---------------------------------------------------------- Avionics-List Digest Archive --- Total Messages Posted Tue 10/12/04: 11 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:11 AM - Re: VHF Interference by Transponder (Brian Lloyd) 2. 04:18 AM - Re: VHF Interference by Transponder (cgalley) 3. 05:34 AM - I need Help against possible FAA action (Wayne @ Aircraft Engravers) 4. 05:51 AM - Re: I need Help against possible FAA action (Al Young) 5. 06:03 AM - Re: I need Help against possible FAA action (Ralph E. Capen) 6. 06:19 AM - Re: I need Help against possible FAA action (Matthew Mucker) 7. 06:49 AM - Re: I need Help against possible FAA action (Chuck Jensen) 8. 06:59 AM - Re: I need Help against possible FAA action (N5522F) 9. 07:08 AM - Idea For Sale (Chuck Jensen) 10. 10:45 AM - Re: VHF Interference by Transponder (Fred Fillinger) 11. 04:19 PM - Re: I need Help against possible FAA action (Brian Kraut) ________________________________ Message 1 _____________________________________ Time: 04:11:52 AM PST US From: Brian Lloyd Subject: Re: Avionics-List: VHF Interference by Transponder --> Avionics-List message posted by: Brian Lloyd On Oct 11, 2004, at 11:41 PM, Dave Dykhoff wrote: > --> Avionics-List message posted by: Dave Dykhoff > > > I'm getting serious interference on my VHF (KX-155) anytime my > transponder (KX-76) issues a reply. If I go to standby on the > transponder it solves the problem. The interference has been > happening for a while, but it recently got much worse; incoming VHF > comms are unintelligible anytime the transponder is placed in reply > and is being interrogated. > > I previously had had the comm and transponder antenna coax cables > bundled together; today I physically separated them in the hope that > would fix the problem, but it had no effect. It could be RF getting in but that isn't the only possible problem. Remember, the KX-155 is going to do a good job of rejecting the transponder frequencies coming in the antenna. I would be looking somewhere else in the chain. Here is what I would check: 1. Check the shields of the coax where they attach to both radios and antennas. This is probably not the problem but one should check the easy stuff first. 2. Check the antenna grounding to the airframe. A little corrosion can make for some interesting behavior. 3. Try getting your avionics shop to hook their transponder test-set directly to the transponder while it is in the airplane, bypassing the transponder's antenna. If the noise is still present, start looking at noise getting in to the KX-155 through the power distribution. 4. Check all grounds. If one radio or the other lost its main power ground, it would use the coax and/or other grounds and shields as a return for the power. Any noise impressed upon there from the transponder's power supply would show up in almost everything. 5. If you have an oscilloscope use that to look at the power leads going into the KX-155. If you see a lot of crap from the transponder's power supply, you may be seeing the problem. And speaking of oscilloscopes, I found a great one to just keep around the shop. It is a low-cost battery-operated scope meter from Velleman. The one I got is the HPS40. It is a good digital voltmeter but it is also a 12MHz oscilloscope. As I recall, I paid about $270 for mine. It is fantastic for troubleshooting where noise in coming from in an electrical system. Brian Lloyd 6501 Red Hook Plaza brianl@lloyd.com Suite 201 +1.340.998.9447 St. Thomas, VI 00802 There is a time to laud one's country and a time to protest. A good citizen is prepared to do either as the need arises. ________________________________ Message 2 _____________________________________ Time: 04:18:04 AM PST US From: "cgalley" Subject: Re: Avionics-List: VHF Interference by Transponder --> Avionics-List message posted by: "cgalley" 1st thing are your antennas close together? 2nd. Check the grounds on your antennas. 3rd Bad antenna cable or ends. ----- Original Message ----- From: "Dave Dykhoff" Subject: Avionics-List: VHF Interference by Transponder > --> Avionics-List message posted by: Dave Dykhoff > > I'm getting serious interference on my VHF (KX-155) anytime my transponder (KX-76) issues a reply. If I go to standby on the transponder it solves the problem. The interference has been happening for a while, but it recently got much worse; incoming VHF comms are unintelligible anytime the transponder is placed in reply and is being interrogated. > > I previously had had the comm and transponder antenna coax cables bundled together; today I physically separated them in the hope that would fix the problem, but it had no effect. > > Thanks, > Dave Dykhoff > RV-8 N1063G > > ________________________________ Message 3 _____________________________________ Time: 05:34:44 AM PST US Subject: Avionics-List:I need Help against possible FAA action From: "Wayne @ Aircraft Engravers" --> Avionics-List message posted by: "Wayne @ Aircraft Engravers" Can anyone help me? The FAA has gotten an anonymous complaint that my company Aircraft Engravers is making aircraft parts illegally. Specifically our faceplate inserts for the older avionics such as the KX-170B's. We do not make the actual faceplate itself, just the inserts that fit into the old