---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 03/02/17: 14 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:30 AM - Re: Internal Balun Antenna Lead (user9253) 2. 06:24 AM - Always check the ground, yet again (Richard Girard) 3. 08:19 AM - Re: Always check the ground, yet again (Alec Myers) 4. 08:44 AM - Re: Always check the ground, yet again (Eric Page) 5. 12:54 PM - Mounting a VOR Antenna (Art Zemon) 6. 01:21 PM - Re: Mounting a VOR Antenna (Sebastien) 7. 01:21 PM - Re: Mounting a VOR Antenna (Sebastien) 8. 01:26 PM - Re: Mounting a VOR Antenna (Charlie England) 9. 01:52 PM - Re: Mounting a VOR Antenna (Robert L. Nuckolls, III) 10. 02:13 PM - Re: Mounting a VOR Antenna (bobsv35b@aol.com) 11. 03:59 PM - Re: Mounting a VOR Antenna (Art Zemon) 12. 04:25 PM - Re: Mounting a VOR Antenna (Kelly McMullen) 13. 04:48 PM - Re: Mounting a VOR Antenna (bobsv35b@aol.com) 14. 05:05 PM - Re: Mounting a VOR Antenna (bobsv35b@aol.com) ________________________________ Message 1 _____________________________________ Time: 05:30:09 AM PST US Subject: AeroElectric-List: Re: Internal Balun Antenna Lead From: "user9253" Read this article: http://www.aeroelectric.com/articles/BALUN/Balun_Fabrication.html I would go fly the plane without a balun. If you are not satisfied with the reception, then make and install balun. But why try to make it perfect when it is already good enough? -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=466798#466798 ________________________________ Message 2 _____________________________________ Time: 06:24:43 AM PST US From: Richard Girard Subject: AeroElectric-List: Always check the ground, yet again We use flashlights on a daily basis and our battery bill is pretty high because of it. We're making the leap to rechargeables but our first foray brought the old lesson about check the grounds first into play as I say, yet again. I would say the flashlight maker's name but I think the problem will be endemic to all that use the 18650 lithium ion battery. Anyway, the flashlight came in the mail, I put the battery in the charger and waited for the LED to turn green. Put battery in flashlight, hit the switch, nothing. Fiddled with it awhile, unscrewed cap/switch and put battery back in charger for another cycle. Again, no light. I unscrewed the end again only this time I noticed a white powder coming off the threads. Examination of the threads with a magnifying glass revealed that the threads were corroded and a vigorous brushing with a stainless steel brush fixed the symptom but not the problem. I compared the new flashlight with a AAA battery powered LED flashlight. The threads on the 18650 powered flashlight are bare aluminum. They have to be to complete the ground path for the circuit. The AAA flashlight has a plastic case that connects up the four batteries and has the ground path built into it. Two spring loaded pins on the forward end of the case connect to power and ground rings on a circuit board at the LED end of the flashlight. The threads are not part of the ground path. I briefly considered alodining the threads when good sense hit me with the realization that I do not need another project. A few key strokes and I was printing out a return label. So it seems to me that pretty much all the rechargeable aluminum flashlights that have no other ground path than *unprotected* threads are going to have this problem sooner or later. I was lucky in that the failure was immediate. If the manufacturer had put a 1/2 penny desiccant pack in the case I would probably have thrown it away in a year or two and been stuck with the bill. Rick Girard -- =9CBlessed are the cracked, for they shall let in the light.=9D Groucho Marx ________________________________ Message 3 _____________________________________ Time: 08:19:37 AM PST US From: Alec Myers Subject: Re: AeroElectric-List: Always check the ground, yet again I have several flashlights as you describe, both $5 affairs from Banggood an d some very expensive ones - going back 5 years. No corrosion on any threads .. I think you got unlucky! > On Mar 2, 2017, at 9:22 AM, Richard Girard wrote: > > We use flashlights on a daily basis and our battery bill is pretty high be cause of it. We're making the leap to rechargeables but our first foray brou ght the old lesson about check the grounds first into play as I say, yet aga in. > I would say the flashlight maker's name but I think the problem will be en demic to all that use the 18650 lithium ion battery. > Anyway, the flashlight came in the mail, I put the battery in the charger a nd waited for the LED to turn green. Put battery in flashlight, hit the swit ch, nothing. Fiddled with it awhile, unscrewed cap/switch and put battery ba ck in charger for another