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About PaulM

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  1. Back about 25 years ago I designed multichannel A/D systems for 4-20mA & TC work for general scientific datalogging. We used a platinum RTD at the reference junction, the issue isn't really cross board drift. the TC voltage differential is from where you switch from the common materials (copper) to the dissimilar metals (K, J etc) Therefore that is the back shell where the K wire is terminated into the copper pins. I would have expected the probe at the back shell to have been an RTD.. but the maint manual says that it is a K TC.. which implies that the GEA 71 has another internal reference (probably a silicon chip near the A/D), and actually has the Yellow/Red K type wire internally to just measure the refrerence point. Inline splices all depend on the temperature gradient across the splice, critical for precision work but not significant with 1500F. The airplane installations that I have seen all have one splice between the airframe wiring and the probe. If the connectors are the proper metal, then it won't be an issue. I am leery of the temperature compensation in the older analog modules.. often the EGT gauges wouldn't be compensated and that is why they are just calibrated to a peak, but I assume all of the modern digital systems get the compensation correct and are accurate to a couple of degrees.
  2. Since Don has a MVP50 it isn't the temperature compensation circuit. The G1000 uses a K thermocouple for the reference junction. I would go with the fuel getting colder and therefore more dense.. That enriches the mixture, which would lower the TIT and allow further leaning.. I will check on the next long flight if I see differences. The flow meter expects a standard density of fuel. Jets measure in lbs for this reason and their meters are mass flow devices.
  3. Don, Is your TIT gauge the original Alcor dial, or do you have a JPI digital system?
  4. Thermocouples are very reliable... if they are bouncing, then you have a bad connection in the wiring harness (CHT fluctuating).. as for the TIT probe.. check it is properly anchored, and connectors are clean/solid... (I had them bounce.. but not read so low). (pilot side, you can see it with just the upper cowl removed. ) the MP/prop/ fuel rates are on the pilot's glare shield & POH. From the POH: 32/2400 is 16-16.5... but I would assume your TIT probe is out of place but can measure peak.. so when it peaks you are at the max. 18Gph is rich.. but if the CHT's aren't complaining then you aren't too hot. I wouldn't have a problem with 15.5 at 21/2400. but you can run rich as long as the CHT's are not going high.. it is just fuel.
  5. Yes, I just ran into that... I think I'll have to find an old 2G full size sim phone... (or go to the store) my only one on hand is a original iphone locked to AT&T. I passed on my original omnipoint-->Tmobile GSM phones in 2001. Tmobile said they were specifically targeting Iot services since AT&T started the shutdown.. but obviously aren't really there for support.
  6. The t-mobile sim arrived, and worked without a problem (well, I had to call them manually to get the new phone# since they assumed you would be putting it in a phone and could just dial #NUM#. ) So, we are back online until 2020.
  7. You can run a copy of windows in a VM like virtualbox. Rumor is that the latest software for the WAAS G1000 (.34) features the geo-ref NOAA plates. I've been using the PilotPak USA on the G1000 and the mac download software, and my only issue is that I have to manually delete the old NOAA charts to clear space on the SD card before downloading the new set (MFD card only)
  8. That does look like the correct temperature probe for that unit, but it isn't a thermocouple.. It will be a RTD and I see 3 wires in the pictures. My AT&T sim went offline at 12/31/2016..(and reception had been really spotty the last 6 months as they took towers off line) So I have a t-mobile sim on order.
  9. ok.. we see that the batteries in the rocket are stuck way back there and need that magic battery board to access... are there any 12V locations in the rear? or is is cabled all the way to the front master relay?
  10. We don't quite understand this... if you are attaching it to the GPU port (in the old front battery compartment).. then the run to the battery is long now... a shorter run from the battery to the hat shelf or anything back there would be better... it will work from the GPU port.. but a shorter run (counted from the battery terminals to the charger) is what you want. The length of the additional wire must be added to the length of the wire from the connection point back to the batteries. Also.. you mention dual batteries?.. are they switched bat1/bat2? like the long bodies or are they hooked directly in parallel? 6' of charger wire is better than 2' of charger wire and 12' of airframe wire. Are there any vents/ports in the rear of that plane that could be used?.. Since it would be a K conversion I don't know if there was an o2 door in the rear.
  11. You can put it anywhere on the permanent +12V side of the battery.. so yes, the battery side of the GPU socket is fine. Battery side of the master relay is another common location. It is general practice to make the run to the battery as short as practical, but the current is low < 1.5A.. so voltage drop over larger runs is minimal. The requirement for permanent battery tender connections in aircraft is that the harness be fused. You *could* just use the GPU socket.. if you had a separate way to bootstrap the relay (9V battery). The original battery minder 28252-AA did it that way... the more recent ones had a 28v "startup" mode to trigger the relay. The standard chargers want to sense the battery before they provide current as a protection circuit. I can't find the old 28252-AA manual.. but it implied there was another version of the A2GPU plug that included a 9v battery to bootstrap the GPU relay: page 14 note. page 15 mentions a A2GPU-2 plug..
  12. Northern NJ (1N7) $475 for 40' T hangar + power .(newer ones) Waited 1 month, hangars are moved from storage use to plane use when a plane needs them. The older T-hangars are less. Self serve pump $4.40..
  13. The S55X is only connected to GIA63W #2. Swapping units #1 and #2 would show if the issue was in the GIA63W hardware. The official wiring diagram for that is 950296 (which I have not seen a copy of). But all G1000-S55x installs are the same.. so we can look at the G900 manual page F-10 Installation Manual, Rev D.pdf It would be hard to think of a reason outside of a HW failure in the GIA or wiring for why the upgrade would cause the AP problem. The connections are traditional analog GS signals and didn't change between the 63 and 63W. The tech could also go over the back shell connector and make sure that one of those 2 pins didn't get damaged. So, swap #1 and #2.. and if the problem goes away, it is a bad GIA if it doesn't go away, suspect bad connector, or wire.. I don't see a ground test procedure for the AP in approach mode. an avionics tech should be able to simulate the LOC/GS and see how the AP responds.
  14. #1 I start the 5 min timer after taxing off the runway.. #3 There is a table in the Lycoming manual (page 5-25) for setting the MP vs the injector outlet temperature. Depending on the OAT you will get between 35-38" The adjustment is very touchy and you will only hit 38" on a hot day. (not a standard day) And Lycoming has published this procedure: Density Controller Adjustment.pdf A momentary overboost is ok, due to bootstrapping surge, but that indicates that either the oil wasn't > 100 or that you were very ham fisted in the initial roll. A persistent overboost would indicate that the setting is too high and should be adjusted. (and the things DVA says)
  15. Yes, there is a Lyc, Cont difference... return piping and 2 stage pumps. I haven't had a problem starting my Bravo... but if you pre-heat the engine, remember that the timing/temps are for the engine.. which is now the CHT/Oil temp not the OAT.. On the bravo the throttle should be at the "start setting-1/4in. ", which I always leave at 1100RPM when we shutdown" (as per Dave @ All American) prime for OIL/CHT... wait a few seconds to vaporize.. then crank... I have found that if the mag timing is off (left mag is the starter mag) that it is harder to start... It is always perfect out of Annual, and then over the year can become a bit harder to start and needs more throttle.