circuit. this involved undoing the BNC connector from the back of > > > the tray (The tray itself is fitted with a bulkhead type of female BNC > > > connector so this was no problem.) The 720 B is a cross needle meter rated > > > up to 150 MHz and with a 5 watt range at the lower end. It has two SO-239 > > > connectors on the back, one marked antenna and one transmitter. I had > > > gotten converters to use BNC connectors and had purchased a radio shack > > > premade RG-58 cable, about 6 feet long, to patch the meter to the radio. > > > The antenna lead connected to the Antenna connector on the 720 B. > > > > > > My understanding (I bought this meter on E-bay and do not yet have a > > > manual - one is ordered) is that reading VSWR is a matter of pushing > > > transmit and finding the VSWR line corresponding to where the two needles > > > intersect as they measure forward and reflected watts. If this is correct, > > > my system has a VSWR of 9 or 10. Needless to say, I did not hold the > > > transmit button down for long. > > > > > > I know that I am looking for a VSWR as close to 1 as possible, so this is > > > not acceptable. I don't quite know what to do next. I do not see a way to > > > calibrate the meter. My understanding is that this kind of meter is not > > > supposed to need calibration. I do not see what I could have done wrong in > > > constructing the antenna lead to get this kind of VSWR. > > > > > > I did try another experiment. I took my JVC handheld, and put the meter > > > between it and the whip antenna. There was barely enough power to read > > > VSWR, but it was still in the 9 or 10 range. I then measured VSWR using the > > > JVC feeding the antenna lead and Cessna antenna. The reading for forward > > > power was clearly improved, but the VSWR was still at the same high level. > > > These results make me wonder if there isn't something wrong with the meter > > > (or my measuring technique.) > > > > > > Does anyone have any suggestions for what to consider next? As you can no > > > doubt tell, I am new to this. Thanks. > > > > > > Jim Beeghly > > > > > > * > > > > > > > > > * > > > > > > > > > > > > <html><body> <DIV>Worked for us. Exact numbers are going to be incorrect but the relative deflection is still valid.&nbsp; ie, &nbsp;it will still read&nbsp;toward the "bad"&nbsp;end&nbsp;if there's a lot of reflection and read more towards the "good" end of the scale&nbsp;after you fix a&nbsp;problem&nbsp;but won't tell you just how good your SWR really is&nbsp;if you are anal about your exact number...</DIV> <DIV>&nbsp;</DIV> <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid">-------------- Original message -------------- <BR>From: Kevin Horton &lt;khorton01@rogers.com&gt; <BR><BR>&gt; --&gt; AeroElectric-List message posted by: Kevin Horton <KHORTON01@ROGERS.COM><BR>&gt; <BR>&gt; Will a VSWR meter designed for the ham radio band produce valid results with <BR>&gt; aviation Com frequencies? <BR>&gt; <BR>&gt; Kevin Horton <BR>&gt; <BR>&gt; On Wed, 23 May 2007 06:45:39 -0500 <BR>&gt; "Robert Feldtman" <BOBF@FELDTMAN.COM>wrote: <BR>&gt; <BR>&gt; &gt; borrow a known good meter from a ham in the area. make sure you set the <BR>&gt; &gt; forward power to exactly full deflection, then read the reflected power. you <BR>&gt; &gt; may have the gain set