cycle. Again, no light. I unscrewed the end again o nly this time I noticed a white powder coming off the threads. Examination o f the threads with a magnifying glass revealed that the threads were corrode d and a vigorous brushing with a stainless steel brush fixed the symptom but not the problem. > I compared the new flashlight with a AAA battery powered LED flashlight. T he threads on the 18650 powered flashlight are bare aluminum. They have to b e to complete the ground path for the circuit. The AAA flashlight has a plas tic case that connects up the four batteries and has the ground path built i nto it. Two spring loaded pins on the forward end of the case connect to pow er and ground rings on a circuit board at the LED end of the flashlight. The threads are not part of the ground path. > I briefly considered alodining the threads when good sense hit me with the realization that I do not need another project. A few key strokes and I was printing out a return label. > So it seems to me that pretty much all the rechargeable aluminum flashligh ts that have no other ground path than unprotected threads are going to have this problem sooner or later. I was lucky in that the failure was immediate . If the manufacturer had put a 1/2 penny desiccant pack in the case I would probably have thrown it away in a year or two and been stuck with the bill. > > Rick Girard > > > -- > =9CBlessed are the cracked, for they shall let in the light.=9D Groucho Marx > > ________________________________ Message 4 _____________________________________ Time: 08:44:58 AM PST US Subject: Re: AeroElectric-List: Always check the ground, yet again From: Eric Page What a strange experience. I have an aluminum 18650-powered flashlight in m y flight bag that I sourced from one of the offshore discount electronics em poria. It has a clear anodized finish and no apparent ground path from tail cap to business end except through the threads. It has been illuminating m y nighttime preflight walk-arounds for several years now without fail. Very bright, very reliable, very cheap. http://preview.tinyurl.com/her9d7w Eric ________________________________ Message 5 _____________________________________ Time: 12:54:07 PM PST US From: Art Zemon Subject: AeroElectric-List: Mounting a VOR Antenna Folks, UPS brought my VOR antenna yesterday, a RAMI AV-532 . I have a couple of questions about mounting it. The installation instructions are "terse," to say the least. Am I right in assuming that neither one of the two studs should come in contact with the metal fuselage? How do I seal the antenna to the fuselage so that it is weather proof? Squirt some RTV under it before bolting it on and then run a bead of RTV around the outside edge? Just a bead around the outside? Something entirely different? Thanks, -- Art Z. -- https://CheerfulCurmudgeon.com/ *"If I am not for myself, who is for me? And if I am only for myself, what am I? And if not now, when?" Hillel* ________________________________ Message 6 _____________________________________ Time: 01:21:23 PM PST US From: Sebastien Subject: Re: AeroElectric-List: Mounting a VOR Antenna For sealing I used Alex Plus http://www.dap.com/dap-products-ph/alex-plus-acrylic-latex-caulk-plus-silicone/ On Thu, Mar 2, 2017 at 12:49 PM, Art Zemon wrote: > Folks, > > UPS brought my VOR antenna yesterday, a RAMI AV-532 > . I have a couple of questions about > mounting it. The installation instructions are "terse," to say the least. > > Am I right in assuming that neither one of the two studs should come in > contact with the metal fuselage? > > How do I seal the antenna to the fuselage so that it is weather proof? > Squirt some RTV under it before bolting it on and then run a bead of RTV > around the outside edge? Just a bead around the outside? Something entirely > different? > > Thanks, > -- Art Z. > > -- > https://CheerfulCurmudgeon.com/ > > *"If I am not for myself, who is for me? And if I am only for myself, what > am I? And if not now, when?" Hillel* > ________________________________ Message 7 _____________________________________ Time: 01:21:36 PM PST US From: Sebastien Subject: Re: AeroElectric-List: Mounting a VOR Antenna Whoops, didn't read the whole question :(. Bead around the outside edge after installation. On Thu, Mar 2, 2017 at 1:18 PM, Sebastien wrote: > For sealing I used Alex Plus > > http://www.dap.com/dap-products-ph/alex-plus-acrylic- > latex-caulk-plus-silicone/ > > On Thu, Mar 2, 2017 at 12:49 PM, Art Zemon wrote: > >> Folks, >> >> UPS brought my VOR antenna yesterday, a RAMI AV-532 >> . I have a couple of questions >> about mounting it. The installation instructions are "terse," to say the >> least. >> >> Am I right in assuming that neither one of the two studs