---------------------------------------------------------- Yak-List Digest Archive --- Total Messages Posted Wed 05/20/09: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:09 AM - Re: Engine or prop judder on 18 T (A. Dennis Savarese) 2. 11:13 AM - placards (Bill VonDane / Whiskey Victor) 3. 03:21 PM - Wealthy? (byronmfox) 4. 06:50 PM - yak 52 fuel instrument (Stephen Morrey) 5. 07:53 PM - Re: yak 52 fuel instrument (keithmckinley) 6. 08:12 PM - Re: Re: White Paper on Russian Generator System (Yak Pilot) 7. 08:45 PM - Re: Interference of GPS on Becker VHF (Yak Pilot) ________________________________ Message 1 _____________________________________ Time: 06:09:55 AM PST US From: "A. Dennis Savarese" Subject: Re: Yak-List: Engine or prop judder on 18 T Vic, When setting the prop blades (assuming it is a 2 blade Russian paddle prop), it is important the length of both blades as measured from the outside edge of the collar under the counter weight clamp, be equal. Then the blade angles should be set afterwards. Whenever a counter weight clamp is loosened, make absolutely certain the counter weight clamp is flush against the outer edge of the sleeve below it all the way around before tightening the clamp nut. If this is not done, there will be an imbalance. If you have the typical Yak 18T spinner installed, try removing it completely including the backing plate and test fly again. I'm just grabbing at straws here, but you might try opening and closing the cooling louvers to see if that changes anything. Louvers without the anti-rattle springs installed might cause a vibration because the louvers are "shaking" at higher speeds. Make sure that the cowl mounting bushings are not totally worn out and you can not shake the upper and/or lower cowl at the rear where the pins are located. Does the front of the upper and lower cowl fit snugly against the cowl ring anti-chafe ring? Check all the cowl mounting brackets for cracks, particularly where the flat sections of the brackets mate with the round tube. Make sure each bracket is secure on the cylinder and the ring. Check the security of all of the engine baffles and baffle pads. Check the security of each of the cooling ducts, particularly where it mounts to the cowl ring. Check the carburetor intake and heat door assembly for security as well. During flight and particularly on Yak 52's, the nose wheel spins during flight. If the nose wheel assembly is out of balance, which you typically can feel when landing because of the higher speeds, and the nose wheel tire and hub are rotating in flight at higher speeds, it could be a wheel vibration. Who knows? Anything is possible. It will be very interesting to know what you try and if you figure out what is causing the vibration. Dennis ----- Original Message ----- From: Vic To: yak-list@matronics.com Sent: Tuesday, May 19, 2009 4:25 PM Subject: Yak-List: Engine or prop judder on 18 T Hello everybody, our 18 T has developed an engine or prop judder since last year that can be noticed mainly in high speed low passes at , say, 70 % engine speed and over 250 kph . We replaced all engine mounting rubbers, did a dynamic prop balancing on the ground with up to 90 % engine speed and the engine felt real smooth. But in the air at high speed dives the shaking of the engine/prop was still there - at a very reduced rate, but still noticeable . The setting of the blades was checked and seemed to be allright in the dynamic balancing . Could we have a problem with the prop hub in case the prop goes to fully coarse in the dive and the blade angles in this condition might be different for each blade ? We suspect some sort of backlash in the hub different for each side ? Has anybody an idea on that one ? Or could it be an aerodynamic effect specific for the 18 T ? We will dig deeper next weekend but any ideas would be appreciated. Regards Helga and Vic Read this topic online here: http://forums.matronics.com/viewtopic.php?p=244696#244696 ________________________________ Message 2 _____________________________________ Time: 11:13:00 AM PST US From: "Bill VonDane / Whiskey Victor" Subject: Yak-List: placards Anyone have good photos of the original (and translated) panels and controls placards? Thanks! -Bill ---------------------------------------------- Whiskey Victor / ePanel Builder www.whiskeyvictor.com ________________________________ Message 3 _____________________________________ Time: 03:21:44 PM PST US Subject: Yak-List: Wealthy? From: byronmfox Delighted to hear it! -If so, don't bother to bring your RPA Challenge Coin to All Red Star at Porterville. You can happily buy the rounds at th e bar. -For those less wealthy, order your coin now and I'll bring it wi th me. -- ...Blitz Byron M. Fox RPA Online Store 80 Milland Drive Mill Valley, CA 94941 415-307-2405 ________________________________ Message 4 _____________________________________ Time: 06:50:23 PM PST US Subject: Yak-List: yak 52 fuel instrument From: Stephen Morrey 1.Does anyone know where I can get the schematic for the 52 fuel instrument. My left wing light panel seems to be working fine. The right wing panel jumps from 60 L to 40L and then remains at 40L and on very low fuel jumps back to 60L. 2. Does any one know where I can purchase a functioning unit or perhaps trade in/ purchase for a functioning unit. 3. Does anyone have any suggestions on what might be the problem with mine. Thanks Steve Morrey MI USA ________________________________ Message 5 _____________________________________ Time: 07:53:00 PM PST US Subject: Yak-List: Re: yak 52 fuel instrument From: "keithmckinley" There are plenty of experts on this board and I'm not one of them. One possibility is: if you have a rheostat type sending unit, over time it can wear, especially in the spot you describe (where you usually have the normal fuel levels). -------- Keith McKinley 700 HS KFIT Read this topic online here: http://forums.matronics.com/viewtopic.php?p=244858#244858 ________________________________ Message 6 _____________________________________ Time: 08:12:31 PM PST US From: Yak Pilot Subject: Re: Yak-List: Re: White Paper on Russian Generator System Dear Shahnow, please write me directly at markbitterlich@embarqmail.com- and send me your attachment again.- I did not get it on the YAK list.- =0A=0AI am reading what you said carefully, and I think I might know what y ou are doing.- =0A=0AWhen you reduce your power supply voltage to ZERO, y ou are checking between the GEN and MAINS terminals with an OHM meter.- T hat is my guess anyway?- Or are you still seeing battery voltage on the G EN side?- =0A=0ATry this first:- =0A=0ADisconnect the B terminal from A NYTHING.- In fact, just take a DMR 200 device with nothing hooked to it a nd you should be able to see a complete OPEN between-GEN and MAINS.- No connection should be there at all.-- =0A=0ANow apply 28 volts to-the terminal marked "A"-with ground connected to the-"-" contact on the DM R-200.- -The letter "A" has a flat top to it.--/-\-- like that with a flat line on the top that I can't put in with this keyboard.- It i s right above the GEN terminal on the right side.- You should hear a pret ty loud sound as the MAIN CONTACTOR relay closes.- This will connect MAIN S to GEN and it will be a LOUD SOUND when you do this as the relay closes. --- Remove the power to "A" and you will hear the relay open and powe r will be disconnected between GEN and MAINS.- This tests just the main c ontactor alone.- =0A=0AWith the test you are running, the problem you are having is NOT with the DMR-200 but with your actual test equipment.- It is very very tricky to test this device and make it work the way it actuall y works in the aircraft.- I suspect everything you have is working proper ly the way you explained it.. but it is not actually doing what you might t hink it is doing.- I know that sounds strange, but this is a very complic ated device.- What is happening is that your power supply is not exactly duplicating what happens in the an actual aircraft with a real generator in there instead of a power supply.