way too high. If it is 9 to one the radio would have <BR>&gt; &gt; detected this on it's own and decreased the power. I suspect the meter is <BR>&gt; &gt; bad or you don't have it adjusted right. get a ham to help you. Don 't spe nd <BR>&gt; &gt; more money - get a ham to help you <BR>&gt; &gt; <BR>&gt; &gt; bobf <BR>&gt; &gt; W5RF and glastar owner <BR>&gt; &gt; <BR>&gt; &gt; ps - don't do it in the hangar - too much metal. roll it outside away from <BR>&gt; &gt; the hanger more than 30 feet or so <BR>&gt; &gt; <BR>&gt; &gt; On 5/22/07, James Beeghly <JBEEGHLY@EARTHLINK.NET>wrote: <BR>&gt; &gt; &gt; <BR>&gt; &gt; &gt; In the process of building up the avionics for our Wag Aero Super Sport I <BR>&gt; &gt; &gt; reached that point where I was ready to power up the used King KY 97A Comm. <BR>&gt; &gt; &gt; I had fabricated about a 10 - 12 foot long antenna lead using RG-400 and <BR>&gt; &gt; &gt; BNC connectors purchased from B&amp;C (and assembled with a RCT-2 coax crimping <BR>&gt; &gt; &gt; tool also from B&amp;C) to connect the comm to a used Cessna antenna (came from <BR>&gt; &gt; &gt; a 172.) I plugged in the headset, turned on the radio, and all seemed well. <BR>&gt; &gt; &gt; I listened (from ins ide th e hanger) to airport traffic. I briefly keyed <BR>&gt; &gt; &gt; the mike and heard myself on the scanner across the hanger. <BR>&gt; &gt; &gt; <BR>&gt; &gt; &gt; Then I turned off the radio and connected a DAIWA CN 720B SWR meter in the <BR>&gt; &gt; &gt; antenna circuit. this involved undoing the BNC connector from the back of <BR>&gt; &gt; &gt; the tray (The tray itself is fitted with a bulkhead type of female BNC <BR>&gt; &gt; &gt; connector so this was no problem.) The 720 B is a cross needle meter rated <BR>&gt; &gt; &gt; up to 150 MHz and with a 5 watt range at the lower end. It has two SO-239 <BR>&gt; &gt; &gt; connectors on the back, one marked antenna and one transmitter. I had <BR>&gt; &gt; &gt; gotten converters to use BNC connectors and had purchased a radio shack <BR>&gt; &gt; &gt; premade RG-58 cable, about 6 feet long, to patch the meter to the radio. <BR>&gt; &gt; &gt; The antenna lead connected to the Antenna connector on the 720 B. <BR>&gt; &gt; &gt; <BR>&g t; &gt ; &gt; My understanding (I bought this meter on E-bay and do not yet have a <BR>&gt; &gt; &gt; manual - one is ordered) is that reading VSWR is a matter of pushing <BR>&gt; &gt; &gt; transmit and finding the VSWR line corresponding to where the two needles <BR>&gt; &gt; &gt; intersect as they measure forward and reflected watts. If this is correct, <BR>&gt; &gt; &gt; my system has a VSWR of 9 or 10. Needless to say, I did not hold the <BR>&gt; &gt; &gt; transmit button down for long. <BR>&gt; &gt; &gt; <BR>&gt; &gt; &gt; I know that I am looking for a VSWR as close to 1 as possible, so this is <BR>&gt; &gt; &gt; not acceptable. I don't quite know what to do next. I do not see a way to <BR>&gt; &gt; &gt; calibrate the meter. My understanding is that this kind of meter is not <BR>&gt; &gt; &gt; supposed to need calibration. I do not see what I could have done wrong in <BR>&gt; &gt; &gt; constructing the antenna lead to get this kind of VSWR. <BR>&gt; &gt; &gt; <BR>&gt; &gt; &gt ; I di ===== <pre><b><font size=2 color="#000000" face="courier new,courier"> </b></font></pre></body></html>


