---------------------------------------------------------- Avionics-List Digest Archive --- Total Messages Posted Sat 12/25/04: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 10:22 AM - Wow (Bob Gibfried) 2. 11:12 AM - Re: Wow (Brian Lloyd) 3. 08:23 PM - Altimeters- TSO vs non TSO () 4. 09:03 PM - Re: coax (N1deltawhiskey@aol.com) ________________________________ Message 1 _____________________________________ Time: 10:22:57 AM PST US From: "Bob Gibfried" Subject: Avionics-List: Wow --> Avionics-List message posted by: "Bob Gibfried" When I wrote "Choice" never expected this kind of response. Have never seen 29 messages on this list. Thanks to all who contributed. Next question. Have a 1955 certified aircraft plus a home built with the usual Walmart engine instruments. On the certified aircraft have had the flight instruments rebuilt one by one and now starting with the engine instruments. I plan to replace the old steam engine gauges with the new digital gauges. Bought the new digital RPM gauge and an engineer who worked at the firm said one problem with the new gauges is RF interference. Said that he saw one installation that lost the oil pressure/temp gauge readings whenever you keyed the mike, even with double, shielded wires. Every installation had to be custom tested because of different radio packages. Anyone with any experience with the new gauges before I waste some $2,000. Are some better than others? Would appreciate comments. Thanks Bob, Wichita ________________________________ Message 2 _____________________________________ Time: 11:12:47 AM PST US From: Brian Lloyd Subject: Re: Avionics-List: Wow --> Avionics-List message posted by: Brian Lloyd On Dec 25, 2004, at 12:22 PM, Bob Gibfried wrote: > Bought the new digital RPM gauge and an engineer who worked at the > firm said > one problem with the new gauges is RF interference. Said that he saw > one > installation that lost the oil pressure/temp gauge readings whenever > you > keyed the mike, even with double, shielded wires. Every installation > had to > be custom tested because of different radio packages. > > Anyone with any experience with the new gauges before I waste some > $2,000. > Are some better than others? Would appreciate comments. It can be a problem but that problem is usually solvable. Proper shielding and bypassing helps as does cleaning and fixing the antenna wiring for the comm. If you have a problem: 1. bypass the leads to ground at the engine monitor using .001 uFd disc ceramic caps on both leads; 2. add ferrite beads to the sensor wiring; 3. make sure your antennas are securely bonded to the skin of the airframe. Brian Lloyd 6501 Red Hook Plaza brianl@lloyd.com Suite 201 +1.340.998.9447 St. Thomas, VI 00802 I fly because it releases my mind from the tyranny of petty things . . . Antoine de Saint-Exupry ________________________________ Message 3 _____________________________________ Time: 08:23:29 PM PST US From: Subject: Avionics-List: Altimeters- TSO vs non TSO --> Avionics-List message posted by: Avionics-List message previously posted by: "Fred Fillinger" > ....skip....... It cannot be installed in a production aircraft, unless it > is FAA-approved by other means, such as an STC.....skip.....>> >> My question to you is: What is the basis for your statement above? > Think it works like this. Part 91 isn't the only rule for maintaining > type-certificated aircraft, but also Parts 21 and 43. These make it > clear it to me at least that only actual aircraft parts go into actual > airplanes....skip... > However, an altimeter is not a trivial item, and the Regs forbid > anyone from making one and selling it as an aircraft part, except for > homebuilts and ultralights. If they sell a nonTSOd instrument but > with a PMA, maybe a shop might go with that, if it's not the specific > part the airframe mfr used. Is there such an animal out there? None > of the instruments I have, sold for homebuilt only, say PMA. Fred F. 12/25/2004 Hello Fred, Thanks for your prompt and on point response. I am inclined to agree. FAR Sec21.303 says "....no person may produce a modification or replacement part for sale for installation on a type certificated product unless it is produced pursuant to a Parts Manufacturer Approval issued under this subpart."** That would seem to prevent the manufacture of non approved parts intended to be installed in type certificated aircraft. But what FAR Sec in Part 43, or elsewhere in the regulations, do you feel prevents the installation of non approved parts in type certificated aircraft? The closest that I can come to such a prohibition is FAR Sec 43.13 (b) which says "Each person maintaining or altering, or performing preventive maintenance, shall do that work in such a manner and use materials of such a quality, that the condition of the aircraft, airframe, aircraft engine, propeller, or appliance worked on will be at least equal to its original or properly altered condition with regard to aerodynamic function, structural strength, resistance to vibration and deterioration, and other qualities affecting airworthiness).## Thanks for your help. OC **PS: This is the FAR that Bill Bainbridge of B&C was accused of violating by the FAA in a famous case in which the FAA was forced to drop the charges and apologize. ##PPS: We had some pompous FAA ass who made a presentation to our local EAA Chapter several years ago that tried to tell us that that section of the FAR's meant that we could not make modifications to our amateur built experimental aircraft that improved any of those characteristics because the aircraft must remain equal to the condition that it was in when it received its original airworthiness inspection. ________________________________ Message 4 _____________________________________ Time: 09:03:12 PM PST US From: N1deltawhiskey@aol.com Subject: Re: Avionics-List: coax --> Avionics-List message posted by: N1deltawhiskey@aol.com Bob, RG-400 cable seems to be the preferred for most applications because of lower loss characteristics, but am not an expert on this. You might consider posting this to the Aerolectric list which is somewhat more active and addresses questions like this. Doug Windhorn In a message dated 12/23/2004 9:54:29 PM Pacific Standard Time, bob@whitek.com writes: > I want to install a Garmin GNC 300XL. They mention 50 Ohm, but so far I've > missed finding the instructions on what coax to use to connect the intenna > to the black box. What parts are recommended for the antenna cable and the > connectors, which are BNC on both ends? Does anyone sell made-up cables, or > should one install the connectors oneself? >