- I suspect your particular power supply is now allowing reverse current.- =0A=0ALet me explain.- =0A=0AWith th e way you have it set up, the relay will stay closed as you have said, beca use of the battery now powering the device and keeping it closed.-- Her e is how you can complete your test.- Do exactly as you have already done .- When you get to the point where you reduce the power supply voltage to zero... do exactly the same thing and then REMOVE the PLUS wire from the p ower supply to the GEN contact.- =0A=0ANow take a load... something like a big 28 volt light bulb.- A landing light will do.- Connect it between your battery MINUS lead and the GEN contact.- As soon as you do this, cu rrent will flow from the MAIN contact to the GEN contact and will light up the bulb, but only very briefly.- - This is REVERSE CURRENT!- As soon as the DMP-200 senses this reverse current with the reverse current relay, the device will OPEN and the contact between GEN and MAIN will open.- =0A=0ARemember the way it works in the aircraft.- =0A=0ABy putting in a j umper between the B and GEN and then putting power on the GEN/B connection, you are simulating an aircraft generator.- When the generator voltage (o r power supply voltage) gets high enough the DMR-200 will turn on and conne ct GEN to MAIN.- Yours did this, and it is normal. =0A=0AOnce connected, the job of the device is to disconnect GEN from MAINS only if it sees rever se current flowing from the MAINS back to the GEN.- Which would be the ca se if the generator stopped spinning or failed.- =0A=0AANYWAY... what you are SEEING is normal, but is not quite the way it works in the aircraft, b asically because your test setup power supply is not allowing reverse curre nt.- =0A=0AI am going by memory on all of this and need to see the diagra m again, but I think ... and I need to check this... but I think if you dis connect the jumper you have from B to +,- the device should OPEN and disc onnect GEN from MAINS.- I need to check that, but I will get back to you on it.- I could be wrong on that, and will get back to you on that-by t omorrow.- =0A=0AMark Bitterlich=0A=0A=0A=0A=0A___________________________ _____=0AFrom: shahnow =0ATo: yak-list@matronics.com=0AS ent: Tuesday, May 19, 2009 9:26:56 PM=0ASubject: Yak-List: Re: White Paper =0A=0AHi All,=0A=0AI have a situation with Mi-17-1V Rus sian Aircraft whereby when pilot switch off all the generators after flight , I found that the combine device DMR-200D still combining Rectifier Bus an d Battery Bus.=0A=0AI have test the DMR-200D to simulate as per on Aircraft operation. The "B" is shorted to "+" terminal, "-" connected to ground, 'M AINS' connected to Battery +24V, 'GEN' connected to DC Supply +28V.=0A=0AI run the test. after put in the DC supply +28V, the DMR-200D combine the DC supply +28V with the Battery +24V. Thats mean when I measure the voltage at both terminal of 'GEN' and 'MAINS' the voltage are the same.=0A=0A=0AThen I reduce the DC Supply +28V down to 0V. I found that the DMR-200D still com bining the between the two terminal 'GEN' and 'MAINS'=0A=0AI have two new D MR-200D. I tried both and the results show same.=0A=0AMy question. Is the D MR-200D was designed to be like that? =0A=0AIs there a way to change the wi ring connection so that the DMR-200D will release the combination of 'MAINS ' to 'GEN' after we cutoff all the powers of generators of aircraft? =0A=0A Refer attachment for the wiring diagram of DMR-200D on the Mi-17-1V aircraf t.=0A=0A=0AThanks,=0AShahrul=0A=0A=0A=0A=0ARead this topic online here:=0A =0Ahttp://forums.matronics.com/viewtopic.php?p=244724#244724=0A=0A=0A=0A =0AAttachments: =0A=0Ahttp://forums.matronics.com//files/conn_of_rccr_168.p ================ ________________________________ Message 7 _____________________________________ Time: 08:45:26 PM PST US From: Yak Pilot Subject: Re: Yak-List: Interference of GPS on Becker VHF Hans, this is a much better explanation.=C2- Try this.