    Message 7


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    Time: 06:25:24 AM PST US
    From: Christopher Stone <rv8iator@earthlink.net>
    Subject: Re: Ni-Cad Capacity check
    > >> >>Does anyone have a schematic for a capacity checker for small batteries like >>Ni-Cads, etc. > >Here is a link to a NiCad/NiMh capacity tester. Not as capable as the West Mountain product but less money and self contained. I have used the tester and it performs as advertised. http://www.siriuselectronics.com/index.php?main_page=product_info&cPath=1&products_id=123 Chris Stone


    Message 8


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    Time: 07:10:17 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: Re: High VSWR reading on my antenna lead
    At 08:55 AM 5/23/2007 -0400, you wrote: > >Will a VSWR meter designed for the ham radio band produce valid results >with aviation Com frequencies? > >Kevin Horton Some do, some don't. I recall a lot of wasted $time$ many moons ago when building a new colinear array for use on our repeater installation at the 1200 foot platform of KTVH in Hutchinson KS. See: http://www.aeroelectric.com/Pictures/Misc/KTVH.gif Glen Brasch and I worked for several days bending aluminum drilling brackets, bolting elements and cutting coax for the feedline transformers. Each step of the way was checked with a reflectometer style SWR meter . . . http://www.aeroelectric.com/Pictures/Tools/SWR/SWR_Sometimes_4.jpg http://en.wikipedia.org/wiki/SWR_meter . . . and we thought we were doing really good work as each step of the process produced an excellent SWR reading. Imagine our dismay when the assembled array tested with anther meter ( A Bird Model 43) http://www.aeroelectric.com/Pictures/Tools/Bird_43.jpg called it less than the best we should expect. Bottom line is that there are easy mistakes to be made in the design and assembly of many test instruments with those crafted for use at high RF frequencies being strong candidates for obtuse behavior. Just 'cause the label says so don't make it so. I dumped my $low$ reflectometer in the trash and bought a Bird. If it's important to know what the numbers are, its a safe bet to go with the repeatable experiments like Tektronix, HP, Bird, Fluke, etc. This doesn't mean you can't find good value in other brands . . . but if there is doubt and the expenditure of $time$ is a critical part of your efforts, the repeatable experiments are often the most economical choices in spite of their higher prices off-the-shelf. Here's a montage of examples for repeatable experiments -AND- experiments to be tested for repeatability in the world of RF instrumentation . . . http://www.aeroelectric.com/Pictures/Tools/SWR/ Bob . . .


    Message 9


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    Time: 07:45:27 AM PST US
    From: "Rob Turk" <matronics@rtist.nl>
    Subject: Re: High VSWR reading on my antenna lead
    That depends on the frequency range it's designed for. If it's for 0-30MHz (most el-cheapo VSWR's and CB stuff) then there's a big chance that it won't work. If you get one designed for 2m (144-148MHz) then you should have no problems gettng an accurate VSWR reading. Power readings will most likely be unreliable though, except if you use something professional like the Bird model that Bob mentioned. Rob ----- Original Message ----- From: "Kevin Horton" <khorton01@rogers.com> Sent: Wednesday, May 23, 2007 2:55 PM Subject: Re: AeroElectric-List: High VSWR reading on my antenna lead > <khorton01@rogers.com> > > Will a VSWR meter designed for the ham radio band produce valid results > with aviation Com frequencies? > > Kevin Horton > > On Wed, 23 May 2007 06:45:39 -0500 > "Robert Feldtman" <bobf@feldtman.com> wrote: > >> borrow a known good meter from a ham in the area. make sure you set the >> forward power to exactly full deflection, then read the reflected power. >> you >> may have the gain set way too high. If it is 9 to one the radio would >> have >> detected this on it's own and decreased the power. I suspect the meter is >> bad or you don't have it adjusted right. get a ham to help you. Don't >> spend >> more money - get a ham to help you >> >> bobf >> W5RF and glastar owner >> >> ps - don't do it in the hangar - too much metal. roll it outside away >> from >> the hanger more than 30 feet or so >> >> On 5/22/07, James Beeghly <jbeeghly@earthlink.net> wrote: >> > >> > In the process of building up the avionics for our Wag Aero Super Sport >> > I >> > reached that point where I was ready to power up the used King KY 97A >> > Comm. >> > I had fabricated about a 10 - 12 foot long antenna lead using RG-400 >> > and >> > BNC connectors purchased from B&C (and assembled with a RCT-2 coax >> > crimping >> > tool also from B&C) to connect the comm to a used Cessna antenna (came >> > from >> > a 172.) I plugged in the headset, turned on the radio, and all seemed >> > well. >> > I listened (from inside the hanger) to airport traffic. I briefly >> > keyed >> > the mike and heard myself on the scanner across the hanger. >> > >> > Then I turned off the radio and connected a DAIWA CN 720B SWR meter in >> > the >> > antenna circuit. this involved undoing the BNC connector from the back >> > of >> > the tray (The tray itself is fitted with a bulkhead type of female BNC >> > connector so this was no problem.) The 720 B is a cross needle meter >> > rated >> > up to 150 MHz and with a 5 watt range at the lower end. It has two >> > SO-239 >> > connectors on the back, one marked antenna and one transmitter. I had >> > gotten converters to use BNC connectors and had purchased a radio shack >> > premade RG-58 cable, about 6 feet long, to patch the meter to the >> > radio. >> > The antenna lead connected to the Antenna connector on the 720 B. >> > >> > My understanding (I bought this meter on E-bay and do not yet have a >> > manual - one is ordered) is that reading VSWR is a matter of pushing >> > transmit and finding the VSWR line corresponding to where the two >> > needles >> > intersect as they measure forward and reflected watts. If this is >> > correct, >> > my system has a VSWR of 9 or 10. Needless to say, I did not hold the >> > transmit button down for long. >> > >> > I know that I am looking for a VSWR as close to 1 as possible, so this >> > is >> > not acceptable. I don't quite know what to do next. I do not see a >> > way to >> > calibrate the meter. My understanding is that this kind of meter is >> > not >> > supposed to need calibration. I do not see what I could have done >> > wrong in >> > constructing the antenna lead to get this kind of VSWR. >> > >> > I did try another experiment. I took my JVC handheld, and put the >> > meter >> > between it and the whip antenna. There was barely enough power to read >> > VSWR, but it was still in the 9 or 10 range. I then measured VSWR >> > using the >> > JVC feeding the antenna lead and Cessna antenna. The reading for >> > forward >> > power was clearly improved, but the VSWR was still at the same high >> > level. >> > These results make me wonder if there isn't something wrong with the >> > meter >> > (or my measuring technique.) >> > >> > Does anyone have any suggestions for what to consider next? As you can >> > no >> > doubt tell, I am new to this. Thanks. >> > >> > Jim Beeghly >> > >> > * >> > >> > >> > * >> > >> > >> > > >