should come in >> contact with the metal fuselage? >> >> How do I seal the antenna to the fuselage so that it is weather proof? >> Squirt some RTV under it before bolting it on and then run a bead of RTV >> around the outside edge? Just a bead around the outside? Something entirely >> different? >> >> Thanks, >> -- Art Z. >> >> -- >> https://CheerfulCurmudgeon.com/ >> >> *"If I am not for myself, who is for me? And if I am only for myself, >> what am I? And if not now, when?" Hillel* >> > > ________________________________ Message 8 _____________________________________ Time: 01:26:44 PM PST US From: Charlie England Subject: Re: AeroElectric-List: Mounting a VOR Antenna On Thu, Mar 2, 2017 at 2:49 PM, Art Zemon wrote: > Folks, > > UPS brought my VOR antenna yesterday, a RAMI AV-532 > . I have a couple of questions about > mounting it. The installation instructions are "terse," to say the least. > > Am I right in assuming that neither one of the two studs should come in > contact with the metal fuselage? > > How do I seal the antenna to the fuselage so that it is weather proof? > Squirt some RTV under it before bolting it on and then run a bead of RTV > around the outside edge? Just a bead around the outside? Something entirely > different? > > Thanks, > -- Art Z. > > According to the 2nd image on that site, there are 2 mounting holes; those shouldn't have any issue with their screws contacting the a/c structure. You can use RTV to seal it to the fuselage, but be sure you get 'sensor safe' RTV for that use. Typical RTV releases acetic acid, which is corrosive. https://en.wikipedia.org/wiki/RTV_silicone I couldn't find the installation docs on the site, but it's logical that the pair of inner terminals would connect to the balun, and neither of those should contact the a/c structure. Note that since it's already a 50 ohm antenna, all the balun does is convert the transmission line from balanced, which is what the 'cat whisker' VOR antenna is, to 'unbalanced', which would be your coax that runs to the receiver. I think Joe pointed out that you can just hook the coax center lead to one terminal & the shield to the other, & go fly. It'll probably work perfectly, until some day you take it to a real antenna range and hook a multi-kilobuck RF analyzer to it. Then it won't work right, because that multi-kilobuck tester said it doesn't. Charlie ________________________________ Message 9 _____________________________________ Time: 01:52:23 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Mounting a VOR Antenna > I think Joe pointed out that you can just hook the coax center > lead to one terminal & the shield to the other, & go fly. It'll > probably work perfectly . . . Cessna flirted with baluns on their vertical fin cat-whiskers but the experiment didn't last long. I think for the duration of my tenure there (~5 years) they simply connected the coax shield and center to the two whiskers. >. . . until some day you take it to a real antenna range and hook a >multi-kilobuck RF analyzer to it. Then it won't work right, because >that multi-kilobuck tester said it doesn't . . . The balun shown at http://tinyurl.com/yytxwd3 is easy to make and would keep the $kilo$ tester happy. Bob . . . ________________________________ Message 10 ____________________________________ Time: 02:13:27 PM PST US From: bobsv35b@aol.com Subject: Re: AeroElectric-List: Mounting a VOR Antenna Good Afternoon Art, I have not been following this discussion, but it appears to me that you have an antenna that was designed to be mounted in a vertical fn or on the belly of an airplane very near the aft point of the fuselage. Some years ago, those wre used at the rear of Bonanzas just barely ahead of the aft bulkhead. In any case, if it is not mounted quite far away from a flat portion of the fuselage, it wll have lousy reception. On the other side of that question, at the range (distance) from the station we tend to be using such an antennna, a wet noodle would probably work OK. Enroute most of us use a GPS to figure out where we are. If we are shooting a VOR approach or an approach using a localizer, we are so close to the transmitting antenna , it would be hard NOT to get an adequate signal. What am I missing? Happy Skies, Old Bob -----Original Message----- From: Art Zemon Sent: Thu, Mar 2, 2017 2:54 pm Subject: AeroElectric-List: Mounting a VOR Antenna Folks, UPS brought my VOR antenna yesterday, a RAMI AV-532. I have a couple of questions about mounting it. The installation instructions are "terse," to say the least. Am I right in assuming that neither one of the two studs should come in contact with the metal fuselage? How do I seal the antenna to the fuselage so that it is weather proof? Squirt some RTV