faceplate. As many of you have used the older avionics before, you know that many times the text is worn away on the older/heavily used units. So we came up with these inserts to correct the problem of illegible text. The inserts are made from plastic and are .020" to .032" thick depending on the radio which get inserted into or lay on top of the original factory faceplate. A before and after picture can be viewed at http://www.engravers.net/aircraft/fp_inserts.htm and a list of the different faceplates types we make at http://www.engravers.net/aircraft/fp_list.htm. The FAA wants to classify us as an Unapproved Parts Manufacturer of aircraft parts. We contest that the inserts that we make are not original parts and never claimed that they are. We state in our installation directions, "Have this insert installed by an avionics shop if you do not have all the proper tools, are not a qualified technician or are not sure you are capable of doing this job". ALL of our faceplate inserts are backed by our 100% satisfaction guarantee that each and every faceplate will fit properly and give your radio a nice finished look or your money back. The FAA should let us continue to make and sell these faceplate inserts to certified aircraft owners and/or avionics shops. If you have any insights or comments into this problem please let me know. Thanks. Wayne Cahoon Aircraft Engravers (860) 653-2780 (860) 653-7324 Fax http://www.engravers.net ________________________________ Message 4 _____________________________________ Time: 05:51:36 AM PST US From: "Al Young" Subject: Re: Avionics-List:I need Help against possible FAA action --> Avionics-List message posted by: "Al Young" It seems to me that the FAA is not the real problem. The real problem is you feeble attempt to use the list to advertise your product. Nice try. Al young ________________________________ Message 5 _____________________________________ Time: 06:03:16 AM PST US From: "Ralph E. Capen" Subject: Re: Avionics-List:I need Help against possible FAA action --> Avionics-List message posted by: "Ralph E. Capen" Mr Bainbridge (sp?) of B&C specialties (IIRC) had an issue similar to this a couple of years ago. Now there's a regular full page on his problem and resolution in the EAA magazine(s). IIRC, EAA brought his issue in public forum to the FAA director @ Oshkosh one year and she fixed it. It wasn't the manufacture but the use which was the real issue......sounds familiar. Good luck! -----Original Message----- From: "Wayne @ Aircraft Engravers" Subject: Avionics-List:I need Help against possible FAA action --> Avionics-List message posted by: "Wayne @ Aircraft Engravers" Can anyone help me? The FAA has gotten an anonymous complaint that my company Aircraft Engravers is making aircraft parts illegally. Specifically our faceplate inserts for the older avionics such as the KX-170B's. We do not make the actual faceplate itself, just the inserts that fit into the old faceplate. As many of you have used the older avionics before, you know that many times the text is worn away on the older/heavily used units. So we came up with these inserts to correct the problem of illegible text. The inserts are made from plastic and are .020" to .032" thick depending on the radio which get inserted into or lay on top of the original factory faceplate. A before and after picture can be viewed at http://www.engravers.net/aircraft/fp_inserts.htm and a list of the different faceplates types we make at http://www.engravers.net/aircraft/fp_list.htm. The FAA wants to classify us as an Unapproved Parts Manufacturer of aircraft parts. We contest that the inserts that we make are not original parts and never claimed that they are. We state in our installation directions, "Have this insert installed by an avionics shop if you do not have all the proper tools, are not a qualified technician or are not sure you are capable of doing this job". ALL of our faceplate inserts are backed by our 100% satisfaction guarantee that each and every faceplate will fit properly and give your radio a nice finished look or your money back. The FAA should let us continue to make and sell these faceplate inserts to certified aircraft owners and/or avionics shops. If you have any insights or comments into this problem please let me know. Thanks. Wayne Cahoon Aircraft Engravers (860) 653-2780 (860) 653-7324 Fax http://www.engravers.net ________________________________ Message 6 _____________________________________ Time: 06:19:34 AM PST US From: "Matthew Mucker" Subject: RE: Avionics-List:I need Help against possible FAA action --> Avionics-List message posted by: "Matthew Mucker" Wayne, You need a lawyer. Free legal advice from folks you meet on the internet is worth less than what you pay for it. ________________________________ Message 7 _____________________________________ Time: 06:49:12 AM PST US From: Chuck Jensen Subject: RE: Avionics-List:I need Help against possible FAA action --> Avionics-List message posted by: Chuck Jensen I'm blind and I could see through that one! Chuck -----Original Message----- From: owner-avionics-list-server@matronics.com [mailto:owner-avionics-list-server@matronics.com]On Behalf Of Al Young Subject: Re: Avionics-List:I need Help against possible FAA action --> Avionics-List message posted by: "Al Young" It seems to me that the FAA is not the real problem. The real problem is you feeble attempt to use the list to advertise your product. Nice try. Al young ________________________________ Message 8 _____________________________________ Time: 06:59:16 AM PST US From: "N5522F" Subject: RE: Avionics-List:I need Help against possible FAA action --> Avionics-List message posted by: "N5522F" You might make it clear to your prospective customers that your parts don't meet any FAA standards (TSO, PMA, whatever). You might also say they're for use in experimental aircraft only, and that the buyer and the installing mechanic must deterimine how to legally use them in a certificated aircraft. It seems to me that no one can stop you from making and selling the parts you're making, nor can the FAA take action against you, as long as you don't misrepresent the parts to the market. (I gotta say it: Something doesn't seem right here. If I were more cynical, I'd say your post is actually a disguised effort to advertise and promote your products, that FAA action against you isn't imminent as you contend.) --Mike Truffer -----Original Message----- From: owner-avionics-list-server@matronics.com [mailto:owner-avionics-list-server@matronics.com]On Behalf Of Ralph E. Capen Subject: Re: Avionics-List:I need Help against possible FAA action --> Avionics-List message posted by: "Ralph E. Capen" Mr Bainbridge (sp?) of B&C specialties (IIRC) had an issue similar to this a couple of years ago. Now there's a regular full page on his problem and resolution in the EAA magazine(s). IIRC, EAA brought his issue in public forum to the FAA director @ Oshkosh one year and she fixed it. It wasn't the manufacture but the use which was the real issue......sounds familiar. Good luck! -----Original Message----- From: "Wayne @ Aircraft Engravers" Subject: Avionics-List:I need Help against possible FAA action --> Avionics-List message posted by: "Wayne @ Aircraft Engravers" Can anyone help me? The FAA has gotten an anonymous complaint that my company Aircraft Engravers is making aircraft parts illegally. Specifically our faceplate inserts for the older avionics such as the KX-170B's. We do not make the actual faceplate itself, just the inserts that fit into the old faceplate. As many of you have used the older avionics before, you know that many times the text is worn away on the older/heavily used units. So we came up with these inserts to correct the problem of illegible text. The inserts are made from plastic and are .020" to .032" thick depending on the radio which get inserted into or lay on top of the original factory faceplate. A before and after picture can be viewed at http://www.engravers.net/aircraft/fp_inserts.htm and a list of the different faceplates types we make at http://www.engravers.net/aircraft/fp_list.htm. The FAA wants to classify us as an Unapproved Parts Manufacturer of aircraft parts. We contest that the inserts that we make are not original parts and never claimed that they are. We state in our installation directions, "Have this insert installed by an avionics shop if you do not have all the proper tools, are not a qualified technician or are not sure you are capable of doing this job". ALL of our faceplate inserts are backed by our 100% satisfaction guarantee that each and every faceplate will fit properly and give your radio a nice finished look or your money back. The FAA should let us continue to make and sell these faceplate inserts to certified aircraft owners and/or avionics shops. If you have any insights or comments into this problem please let me know. Thanks. Wayne Cahoon Aircraft Engravers (860) 653-2780 (860) 653-7324 Fax http://www.engravers.net ________________________________ Message 9 _____________________________________ Time: 07:08:12 AM PST US From: Chuck Jensen Subject: Avionics-List: Idea For Sale --> Avionics-List message posted by: Chuck Jensen Well, not really for sale, but I have an idea I'll give away. Builders and tinkers (I know--that's repetitive) are always buying things, which means they also have things to sell. Builders, trying to unload good 'stuff', is denigrated to sheepish posts to the List, mentioning they have a few odd items for anyone interested. Of course, there are a few brazen ones that make no attempt to respect the prohibition against commercialism on the list; a few make half hearted attempts to camouflage their efforts, but fool no one. Nonetheless, I've seen few people that resent being exposed to a good buy or a good product. Why should the willing sellers need to feel ashamed to expose willing buyers to a good buy? The solution? How about a separate 'For Sale' List where builder can list/unload their surplus items, rather than have to make some lame reference to Ebay. A separate list for 'Vendors' may even have merit. There's a few products out there I'd like to know about that may not have the exposure of a Garmin and King, et al. The feedback the vendors would face on the list would keep them pretty honest and help all of us sort out the good from the bad. Probably been tried, and abandoned already, but its worth a thought. No? Chuck -----Original Message----- From: owner-avionics-list-server@matronics.com [mailto:owner-avionics-list-server@matronics.com]On Behalf Of Wayne @ Aircraft Engravers Subject: Avionics-List:I need Help against possible FAA action --> Avionics-List message posted by: "Wayne @ Aircraft Engravers" Can anyone help me? The FAA has gotten an anonymous complaint that my company Aircraft Engravers is making aircraft parts illegally. Specifically our faceplate inserts for the older avionics such as the KX-170B's. We do not make the actual faceplate itself, just the inserts that fit into the old faceplate. As many of you have used the older avionics before, you know that many times the text is worn away on the older/heavily used units. So we came up with these inserts to correct the problem of illegible text. The inserts are made from plastic and are .020" to .032" thick depending on the radio which get inserted into or lay on top of the original factory faceplate. A before and after picture can be viewed at http://www.engravers.net/aircraft/fp_inserts.htm and a list of the different faceplates types we make at http://www.engravers.net/aircraft/fp_list.htm. The FAA wants to classify us as an Unapproved Parts Manufacturer of aircraft parts. We contest that the inserts that we make are not original parts and never claimed that they are. We state in our installation directions, "Have this insert installed by an avionics shop if you do not have all the proper tools, are not a qualified technician or are not sure you are capable of doing this job". ALL of our faceplate inserts are backed by our 100% satisfaction guarantee that each and every faceplate will fit properly and give your radio a nice finished look or your money back. The FAA should let us continue to make and sell these faceplate inserts to certified aircraft owners and/or avionics shops. If you have any insights or comments into this problem please let me know. Thanks. Wayne Cahoon Aircraft Engravers (860) 653-2780 (860) 653-7324 Fax http://www.engravers.net ________________________________ Message 10 ____________________________________ Time: 10:45:29 AM PST US From: "Fred Fillinger" Subject: Re: Avionics-List: VHF Interference by Transponder --> Avionics-List message posted by: "Fred Fillinger" Dave Dykhoff wrote: > > I'm getting serious interference on my VHF (KX-155) anytime my > transponder (KX-76) issues a reply. If I go to standby on the transponder > it solves the problem. > ... It isn't likely RF interference, since the replies are only about 21 microseconds long, which wouldn't be audible at the reply rate typical in flight. I had a similar problem with an AT-150, and the source was noise coming in through the 14V supply to the audio panel. A filter choke and capacitor on the 14V to the audio panel (a rather basic RST kit) fixed it, along with some alternator whine, which actually was the principal problem when using headphones. What I think was happening is that every time it replied, a large, noise-creating load is placed on the switching 1,500V pwr supply inside the xponder, so that what was heard was an audio-frequency whine for a brief time - about .3 second - needed to replenish its big, high-voltage capacitor which supplies 250+W of xmit power. Since yours is bad enough to make comm receive unintelligible, poor grounding of the xponder or even the comm is a possible suspect. What does the noise sound like? Reg, Fred F. ________________________________ Message 11 ____________________________________ Time: 04:19:23 PM PST US From: "Brian Kraut" Subject: RE: Avionics-List:I need Help against possible FAA action --> Avionics-List message posted by: "Brian Kraut" Lighten up. I think that Wayne is asking a question on a legitimate problem to a group of people where someone may have a solution just like every other question on this list. I can see how the FAA would do something like this since the engraved panels could be considered non-approved parts of the radio. My solution would be to look at the regs on placards since that is what they really are. I don't think you need an approved part if you put an engraved pre-takeoff placard on your panel, for instance. As far as Wayne and Aircraft Engravers advertizing, if you look back through the RV and avionics list archives you will see that Wayne occasionally offers an engraved solution to someone's problem, but more often just gives helpfull advice or comments. I do not know Wayne very well, but have had him engrave several panels and placard for ship's bridge consoles at my day job and can comment that he does top notch work, quickly, and at reasonable prices. My boss came to me in a rant the first time I used them because he has a friend with a local engraving business, but as soon as I showed him the panels he shut up and told me to keep using them. Flame me if you will. I am wearing my asbestos underwear. Brian Kraut Engineering Alternatives, Inc. www.engalt.com -----Original Message----- From: owner-avionics-list-server@matronics.com [mailto:owner-avionics-list-server@matronics.com]On Behalf Of Al Young Subject: Re: Avionics-List:I need Help against possible FAA action --> Avionics-List message posted by: "Al Young" It seems to me that the FAA is not the real problem. The real problem is you feeble attempt to use the list to advertise your product. Nice try. Al young