skippydiesel Posted Monday at 04:28 AM Author Posted Monday at 04:28 AM (edited) 1 hour ago, Geoff_H said: I think that you maybe right. Is there a difference between the shield and the ground plane. My experience is with instruments. Hi Geoff - from one electronically blind pilot to another :- The Ground Plane on a metal aircraft is usually the fuselage. On a composite aircraft, one must be installed. For best transmit/receive, the composite GP will have dimensions compatible with the system wave length. Sometimes the GP dimensions are compromised by the physical limitations of the aircraft shape/dimensions. A GP can be made of almost any metal eg aluminium/copper foil./sheet. Can be arranged in a cross shape ie not a solid plate. The shield, as in co-axial cable, is to prevent stray current (from any source) effecting the quality of the reception/transmission. 😈 Edited Monday at 04:30 AM by skippydiesel 1
BrendAn Posted Monday at 04:33 AM Posted Monday at 04:33 AM 1 minute ago, skippydiesel said: Hi Geoff - from one electronically blind pilot to another :- The Ground Plane on a metal aircraft is usually the fuselage. On a composite aircraft, one must be installed. For best transmit/receive, the composite GP will have dimensions compatible with the system wave length. Sometimes the GP dimensions are compromised by the physical limitations of the aircraft shape/dimensions. A GP can be made of almost any metal eg aluminium/copper foil./sheet. Can be arranged in a cross shape ie not a solid plate. The shield, as in co-axial cable, is to prevent stray current (from any source) effecting the quality of the reception/transmission. 😈 my antenna from mendehlsons came with foil tape to make a ground plane if needed. i am thinking my fuse tube may not have a good earth to the battery so on the weekend i will try a jumper wire from antenna mount to bat neg.
BrendAn Posted Monday at 04:34 AM Posted Monday at 04:34 AM as far as voltage regulators go, its pity powermate regs are not made anymore. very robust and i get a constant 14v 1
Red Posted Monday at 05:19 AM Posted Monday at 05:19 AM (edited) Geoff is confusing shielding as you would do to a signal wire to an instrument or P Lead with the outer braid of an Antenna coax which as well as providing shielding of the inner also has to form a baseplane and is connected both ends Edited Monday at 05:19 AM by Red 1
Red Posted Monday at 05:22 AM Posted Monday at 05:22 AM (edited) 54 minutes ago, BrendAn said: my antenna from mendehlsons came with foil tape to make a ground plane if needed. i am thinking my fuse tube may not have a good earth to the battery so on the weekend i will try a jumper wire from antenna mount to bat neg. It's actually better for the antenna if it's baseplane is independent to the aircraft ground, though in many aircraft it isn't. P.s. re questioning your airframe grounding, get yourself a cheap multimeter ....no need to go trying jumping stuff blindly Edited Monday at 05:29 AM by Red 1 1
Red Posted Monday at 05:44 AM Posted Monday at 05:44 AM Note to admin, can we have a longer time to edit posts, I know it's to preserve context in replies but its ridiculously short. Admittedly its a fault of mine that I often don't explain things properly in my posts and need to edit. 1 1
BrendAn Posted Monday at 05:55 AM Posted Monday at 05:55 AM 30 minutes ago, Red said: It's actually better for the antenna if it's baseplane is independent to the aircraft ground, though in many aircraft it isn't. P.s. re questioning your airframe grounding, get yourself a cheap multimeter ....no need to go trying jumping stuff blindly it takes a minute to run a jumper wire to earth. and that will tell me straight away. why do i want a cheap multimeter , i already have 2 good ones,😁 1 1
Red Posted Monday at 06:10 AM Posted Monday at 06:10 AM (edited) 15 minutes ago, BrendAn said: it takes a minute to run a jumper wire to earth. and that will tell me straight away. why do i want a cheap multimeter , i already have 2 good ones,😁 What an odd way of thinking, running a jumper doesn't tell you whether it actually changed anything if the thing you are trying to fix doesnt show change....unless you put a meter on it before and after Edited Monday at 06:11 AM by Red
BrendAn Posted Monday at 06:17 AM Posted Monday at 06:17 AM 2 minutes ago, Red said: What an odd way of thinking, running a jumper doesn't tell you whether it actually changed anything if the thing you are trying to fix doesnt show change....unless you put a meter on it before and after So you say if I chuck a jumper on there and the radio comes good I have achieved nothing. Its a quick job on my xair. Battery and antenna are only a meter apart.