under it before bolting it on and then run a bead of RTV around the outside edge? Just a bead around the outside? Something entirely different? Thanks, -- Art Z. ________________________________ Message 11 ____________________________________ Time: 03:59:30 PM PST US From: Art Zemon Subject: Re: AeroElectric-List: Mounting a VOR Antenna Thanks, everybody. I'm glad that I didn't spend a lot of money on a cable with an internal balun. I will apply a bead of "sensor safe" RTV to the VOR antenna after mounting it and expect to fly high 'n' dry. Cheers, -- Art Z. -- https://CheerfulCurmudgeon.com/ *"If I am not for myself, who is for me? And if I am only for myself, what am I? And if not now, when?" Hillel* ________________________________ Message 12 ____________________________________ Time: 04:25:41 PM PST US Subject: Re: AeroElectric-List: Mounting a VOR Antenna From: Kelly McMullen Old Bob, You are probably correct for "most" VOR/Loc approaches, but some, rather than being within 10-12 mi of the transmitter, go more than 20 nm from the VOR and would probably do a lot of hunting with the needle at that range. While we do use GPS a lot, a lot of aircraft do not have a certified GPS in the panel, so the VOR is the "legal" nav method, and some airways still have 100 or slightly more nm from VOR at the changeover point. A good antenna with good install will receive that 100nm no sweat at say 10,000 ft. On 3/2/2017 3:09 PM, bobsv35b@aol.com wrote: > Good Afternoon Art, > > I have not been following this discussion, but it appears to me that > you have an antenna that was designed to be mounted in a vertical fn or > on the belly of an airplane very near the aft point of the fuselage. > Some years ago, those wre used at the rear of Bonanzas just barely ahead > of the aft bulkhead. > > In any case, if it is not mounted quite far away from a flat portion of > the fuselage, it wll have lousy reception. > > On the other side of that question, at the range (distance) from the > station we tend to be using such an antennna, a wet noodle would > probably work OK. Enroute most of us use a GPS to figure out where we > are. If we are shooting a VOR approach or an approach using a localizer, > we are so close to the transmitting antenna , it would be hard NOT to > get an adequate signal. > > What am I missing? > > Happy Skies, > > Old Bob > > > -----Original Message----- > From: Art Zemon > To: aeroelectric-list > Sent: Thu, Mar 2, 2017 2:54 pm > Subject: AeroElectric-List: Mounting a VOR Antenna > > Folks, > > UPS brought my VOR antenna yesterday, a RAMI AV-532 > . I have a couple of questions > about mounting it. The installation instructions are "terse," to say the > least. > > Am I right in assuming that neither one of the two studs should come in > contact with the metal fuselage? > > How do I seal the antenna to the fuselage so that it is weather proof? > Squirt some RTV under it before bolting it on and then run a bead of RTV > around the outside edge? Just a bead around the outside? Something > entirely different? > > Thanks, > -- Art Z. ________________________________ Message 13 ____________________________________ Time: 04:48:25 PM PST US From: bobsv35b@aol.com Subject: Re: AeroElectric-List: Mounting a VOR Antenna Good Evening Kelly, My point, not well made, is that the type of antenna he is using will not have a good reception pattern mounted close to the ground plane of the airframe. However. it will work adequately close to the VOR or Localizer transmitter. I still like the blades on the tail, but they are expensive. The antenna in question will work quite well mounted on the fixed vertical tail feather of a Tri Pacer!! Happy Skies, Old Bob -----Original Message----- From: Kelly McMullen Sent: Thu, Mar 2, 2017 6:27 pm Subject: Re: AeroElectric-List: Mounting a VOR Antenna Old Bob, You are probably correct for "most" VOR/Loc approaches, but some, rather than being within 10-12 mi of the transmitter, go more than 20 nm from the VOR and would probably do a lot of hunting with the needle at that range. While we do use GPS a lot, a lot of aircraft do not have a certified GPS in the panel, so the VOR is the "legal" nav method, and some airways still have 100 or slightly more nm from VOR at the changeover point. A good antenna with good install will receive that 100nm no sweat at say 10,000 ft. On 3/2/2017 3:09 PM, bobsv35b@aol.com wrote: > Good Afternoon Art, > > I have not been following this discussion, but it appears to me that > you have an antenna that was designed to be mounted in a vertical fn or > on the belly of an airplane very near the aft point of the fuselage. > Some years ago, those wre used at the rear of Bonanzas just barely ahead > of the aft bulkhead. > > In any case, if