    Message 10


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    Time: 08:03:25 AM PST US
    From: "Tinne maha" <tinnemaha@hotmail.com>
    Subject: Re: Odessey Battery Capacity Test
    I don't get it...........I thought the purpose of the capacity test was to see how long the ship's battery could power the essential bus & stay above 10.5 Volts. If the amount of time this takes is within the pilot's zone of comfort (i.e. enough to land safely), then the battery is deemed sufficient. Any battery's ability to start an engine is tested at each startup. Assuming the above is true, I don't see what this particular test accomplished. Can someone explain what I'm missing? Thanks, Grant Time: 03:35:28 PM PST US From: Charles Brame <chasb@satx.rr.com> Subject: AeroElectric-List: Odessey Battery Capacity Test Based on the recent discussions of battery capacity, I decided to put my six year old Odessey PC-680 battery through a poor man's capacity test. I started with a fully charged battery which read 12.7 volts at the beginning of the test. I turned on my aircraft main bus with all the avionics, gyros, engine monitor (VM-1000), instruments, and instrument lights - ON. The electronic ignition, nav lights, and strobes were left OFF (aircraft on the ground.) After 20 minutes the voltage was down to 12.1 volts. The engine was then started (cold start and it took two tries to get it going.) The electronic ignition and electric boost pump were turned ON; however, the alternator was intentionally left OFF. The engine was run for three or four minutes and shut down. The aircraft then sat for another 35 minutes with the main bus, avionics, etc., left ON though the ignition and boost pump were turned OFF. The lowest battery voltage was 11.4 volts. After a full hour of battery only operation, the engine was again started with no problems. The alternator was turned on after the second engine start and the bus voltage read 13.8. (I forgot to check the amperage, which is basically an alternator loadmeter.) The engine was only run for about three minutes. After engine shutdown, the battery voltage was back up to 12.4 and the test ended. Pretty good battery I think. Based on the age of my PC-680, I really didn't expect this kind of performance. Charlie Brame RV-6A N11CB San Antonio _________________________________________________________________ More photos, more messages, more storageget 2GB with Windows Live Hotmail.


