---------------------------------------------------------- Europa-List Digest Archive --- Total Messages Posted Sun 03/06/05: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 02:03 AM - Re: issues with Rotax 914 voltage regulator/rectifier? (Jan de Jong) 2. 05:15 PM - Re: Fin Comm Ant. (EuropaXSA276@aol.com) 3. 06:00 PM - Re: Fin Comm Ant. (JEFF ROBERTS) 4. 06:10 PM - FW: Baltics States Tour to include Scandinavian Rallys Auschwitz and Colditz Castle visits....... (R.C.Harrison) 5. 06:32 PM - Fin com antenna (Vaughn Teegarden) 6. 07:33 PM - Re: Fin Comm Ant. (Fred Fillinger) 7. 10:49 PM - Re: Fin Comm Ant. (Jos Okhuijsen) ________________________________ Message 1 _____________________________________ Time: 02:03:40 AM PST US From: Jan de Jong Subject: Re: Europa-List: issues with Rotax 914 voltage regulator/rectifier? --> Europa-List message posted by: Jan de Jong Duncan, ><of on the firewall. >> > >Do we need to? Mine is mounted on the firewall close to the air (exit) vent. >A temperature label stuck to hte body of the regulator has read a maximum >temp. of 70C in 200 hours of service; and this was probably during heat soak >after shutdown or during a long taxiing hold, when the regulator would have >little to do. > > Yes, there may be easier ways to get some moving air, but I think some moving air is needed. >It's agreed that mounting the regulator close to the exhaust headers >(numerous examples of this are around) gives little chance of survival.. > One can easily be lucky for quite a while (not accusing you of this - you measure) without being safe. The worst dissipation of 80W probably only happens, in most cases, when the battery is repleted fast after cranking. The heat capacity of the heatsink smoothes out the effect of such short term excesses. To attempt an estimate of this for the still air case: - specific heat for aluminium is 0.9 J/gK, - heatsink mass is 100g (just a guess), - then heat capacity is 90J/K. - this in parallel with a thermal resistance of 2K/W gives a relaxation time of 1131 seconds (2 x 90 x 2 x pi). So it takes about 19 minutes for the junction temperature to attain 2/3 of its final temperature rise, from the onset of a certain constant dissipation (I am neglecting the 0.3K/W series resistance). A 1/3 rise takes about 8 minutes, a 40% rise 10 minutes. For 80W - with a final temperature increase of 184 degrees C - 10 minutes gets you up to 75 degrees C above ambient. If then dissipation drops to 32W or below the junction temperature will rise no further and everything will still be fine - even in still air. If, on the other hand,... Jan de Jong ________________________________ Message 2 _____________________________________ Time: 05:15:35 PM PST US From: EuropaXSA276@aol.com Subject: Re: Europa-List: Fin Comm Ant. --> Europa-List message posted by: EuropaXSA276@aol.com In a message dated 3/6/2005 2:12:43 AM Central Standard Time, paul.mcallister@qia.net writes: The antenna is an E shape and its pretty tricky to get in to fit in the fin area, but with some fiddling around you can get it in the right spot. I haven't had any comms problems with this antenna. Hi Paul. I'm thinking about the Bob Archer antenna for my plane. Care to elaborate on your "pretty tricky" comment? Thanks! Brian Skelly Texas Europa # A276 TriGear See My build photos at: http://www.europaowners.org/BrianS ________________________________ Message 3 _____________________________________ Time: 06:00:16 PM PST US From: JEFF ROBERTS Subject: Re: Europa-List: Fin Comm Ant. --> Europa-List message posted by: JEFF ROBERTS Brian, I to used the Archer antenna. It is easy you just ned to fit in and make the ribs fit over it. The only trick is making sure the ribs don't run horizontal where the horizontal part of the antenna is. The ribs fit over the vertical part of the antenna fine because that part is only about an inch and a half long vertically. Just start it and you'll see how to do it as with most of the things we worry about. Jeff A258 Continuing to prepare for the pain shop. On Mar 6, 2005, at 7:14 PM, EuropaXSA276@aol.com wrote: > --> Europa-List message posted by: EuropaXSA276@aol.com > > In a message dated 3/6/2005 2:12:43 AM Central Standard Time, > paul.mcallister@qia.net writes: > The antenna is an E shape > and its pretty tricky to get in to fit in the fin area, but with some > fiddling around you can get it in the right spot. I haven't had any > comms > problems with this antenna. > > Hi Paul. I'm thinking about the Bob Archer antenna for my plane. > Care to > elaborate on your "pretty tricky" comment? Thanks! > > Brian Skelly > Texas > Europa # A276 TriGear > See My build photos at: > http://www.europaowners.org/BrianS > > ________________________________ Message 4 _____________________________________ Time: 06:10:37 PM PST US From: "R.C.Harrison" , Subject: Europa-List: FW: Baltics States Tour to include Scandinavian Rallys Auschwitz and Colditz Castle visits....... --> Europa-List message posted by: "R.C.Harrison" Hi! All interested parties. After careful consideration Ivor Phillips and I have decided to publish our intended Baltic Sates tour and invite other interested parties to join the tour. Basically the tour is to encompass the Barkaby (Stockholm) Rally, the Danish Rally (Stauning) with the German Rally (Stade) on the way back with the week between used for a circular number of stops and "stop-overs" North to South down the Eastern Baltic States. To put a little more flesh on the bones .June 2nd... Fly out via Lellystad with a stop-over at Kristianstad or Malmo (Cheap fuel in Sweden!) to Barkaby Rally pm. Friday 3rd June (Subject to favourable weather predictions this could be shortened to a Friday Fly Out getting to Barkaby in the day, but everything will