it is not mounted quite far away from a flat portion of > the fuselage, it wll have lousy reception. > > On the other side of that question, at the range (distance) from the > station we tend to be using such an antennna, a wet noodle would > probably work OK. Enroute most of us use a GPS to figure out where we > are. If we are shooting a VOR approach or an approach using a localizer, > we are so close to the transmitting antenna , it would be hard NOT to > get an adequate signal. > > What am I missing? > > Happy Skies, > > Old Bob > > > -----Original Message----- > From: Art Zemon > To: aeroelectric-list > Sent: Thu, Mar 2, 2017 2:54 pm > Subject: AeroElectric-List: Mounting a VOR Antenna > > Folks, > > UPS brought my VOR antenna yesterday, a RAMI AV-532 > . I have a couple of questions > about mounting it. The installation instructions are "terse," to say the > least. > > Am I right in assuming that neither one of the two studs should come in > contact with the metal fuselage? > > How do I seal the antenna to the fuselage so that it is weather proof? > Squirt some RTV under it before bolting it on and then run a bead of RTV > around the outside edge? Just a bead around the outside? Something > entirely different? > > Thanks, > -- Art Z. ________________________________ Message 14 ____________________________________ Time: 05:05:04 PM PST US From: bobsv35b@aol.com Subject: Re: AeroElectric-List: Mounting a VOR Antenna Good Evening Kelly If I may make another comment, I think you will find that most low altitude VOR airways have the VORs less tham one hundred miles apart. Back in the nineties, I had to do some testing to get some blade antennas approved. The FEDs only asked that I check the reception pattern 50 mles from the station at ten thousand feet or less. Happy Skies, Old Bob -----Original Message----- From: bobsv35b Sent: Thu, Mar 2, 2017 6:46 pm Subject: Re: AeroElectric-List: Mounting a VOR Antenna Good Evening Kelly, My point, not well made, is that the type of antenna he is using will not have a good reception pattern mounted close to the ground plane of the airframe. However. it will work adequately close to the VOR or Localizer transmitter. I still like the blades on the tail, but they are expensive. The antenna in question will work quite well mounted on the fixed vertical tail feather of a Tri Pacer!! Happy Skies, Old Bob -----Original Message----- From: Kelly McMullen Sent: Thu, Mar 2, 2017 6:27 pm Subject: Re: AeroElectric-List: Mounting a VOR Antenna Old Bob, You are probably correct for "most" VOR/Loc approaches, but some, rather than being within 10-12 mi of the transmitter, go more than 20 nm from the VOR and would probably do a lot of hunting with the needle at that range. While we do use GPS a lot, a lot of aircraft do not have a certified GPS in the panel, so the VOR is the "legal" nav method, and some airways still have 100 or slightly more nm from VOR at the changeover point. A good antenna with good install will receive that 100nm no sweat at say 10,000 ft. On 3/2/2017 3:09 PM, bobsv35b@aol.com wrote: > Good Afternoon Art, > > I have not been following this discussion, but it appears to me that > you have an antenna that was designed to be mounted in a vertical fn or > on the belly of an airplane very near the aft point of the fuselage. > Some years ago, those wre used at the rear of Bonanzas just barely ahead > of the aft bulkhead. > > In any case, if it is not mounted quite far away from a flat portion of > the fuselage, it wll have lousy reception. > > On the other side of that question, at the range (distance) from the > station we tend to be using such an antennna, a wet noodle would > probably work OK. Enroute most of us use a GPS to figure out where we > are. If we are shooting a VOR approach or an approach using a localizer, > we are so close to the transmitting antenna , it would be hard NOT to > get an adequate signal. > > What am I missing? > > Happy Skies, > > Old Bob > > > -----Original Message----- > From: Art Zemon > To: aeroelectric-list > Sent: Thu, Mar 2, 2017 2:54 pm > Subject: AeroElectric-List: Mounting a VOR Antenna > > Folks, > > UPS brought my VOR antenna yesterday, a RAMI AV-532 > . I have a couple of questions > about mounting it. The installation instructions are "terse," to say the > least. > > Am I right in assuming that neither one of the two studs should come in > contact with the metal fuselage? > > How do I seal the antenna to the fuselage so that it is weather proof? > Squirt some RTV under it before bolting it on and then run a bead of RTV > around the outside edge? Just a bead around the outside? Something > entirely different? > > Thanks, > -- Art Z. ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.