=C2- Next time yo u go fly, leave the power lead connected for the GPS, but if possible unplu g the GPS itself while leaving the power cord connected to the aircraft.=C2 - Hopefully there is a disconnect plug at the GPS itself that would allow you to keep the GPS power cord connected with the actual GPS removed.=C2 - Also tell me what happens if you TURN THE GPS OFF in flight!=C2- Does this impact the noise in the radio with the engine running?=C2- If NOT, then for some reason your GPS power cable is either radiating noise "someho w" or is picking noise up and putting it back into wiring where it should n ot be.=C2- =0A=0AWhile unusual, this kind of thing is not unknown.=C2- =0A=0AI suggest replacing your GPS power wire with dual conductor SHIELDED wire and make sure the shield is connected to ground at the power connector side only.=C2- =0A=0AAlso, reducing RF noise from the Mags by using filt ers is never a bad idea.=C2- Before you do that, PLEASE check the P lead shields right at the MAG P LEAD CONNECTOR and make sure they are not twiste d off!=C2- That happens ALL the time, and you need to physically check th is yourself.=C2- When you unscrew the P lead connector on the mag, be SUR E to hold the center of it still as you rotate the knurled knob or you will twist the shield right off.=C2- =0A=0ABest Regards, =0A=0AMark Bitterlic h=0A=0A=C2-=0A=0A________________________________=0AFrom: Hans Oortman

=0ATo: yak-list@matronics.com=0ASent: Monday, May 18, 2009 5:12:12 AM=0ASubject: RE: Yak-List: Interference of GPS on Becker VHF=0A =0A=0AMark,=0A=C2-=0AThanks for all the good advise/suggestions. I =99ll have a look at the shieldings. When you mentioned this, I went back i n history and tried to recall when this phenoma started to occur. It is onl y since the last year and a half or so that this has become a real problem. =0AI don=99t fly a lot with gps but when I do, I need it, if you know what I mean.=0AAs far as I can recall it happened after a 100hrs check up (done by our Lithuanian mechanic). At the same time, almost 2 years ago, I used the opportunity to install an additional power connector of the Lemo t ype. These Swiss connectors are the best you can find and have a lock facil ity build in rather than the normal cigarette lighter connectors which are big and have as good as no locking facility. I use those Lemo=99s in my company for equipment we design/produce for cable companies. To make sur e that this power lead does not pick up RF, I installed a RF-choke just bef ore the connector.=0AWhen the engine is not running I hear no interference on any channel on the Becker Radio. The GPS is connected to the YAK52 =99s power and there are no problems what so ever.=0AIt is only after I sta rt the engine that the problem occurs as long as I have the GPS connected t o the planes power. When I disconnect the power lead (a long curled cable) from the planes power the problem is gone. The AvMap IV does have a RF chok e in its power lead.=0AI was under the impression that the problem was caus ed by the gps but it is the combination of the set up, i.e. engine, radio, gps, which causes this problem, not an individual piece of equipment .I think..and only when the engine is running.=0A=C2-=0AI =99ll check the shields of the p-leads on both mags. The tacho generator has already been checked and the shielding of that device is OK. =0AInstal ling these filters won=99t hurt any way, so I=99ll order them, just in case=0A=C2-=0AThanks for your help and advise!=0A=C2- =0AHans Oortman, MBA, Ph.D.=0ACEO=0ASTN BV=0A=0A___________________________ _____=0A=0AVan:owner-yak-list-server@matronics.com [mailto:owner-yak-list-s erver@matronics.com] Namens Yak Pilot=0AVerzonden: maandag 18 mei 2009 7:53 =0AAan: yak-list@matronics.com=0AOnderwerp: Re: Yak-List: Interference of G PS on Becker VHF=0A=C2-=0ALet me clarify a little here.=C2- There is a shielded P lead wire.=C2- The center conductor is soldered to a little de vice that fits into the mag itself and makes an internal connection to the mag coil.=C2- You push this into the mag P lead hole and THEN screw on th e outer shell per se.