Red Posted Monday at 06:29 AM Posted Monday at 06:29 AM No read my post again. What I'm saying is if you jump it and it doesnt fix the radio you still dont know if you have a bad airframe ground. Multiple problems in electrics are common. 1
danny_galaga Posted Monday at 06:36 AM Posted Monday at 06:36 AM 51 minutes ago, Red said: Note to admin, can we have a longer time to edit posts, I know it's to preserve context in replies but its ridiculously short. Admittedly its a fault of mine that I often don't explain things properly in my posts and need to edit. Many of us have asked this. Not going to happen. You've got 15 minutes and then all your mistakes are locked in forever 😄
BrendAn Posted Monday at 06:38 AM Posted Monday at 06:38 AM 1 minute ago, danny_galaga said: Many of us have asked this. Not going to happen. You've got 15 minutes and then all your mistakes are locked in forever 😄 Become a first class member and you get 30 minutes 1 1
Red Posted Monday at 06:51 AM Posted Monday at 06:51 AM 12 minutes ago, danny_galaga said: Many of us have asked this. Not going to happen. You've got 15 minutes and then all your mistakes are locked in forever 😄 Dagnabbit!!!.......condemned to become the laughing stock of generations to come🤪 2
skippydiesel Posted Monday at 07:47 AM Author Posted Monday at 07:47 AM 3 hours ago, BrendAn said: i am thinking my fuse tube may not have a good earth to the battery so on the weekend i will try a jumper wire from antenna mount to bat neg. I am a long time advocate of running dedicated earth return/neutral wire rather than relying on the airframe/chassis. The added weight, cost & complexity is minimal and you are assured of a good low resistance return at all times. Improves the performance and service life, of all 12V systems.😈 1
BrendAn Posted Monday at 07:52 AM Posted Monday at 07:52 AM 3 minutes ago, skippydiesel said: I am a long time advocate of running dedicated earth return/neutral wire rather than relying on the airframe/chassis. The added weight, cost & complexity is minimal and you are assured of a good low resistance return at all times. Improves the performance and service life, of all 12V systems.😈 I agree. I am going to check where all my earths are running too .
Red Posted Monday at 07:53 AM Posted Monday at 07:53 AM 5 minutes ago, skippydiesel said: I am a long time advocate of running dedicated earth return/neutral wire rather than relying on the airframe/chassis. The added weight, cost & complexity is minimal and you are assured of a good low resistance return at all times. Improves the performance and service life, of all 12V systems.😈 Ground loops await
BrendAn Posted Monday at 07:55 AM Posted Monday at 07:55 AM 1 minute ago, Red said: Ground loops await Why.
BrendAn Posted Monday at 07:57 AM Posted Monday at 07:57 AM 1 hour ago, Red said: Dagnabbit!!!.......condemned to become the laughing stock of generations to come🤪 Why don't you pay a few dollars a year . It supports the running of this site and you will get your 30 minutes. 1
BurnieM Posted Monday at 09:35 AM Posted Monday at 09:35 AM Stop! There is a big difference between a battery earth and an antenna ground plane. Get some real knowledge before you do anything else. 1
BrendAn Posted Monday at 10:15 AM Posted Monday at 10:15 AM 38 minutes ago, BurnieM said: Stop! There is a big difference between a battery earth and an antenna ground plane. Get some real knowledge before you do anything else. That's a big help . Why don't you explain what you are talking about. The xair antenna is on a metal bracket on the fuse boom so it should be earthed to the battery anyway. 1
danny_galaga Posted Monday at 11:12 AM Posted Monday at 11:12 AM (edited) 3 hours ago, BrendAn said: Why don't you pay a few dollars a year . It supports the running of this site and you will get your 30 minutes. A full 30 minutes 😲 Here's a post of mine on a different forum. 2004. Notice the link in the first post? https://forum.arcadecontrols.com/index.php/topic,20073.0.html#msg161529 Edited Monday at 11:14 AM by danny_galaga 1
Red Posted Monday at 04:35 PM Posted Monday at 04:35 PM 5 hours ago, danny_galaga said: A full 30 minutes 😲 Here's a post of mine on a different forum. 2004. Notice the link in the first post? https://forum.arcadecontrols.com/index.php/topic,20073.0.html#msg161529 Some people here need to learn to pay head to the words of the Grand high prophet of the holy noodle.😁 1
Geoff_H Posted Monday at 09:30 PM Posted Monday at 09:30 PM In the 1970's when we first used computers in industry for control we would get many failures, almost always on computer board connections, we would always carry an ink rubber to remove oxides, more often happening in we weather. We were told by plug manufacturers that 30,000 psi connection pressure was needed to prevent high resistance connections. I believe that earth connections should be checked regularly, particularly after a wet period like the east coast is experiencing 1 1 3
skippydiesel Posted Monday at 10:38 PM Author Posted Monday at 10:38 PM 14 hours ago, Red said: Ground loops await In theory, possible. In practise, unlikly. The return, to -battery terminal, is connected to all major metal components (airframe in a metal aircraft, engine & subframes in composite). All electrical systems are connected to the return (various ways eg buss) & by default, airframe/subframes. Most home mechanics, working with 12V systems, are unaware of just how little corrosion can increase resistance or even completely interrupt a connection, making a system operate below optimum to not operate at all. They tend to pay more attention to +posative/power connections, not realising that for the current to flow (well)/ system to work, the -negative is just as important.😈 1 1
Geoff_H Posted Tuesday at 03:56 AM Posted Tuesday at 03:56 AM Just a reminder, do not remove oxide from electrical contract surfaces with carborundum (emery) it attaches small quantities to the surface and will oxidise with electrical current. 1 4
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