    Message 11


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    Time: 08:12:06 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: Re: Dual circuit for J3300 EFI
    It would be MUCH faster if you could sketch your changes for scanning and posting to the List. I'm not sure the images in my head based on your words match the reality of your proposal. Bob . . . At 03:05 PM 5/23/2007 +1000, you wrote: > > >First a big thank you Bob for the PM self exciting feature and the crowbar >CB tripper. Watching the voltmeter stay up, and running the electronic >ignition all with the master switch off was too much and I had to go home >and have a couple of beers to celebrate it. Clever stuff. > >I have been finishing installation of a dual circuit based on Z-21A but I >have wandered astray a bit as follows: > > >1. Re Z21-A I have connected the starter relay direct to the >battery and not via the battery contactor. I am using the battery >contactor only to interrupt the charging current (and to close the >alternator relay.) I did this only because I do not know the logic for >running the starter current through two series relays ? > >2. I have retained the DPST master switch to isolate battery from >alternator from main bus. This master connects the battery contactor which >connects the alternator relay and it connects the main bus. > >3. I have earthed the alternator relay coil and action it from the >master switch through the battery contactor. I was thinking that the >current from a failed regulator will otherwise go to earth through the >master switch ? But how much current to expect here, I guess it is limited >by the coil resistance. The method I have used saves another wire routed >out to the engine bay. > >4. For the ebus I just had to use those two big diodes which >access either the battery or the alternator or both (normally both) each >with a green LED signal light. Z21-A offers power from battery plus >alternator , or from battery but can not be switched to run from >alternator only. So What ? Well it just appealed to me to be able to >choose which power source in any emergency and the green lights are a feel >good feature. > > >I am offering this amendment fully expecting a flame out and ready to eat >humble pie and learn some more, mean time I will stay off the beer. > >Circuit details follow : > >Peter > > >image002.jpg > > >incoming mail is certified Virus Free. >Checked by AVG. Bob . . . ---------------------------------------- ( "Physics is like sex: sure, it may ) ( give some practical results, but ) ( that's not why we do it." ) ( ) ( Richard P. Feynman ) ----------------------------------------


    Message 12


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    Time: 09:35:45 AM PST US
    From: "John Burnaby" <jonlaury@impulse.net>
    Subject: Re: Off Topic- Was : Re: We can't build our own avionics
    Despite the dearth of applicable information for homebuilders in SA, and that AOPA Pilot unabashedly promotes trainer aircraft that cost more than my house, I still pay my dues to support the EAA and AOPA. I do this because general aviation is under assault on myriad fronts. The public perception of private aircraft is one of exclusivity, an arena reserved for the wealthy. Anything that excludes the lazy and unimaginative, that celebrates creativity, possibility and industry, is frightening to a lot of people because it challenges them to shut-off the TV and learn something. That takes effort and I think, unfortunately, most people don't want to stray very far from the comfort zone of what they know and repeat. It's easier to dismiss homebuilders and non-commercial pilots as crazy than to go to the airport and talk to one about flying and building. Inspite of the condescending, cornball, syrupy image of a family affair promoted by the EAA, I support the organization because I am convinced that private aviation and legal homebuilding would simply vanish without the cumulative efforts of AOPA and EAA. The two organizations are microphones for a collective voice, amplifying the message of our passionate group. They are the glue that keeps our spinning, aviating world cohesive, staving off the centrifugal forces that would fragment us into meaningless pieces. Without them, I fear, the few letters that may arrive on congressional desks, supportive and protective of our passion, will be drowned in a tide seeking conformity and banality. So, I say send in your dues, and let the EAA and AOPA put on the smiley face and the suit that allows us to do the putative job of the EAA; experimenting, sharing information, camaraderie, and advancing aviation technology. Do not Archive