need to go like clockwork with a very early departure and advance payments and own top up fuel and pre-submitted flight plans from say Southend which is open operationally early but no admin. for collecting paymnents on the day.) Stopping over Friday night and Saturday nights in Stockholm. Sunday 5th June could be used for a trip to Visby(Air museum Gotland Island.) Probably a "stop-over"... Visby is an interesting walled city of considerable historical Estonian influence on Sweden. OR a trip into Stockholm City with various Ferry trips out to the inner reaches of the archipelago and even the possibility of a visit to the Wasa (Man of War Ship) Museum or even the Maritime Museum. (Stockholm isn't cheap and it's not in the Euro! It has a great Irish Pub!) And/OR Sunday /Monday across the Swedish and Finnish Archepelegos for lunch in Mariehamn (Finland) and onwards to Tallinn (Estonia to sample the night scene"! If it's that good Tuesday as well !) continuing ... .. via Riga (Latvia) and Vilnus (Lithuania) I'm wanting input for "things to visit here" other than to have just "called in" for fuel and documentation. continuing to....Krakow (Poland visit to Austwitch) and...onwards to Colditz for a Castle tour on Thursday 9th June (BTW we won't get to see the "Glider Room" because of safety problems although there's a 1/3rd scale model which was donated to the castle after a 1993 documentary. However from the terrace, the route taken by the glider down to the below meadow can be seen.) and then ... back up Denmark to Stauning for their Rally Friday 10th June. They usually have a Friday night "bash". We hope to have a group departure built into their Display schedule for pm on Saturday 11th to get to the Stade Rally (Germany) over-night with them and... back to the UK on Sunday 12th (all weather permitting of course) We have no intention of making advance accommodation bookings (half decent taxi drivers should be able to fix suitable venues!) otherwise particularly at the Rally's, as ever, its my intention to camp! At all times it remains the Pilot in Command responsibility on decisions to fly concerning weather, aircraft condition and suitability. At times it may well be possible to file multiple loose formation flight plans but again the PIC of each aircraft will be responsible for his own routing and observance of communications and Insurances including his passengers. We will be pleased to receive tentative statements of intent with full contact details and obviously with some firm commitment soon to follow. As particulars of the tour and the group develop... I have had good communications with the Colditz people (http://www.schlosscolditz.com or search COLDITZ on Google) and there is a wealth of information on Auschwitz Birkenau (http://www.escape2Poland.co.uk ) These parts of the trip for me will provide an ultimate reminder, as did my trip to the Hiroshima Peace Museum, lest we should forget those who paid the ultimate sacrifice in the 60th anniversary year of the end of WWII since there are some in Europe who seem to deny who and what took place. I will circulate additional relevant information as it becomes available. We currently have 5 aircraft enrolled. Regards BOB Harrison G-PTAG Robt.C.Harrison ________________________________ Message 5 _____________________________________ Time: 06:32:25 PM PST US From: "Vaughn Teegarden" Subject: Europa-List: Fin com antenna clamav-milter version 0.80j on heru-ur --> Europa-List message posted by: "Vaughn Teegarden" I have installed the antennas from Advanced Aircraft Electronics. Their ad reads good. Has anyone else used them? Their web address is: http://www.advancedaircraft.com/ Vaughn Teegarden N914VA-Still chipping away-Venus is in there somewhere ________________________________ Message 6 _____________________________________ Time: 07:33:31 PM PST US From: "Fred Fillinger" Subject: Re: Europa-List: Fin Comm Ant. --> Europa-List message posted by: "Fred Fillinger" All antenna designs are compromises of one thing vs. another. A straight dipole isn't 50 ohms; Archer's antenna appears to of the type that solves the balun problem; 1.1:1 VSWR at mid-band is nice, but if you need performance at 118.5 like our nearby control tower, you need broadband. Anyway, here's yet another version with copper tape, with claimed broadband performance and natural 50 ohms impedance: http://www.express-aircraft.com/antenna_design.htm It comes out shorter that a straight dipole. Needs the ferrite beads, though. Be cautious about user reports w/o the details of what metal is or is not nearby. I have an MFJ antenna analyzer, and it's been educational to suspend different designs well above the ground and see what happens on the MFJ when things mimicking wiring or control system items are introduced within 2-3 feet of the tips. I tested a friend's Archer antenna setup, the one that's supposed to work in a fiberglass fairing on a metal airplane. Disaster -- VSWR and impedance was OK, but complete nulls in the pattern off the sides of the aircraft. Reg, Fred F. ________________________________ Message 7 _____________________________________ Time: 10:49:40 PM PST US Subject: Re: Europa-List: Fin Comm Ant. From: "Jos Okhuijsen" --> Europa-List message posted by: "Jos Okhuijsen" As Fred says, optimized antennas will be worse on other frequencies, and or be more likely influenced by not perfect conditions in or on the airframe. The simple copper tape from the manual is exactly what a comm antenna should be. Stick it on the belly and make it a bit longer and you have the perfect vor antenna. No cables near the tips then. Sounds strange maybe, but a few bucks here are better then 100 $+, whatever nice websites and good salesfolk may tell you. Regards, Jos Okhuijsen