=C2- =0A=C2-=0AThe shield for this wire is soldere d to a wire CUP that fits into the screw on portion of the mag P lead conne ctor AKA "The Shell".=C2- When you screw in the P lead connector onto the mag, or OFF of the mag, it is very easy to turn the threaded portion and A LSO turn the little piece that is soldered to the shield.=C2- If you DO t urn this little piece as you screw off the threaded portion of the P lead c onnector, you will also twist the shield, and in so-doing will cause the sh ield to rip off from the connector.=C2- Thus the shield is no longer conn ected and there is no ground for it.=C2- =0A=C2-=0AIt is like MASSIVELY EASY to do this!=C2-=C2- EVERY SINGLE AIRCRAFT USING AN M-14 ENGINE I HAVE EVER SEEN HAS AT LEAST SOME DAMAGE IN THIS AREA!=C2- Every single on e.=C2- This WILL cause radio noise.=C2-=C2- Every time.=C2-=C2- ( Hans, your problem is likely something else) =0A=C2-=0AThe only way to av oid doing it is to "somehow" carefully hold that cup piece that sticks out the back of the threaded portion of the connector (the NUT per se) still as you turn the piece that screws off with your hand.=C2- I have a special tool made to do this.=C2- You can use needle nose pliers if you are caref ul.=C2-=C2- But if you ignore this advice and take off a P lead connect or... you have VERY HIGH ODDS of damaging the shield.=C2- =0A=C2-=0ARes t assured, if you didn't know this, it is even money that your P lead shiel ds are at the very minimum "damaged" if not completely broken. =0A=C2-=0A Mark=0A=0A=C2-=0A=C2-=0A=0A________________________________=0A=0AFrom:Y ak Pilot =0ATo: yak-list@matronics.com=0ASent: Monday, Ma y 18, 2009 12:47:56 AM=0ASubject: Re: Yak-List: Interference of GPS on Beck er VHF=0AOne of the most common sources of interference to radios is from t he P leads.=C2- One of the most common causes for that is the loss of a g round for the shield.=C2- The way this happens is when you unscrew the P lead connector on the mag itself, you do not also hold the shield cup on th e back of the P lead connector still as you unscrew the P lead connector it self.=C2- The result of this is that you end up twisting the shield right off the connector. =0A=C2-=0AWhen you do this, the shield is no longer g rounded.=C2- If the shield is not grounded, it will radiate noise just li ke there was no shield there to begin with and your radios will be filled w ith static and noise.=C2- =0A=C2-=0ASo, before you go out and install a ny kind of filters, ALWAYS make sure that your P LEAD shields are indeed co rrectly soldered and attached to the P lead connector itself.=C2- =0A=C2 -=0AIf everything is ok in that department and you still have noise and d ecide to try a P lead filter, install it any way you choose, but make certa in that when you are done, the P lead shield itself still has a proper grou nd on it, if not at the P lead connector itself, then in some other manner as you see fit.=C2- Do not allow the P lead wire shield "float", and keep the amount of unshielded P lead wire as short as possible when installing a filter and keep the length of the wire from the P lead shield to ground a s short as possible as well.=C2- =0A=C2-=0AAnother terrific source of n oise is the Tach Gen, and if the shield on that wire bundle breaks, the noi se can be so strong it will burn out the receiver on a Balkan 5.=C2- =0A =C2-=0AMark Bitterlich=0A=0A=C2-=0A=C2-=0A=0A________________________ ________=0A=0AFrom:Roger Kemp M.D. =0ATo: yak-list @matronics.com=0ASent: Monday, May 18, 2009 11:10:52 AM=0ASubject: RE: Yak- List: Interference of GPS on Becker VHF=0ATwo magneto filters are required. =0ADoc=0A=C2-=0AFrom:owner-yak-list-server@matronics.com [mailto:owner-ya k-list-server@matronics.com] On Behalf Of A. Dennis Savarese=0ASent: Sunday , May 17, 2009 8:26 AM=0ATo: yak-list@matronics.com=0ASubject: Re: Yak-List : Interference of GPS on Becker VHF=0A=C2-=0AYes, we installed both filte rs.