    Message 13


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    Time: 10:07:30 AM PST US
    Subject: Re: Off Topic- Was : Re: We can't build our own avionics
    From: "Hinde, Frank George (Corvallis)" <frank.hinde@hp.com>
    Excellent thoughts John, Yes I too support the AOPA for the same reason, sure they are "beating the beehive" with a big stick but if they didn't the airlines would just roll right over us with their user fees and we'd be grounded in short order. The sad thing is we may still loose but we're much stronger together and if AOPA gives us a voice in Washington then they are more than worth my $40. Frank Do not archive ________________________________ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of John Burnaby Sent: Wednesday, May 23, 2007 10:10 AM Subject: AeroElectric-List: Off Topic- Was : Re: We can't build our own avionics Despite the dearth of applicable information for homebuilders in SA, and that AOPA Pilot unabashedly promotes trainer aircraft that cost more than my house, I still pay my dues to support the EAA and AOPA. I do this because general aviation is under assault on myriad fronts. The public perception of private aircraft is one of exclusivity, an arena reserved for the wealthy. Anything that excludes the lazy and unimaginative, that celebrates creativity, possibility and industry, is frightening to a lot of people because it challenges them to shut-off the TV and learn something. That takes effort and I think, unfortunately, most people don't want to stray very far from the comfort zone of what they know and repeat. It's easier to dismiss homebuilders and non-commercial pilots as crazy than to go to the airport and talk to one about flying and building. Inspite of the condescending, cornball, syrupy image of a family affair promoted by the EAA, I support the organization because I am convinced that private aviation and legal homebuilding would simply vanish without the cumulative efforts of AOPA and EAA. The two organizations are microphones for a collective voice, amplifying the message of our passionate group. They are the glue that keeps our spinning, aviating world cohesive, staving off the centrifugal forces that would fragment us into meaningless pieces. Without them, I fear, the few letters that may arrive on congressional desks, supportive and protective of our passion, will be drowned in a tide seeking conformity and banality. So, I say send in your dues, and let the EAA and AOPA put on the smiley face and the suit that allows us to do the putative job of the EAA; experimenting, sharing information, camaraderie, and advancing aviation technology. Do not Archive


    Message 14


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    Time: 10:26:20 AM PST US
    From: "Walter Fellows" <walter.fellows@gmail.com>
    Subject: Re: Off Topic- Was : Re: We can't build our own avionics
    Very well said and I support both organizations. However I cannot help but feeling sad when a 130 page issue of SA contains only a few pages related to building as pointed out by Bob. On the bright side we would not have had this forum back in in good ol days when SA was mostly about building and SA never ever got into the aircraft electrical systems in the way this forum does. I would like to say thanks to Bob for that. Bob's remarks on Greg of BMA were appreciated as well, it is good to have multiple views eventhough the people expressing them might be a bit abrasive. On 5/23/07, John Burnaby <jonlaury@impulse.net> wrote: > > Despite the dearth of applicable information for homebuilders in SA, and > that AOPA Pilot unabashedly promotes trainer aircraft that cost more than my > house, I still pay my dues to support the EAA and AOPA. I do this because > general aviation is under assault on myriad fronts. The public > perception of private aircraft is one of exclusivity, an arena reserved for > the wealthy. Anything that excludes the lazy and unimaginative, that > celebrates creativity, possibility and industry, is frightening to a lot of > people because it challenges them to shut-off the TV and learn something. > That takes effort and I think, unfortunately, most people don't want to > stray very far from the comfort zone of what they know and repeat. It's > easier to dismiss homebuilders and non-commercial pilots as crazy than to go > to the airport and talk to one about flying and building. > Inspite of the condescending, cornball, syrupy image of a family affair > promoted by the EAA, I support the organization because I am convinced that > private aviation and legal homebuilding would simply vanish without the > cumulative efforts of AOPA and EAA. The two organizations are microphones > for a collective voice, amplifying the message of our passionate group. They > are the glue that keeps our spinning, aviating world cohesive, staving off > the centrifugal forces that would fragment us into > meaningless pieces. Without them, I fear, the few letters that may arrive on > congressional desks, supportive and protective of our passion, will be > drowned in a tide seeking conformity and banality. So, I say send in your > dues, and let the EAA and AOPA put on the smiley face and the suit that > allows us to do the putative job of the EAA; experimenting, sharing > information, camaraderie, and advancing aviation technology. > > Do not Archive > > * > > > * > >


    Message 15


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    Time: 10:59:22 AM PST US
    From: Ernest Christley <echristley@nc.rr.com>
    Subject: Re: Off Topic- Was : Re: We can't build our own avionics
    John Burnaby wrote: > Despite the dearth of applicable information for homebuilders in SA, > and that AOPA Pilot unabashedly promotes trainer aircraft that cost > more than my house, I still pay my dues to support the EAA and AOPA. I > do this because general aviation is under assault on myriad > fronts. The public perception of private aircraft is one of > exclusivity, an arena reserved for the wealthy. Anything that excludes > the lazy and unimaginative, that celebrates creativity, possibility > and industry, is frightening to a lot of people because it challenges > them to shut-off the TV and learn something. That takes effort and I > think, unfortunately, most people don't want to stray very far from > the comfort zone of what they know and repeat. It's easier to dismiss > homebuilders and non-commercial pilots as crazy than to go to the > airport and talk to one about flying and building. > Inspite of the condescending, cornball, syrupy image of a family > affair promoted by the EAA, I support the organization because I am > convinced that private aviation and legal homebuilding would simply > vanish without the cumulative efforts of AOPA and EAA. The two > organizations are microphones for a collective voice, amplifying the > message of our passionate group. They are the glue that keeps our > spinning, aviating world cohesive, staving off the centrifugal forces > that would fragment us into meaningless pieces. Without them, I fear, > the few letters that may arrive on congressional desks, supportive and > protective of our passion, will be drowned in a tide seeking > conformity and banality. So, I say send in your dues, and let the EAA > and AOPA put on the smiley face and the suit that allows us to do the > putative job of the EAA; experimenting, sharing information, > camaraderie, and advancing aviation technology. Good words, John. EAA and AOPA do provide necessary functions, but they will spin off into the mind-numbed, TV-viewing masses if we let them. The subject article being a prime example. The only response is to scream until the usurpers who would lead us down that path scurry back into their holes. I don't want to write a freakin' article. I want to build my airplane, and have EAA provide me with some help in that goal. That attitude places me dead square in the middle of the MTV generation. "My needs. My needs," I cry, along with the rest of the mind-numbed. And I'm not alone. Builder's everywhere are hunkered down in their garages, expecting someone else to look after their interests. But we can't do that. We all want a revolution, where the productive, intelligent, and demonstrably capable come out on top, but we want someone else to lead and fight the battles. That won't happen. The president of the organization has never built anything. The leadership can't find the funds to build a friggin' WIND TUNNEL, but there's cash enough to purchase and operate a P-51 for said president to have joy rides in. Meanwhile, has the CAFE Foundation done ANYTHING since getting a mogas STC for certified planes? These are not the priorities of experimenters trying to expand on the best we know how to do. You aren't fighting an organization of experimenters gone astray. You're fighting a rising wave of conformity and banality washing in from the outside and threatening to swamp us all. They try to tell us that the EAA has grown to be something larger than it used to be. I say that it has shrunk to be much less, nothing more than the Disneyland of airplanes. If we let the nonsense published in the subject article go unanswered, then our collective voice will be saying that we're not capable of building an entire airplane. We need to be circumvented and have artificial fences erected around us. It may be to late. The condescending cornballs may have won already, in which case legal homebuilding as we know it will eventually vanish. "Homebuilding" will amount to nothing more than showing up for a two week 'quick-build' vacation at a kit factory, where you install your selection of off the shelf components in a pre-molded shell of an aircraft. Of course, you can a Lindsy at a flyin, because you chose the best paint scheme from those available. Bob fought back till he lost interest. I know others who simply have no interest in such activities. However, I've generated a LOT of inter-activity in builders from my local chapter by just sending out a lunch invitation by email. If not for that interest, I'd drop my EAA membership this year. I have little more than a couple articles in me, but I'll give what I have. If the cornballs have won, I'll look to organize and join "HAA!" (Homebuilder's Aviation Alliance...we laugh at you!)


    Message 16


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    Time: 11:27:19 AM PST US
    Subject: Blowing fuses
    From: "Glaeser, Dennis A" <dennis.glaeser@eds.com>
    Bob, I'd asked this question a week ago and never got a reply that offered a plausible explanation, so I'm trying again... I have a Z-19 (2 batt, 1 alt) architecture, modified a bit for a Subaru engine, with rear mounted Odyssey batteries. I have 2 lighter receptacles on the panel, each wired to a battery hot bus through a 10a fuse. I attached a couple of lighter plugs on my Battery Tender Jr. as a convenient way to charge the batteries. The Problem: I can insert and remove a 'hot' charger plug to one battery at a time with no problem. However once I insert both plugs (and both batteries are charging), and then remove one plug, the fuse on the other circuit blows. This is a repeatable experiment. Once both plugs are inserted, the only way I can remove them is to either unplug the charger, or unplug the charging plugs from the charger (the output wire has a plug to enable different endings to be attached). Can you explain the physics of why the fuse blows when one plug is removed? Thanks, Dennis Glaeser RV-7A Rochester Hills, MI