=0ADennis=0A----- Original Message ----- =0AFrom:Hans Oortman =0ATo:yak- list@matronics.com =0ASent:Sunday, May 17, 2009 8:22 AM=0ASubject:RE: Yak-L ist: Interference of GPS on Becker VHF=0A=C2-=0ADennis,=0A=C2-=0ADid yo u install the in-line filter as well as the magneto filter??=0A=C2-=0AHan s=0A=C2-=0A=0A________________________________=0A=0AVan:owner-yak-list-se rver@matronics.com [mailto:owner-yak-list-server@matronics.com] Namens A. D ennis Savarese=0AVerzonden: zondag 17 mei 2009 15:03=0AAan: yak-list@matron ics.com=0AOnderwerp: Re: Yak-List: Interference of GPS on Becker VHF=0AWe r ecently had a problem with Doc's Yak 50 with noise on the Becker VHF.=C2- First we installed a nice inline filter on the DC buss; http://www.lonesta raviation.com/product_details.asp?Product_Name=The%20Eliminator.=C2- It removed much of the noise, but not all.=C2- Then we installed the magnet o filters directly on the P leads going into the magnetos.=C2- http://www .lonestaraviation.com/product_details.asp?Product_Name=Magneto%20Filter. =C2- Bingo.....noise eliminated.=C2- I mounted the ground strap to the studs on the accessory case back plate.=0ADennis=0A=C2-=0A----- Original Message ----- =0AFrom:Hans Oortman =0ATo:yak-list@matronics.com =0ASent:Sun day, May 17, 2009 7:42 AM=0ASubject:Yak-List: Interference of GPS on Becker VHF=0A=C2-=0AGuys,=0A=C2-=0AMay be some of you on the yak net has some idea how to resolve the following problem. Mark any suggestions??=0A=C2- =0AI own a Avmap IV GPS, great tool but it is getting a nuisance in the 52. =0A=C2-=0AThe following happens: when on the ground GPS switched on,=C2 -VHF on, engine NOT running, no=C2-interference on VHF at all!=0A=C2- =C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2 -=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2- =C2-=C2-=C2-=C2-=C2-=C2-=C2- when on the ground=C2-GPS swit ched on, VHF on, engine running (or in the air for that matter), huge inter ference on VHF, S5 to 6 noise level, i.e. very difficult comms. When switch ing over on battery (i.e. pulling the plug out...) the problem is as good a s gone.=0A=C2-=0AHas any body had this experience also and what have you done about it? =C2-I am thinking on a LPF or a separate DC-DC convertor f or the AvMap GPS.=0AIn principle the AvMap swallows any voltage between 10 and 36v. I assume that the 28v generator is not producing a nice DC which c auses something to start generating a noise, in my case the GPS but I do no t have an explanation for that at all....=0A=C2-=0AAny help is appreciate d!=0A=C2-=0AHans =0ARA3326K / EHSE=0A=C2-=C2-=0A =C2-=0Ahref="htt p://www.matronics.com/Navigator?Yak-List">http://www.matronhref="http://f orums.matronics.com">http://forums.matronics.com=0Ahref="http://www.matro nics.com/contribution">http://www.matronics.com/c=0A=C2-=C2-=0A =C2- =0Ahref="http://www.matronics.com/Navigator?Yak-List">http://www.matronhr ef="http://forums.matronics.com">http://forums.matronics.com=0Ahref="ht tp://www.matronics.com/contribution">http://www.matronics.com/c=0A =C2- =0A =C2-=0Ahref="http://www.matronics.com/Navigator?Yak-List">http://ww w.matronics.com/Navigator?Yak-List=0Ahref="http://forums.matronics.com">h ttp://forums.matronics.com=0Ahref="http://www.matronics.com/contribution" >http://www.matronics.com/c=0A=C2-=C2-=0A=C2- =0A=C2-=C2-=0Ahttp: //www.matronics.com/Navigator?Yak-List=0Ahttp://forums.matronics.com=0Ahttp ://www.matronics.com/contribution=0A =C2-=0Ahttp://www.matronics.com/Navi gator?Yak-Lisnics.com/contribution" target=_blank rel=nofollow>http://w ww.matronics.com/contribution=C2-=C2- =========== =C2-=C2-=C2- =0Ahttp:================ =========C2-=C2-=C2- =0A =C2-=0A =C2-=0Ahttp://ww w.matronics.com/Navigator?Yak-List=0Ahttp://forums.matronics.com=0Ahttp://w ======================== _ ===================== ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message yak-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Yak-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/yak-list Browse Digests http://www.matronics.com/digest/yak-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.