    Message 17


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    Time: 12:31:48 PM PST US
    From: "Norman Stapelberg" <norshel@mweb.co.za>
    Subject: Wiring Diag for GTX327
    Thanks to all that responded I did not realise that it would be so simple. Thanks again Norman -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Gaye and Vaughn Sent: 22 May 2007 08:36 PM Subject: Re: AeroElectric-List: Wiring Diag for GTX327 <vaughnray@bvunet.net> Here is a link to the installation manual that I found.....Vaughn http://aviation.vortex.is/install/Garmin%20Install%20manuals/GTX-327.pdf ----- Original Message ----- From: "Norman Stapelberg" <norshel@mweb.co.za> Sent: Tuesday, May 22, 2007 1:29 PM Subject: AeroElectric-List: Wiring Diag for GTX327 > <norshel@mweb.co.za> > > I wonder if some could help out, I am busy fitting a Garmin GTX327 > Transponder in a friends plane, as luck would have it he has misplaced > the manuals I have managed to download the operation manual, but am some > what stuck for the wiring side. > > Thanks > > Norman Stapelberg > South Africa > RV7 Fuselage 50% > > >


    Message 18


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    Time: 03:04:59 PM PST US
    From: "Peter Harris" <peterjfharris@bigpond.com>
    Subject: Dual circuit for J3300 EFI
    Bob, Sorry about my attachment, the scan att is not accepted on the Yahoo lists I know best. I should correct item 3 below, pls disregard my reference to the coil resistance which is shunted by the crowbar, I hope that helps to make more sense? But I am curious to know how much current to expect through the crowbar if the regulator fails. I can still remember a boiling battery and think about the amount of energy to be wasted through the crowbar. Thanks, Peter -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Thursday, 24 May 2007 2:12 AM Subject: Re: AeroElectric-List: Dual circuit for J3300 EFI It would be MUCH faster if you could sketch your changes for scanning and posting to the List. I'm not sure the images in my head based on your words match the reality of your proposal. Bob . . . At 03:05 PM 5/23/2007 +1000, you wrote: > > >First a big thank you Bob for the PM self exciting feature and the crowbar >CB tripper. Watching the voltmeter stay up, and running the electronic >ignition all with the master switch off was too much and I had to go home >and have a couple of beers to celebrate it. Clever stuff. > >I have been finishing installation of a dual circuit based on Z-21A but I >have wandered astray a bit as follows: > > >1. Re Z21-A I have connected the starter relay direct to the >battery and not via the battery contactor. I am using the battery >contactor only to interrupt the charging current (and to close the >alternator relay.) I did this only because I do not know the logic for >running the starter current through two series relays ? > >2. I have retained the DPST master switch to isolate battery from >alternator from main bus. This master connects the battery contactor which >connects the alternator relay and it connects the main bus. > >3. I have earthed the alternator relay coil and action it from the >master switch through the battery contactor. I was thinking that the >current from a failed regulator will otherwise go to earth through the >master switch ? But how much current to expect here, I guess it is limited >by the coil resistance. The method I have used saves another wire routed >out to the engine bay. > >4. For the ebus I just had to use those two big diodes which >access either the battery or the alternator or both (normally both) each >with a green LED signal light. Z21-A offers power from battery plus >alternator , or from battery but can not be switched to run from >alternator only. So What ? Well it just appealed to me to be able to >choose which power source in any emergency and the green lights are a feel >good feature. > > >I am offering this amendment fully expecting a flame out and ready to eat >humble pie and learn some more, mean time I will stay off the beer. > >Circuit details follow : > >Peter > > >image002.jpg > > >incoming mail is certified Virus Free. >Checked by AVG. Bob . . . ---------------------------------------- ( "Physics is like sex: sure, it may ) ( give some practical results, but ) ( that's not why we do it." ) ( ) ( Richard P. Feynman ) ----------------------------------------




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