NicoN

I was asked from my partner if we (also) have an additional screen filter besides the normal oil filter. The reason for the question: In a PIPER owned by his son horrible things were found in the screen filter

I started this topic a long time ago. I simply noticed that your CDT needle did not move at all A shop diagnosed the indicator as faulty, but it was never changed. Trying to find out what to do, I simply disconnected the sensor and measured the resistance: overload. Then I shortened the wires to the instrument with master switch on - full deflection. So instrument is fine. we then replaced the sensor and CDT is working since then. My experience: during takeoff, at sea level CDT was never an issue. The needle is moving a little but never critical. The higher I climb, the more CDT is rising. I saw situation where I had to lower the power as CDT was approaching the limit temperature.

Right, we also have electrical trim but not auto-trim. So, the answer is: we need THREE servos Next question: We have 2 GI275 installed; do we ONLY need Servos (3) and a mode controller, or do we need another G5 or GI275?

I Recently changed the setting for the MISC.Field on the PFD and the HSI The PFD shows now a direction arrow and wind speed. On the HSI , I configured this MISC Field to indicate Headwind/crosswind, but this shows only two lines of dashes (in the air) The previous setting was TAS and it worked. So, I think the HSI has all necessary information it needs What is worng?

A colleague said, that the GFC500 provides vertical guidance by using the servo not direct on the elevator but using the elevator trim. Therefore he has the idea that you need 2 Servos to have lateral guidance AND vertical guidance including elevator (auto)trim. I thought you need 3

Okay, mission accomplished. Even with a newer firmware, switching between HDG and GPSS mode is not perfect. Using an external switch is way better. But the necessary details are not so easy to get. Her is what I did. 1. The switch needs to be wired to the PFD (the GI275 with ADRHS and Ap interface), not the HSI; which is nice because it is the top device 1a It needs to be a switch, not a pushbutton. The swithc connects to GND in GPSS mode, HDG mode is done when teh switch is open with a pullup-resistor. You do not need an external one. 1b I suggest, install a DPDT version, just to have something ready to drive a indicator lamp; the GI 275 has AFAIk no pin to drive a indicator lamp. 2. Find a discrete-IN pin which is not in use. 2a The discrete pins are spread over the J2751 and J2752 connector. 2b I recommend preferring the J2751 connector over the other. J2751 is the upper connector and therefore easier to access. 2c in my installation the discrete-IN on pin 62 and 63 were not in use, which makes it easier. Pins 60 to 78 are located in the upmost row and pin 60 is the rightmost (easy for people like me who have problems with numbers greater five ) 3 one pin from your switch needs to be installed in location 62 or 63. 3a make sure the pin is inserted all the way (it should not be shorter than the others) 4 the other wire from your switch can be connected to the backshell from your connector or to one of the "Aircraft ground"-pins not in use. But this is way more complicated (number greater five, you know !) 5 Next start your PFD in config mode and go down to DIAGNOSTICS - DISCRETE IN 5a There you should see something happening when flipping the switch 6 NExt go to your autopilot settings (it is way down in the INTERFACES menu) and 6a select DISCRETE instead of BUTTON 6b select the appropriate DISCRETE IN pin 7 leave the menus and power down both GI 275 7a wait 30s without power 8 power up in normal mode 9 You should see your heading bug changing from full to hollow if you flip your switch 10 install the switch. 10a I recommend to install it with the plunger to the left ( to the PFD) indicating HDG mode on and right (to the GNS430 or so) indicating GPSS. Have fun; maybe someone finds that helpful A word to the HD-pins for the 78 pin D-SUB: I was not able to find the turned pins which need this crazy expensive crimping tool. Instead, I found only those stamped ones . They can be crimped with the cheap crimping tools offering an option fro D-Sub. But it takes a good portion of experience before you make acceptable pins which can be inserted correctly. So, under all circumstances, use the turned ones!!!!

Oh yes! GI 275 and GNS430W are playing in a team. This works already. At the moment we are using the touch button on the PFD to switch between HDG mode and GPSS. But you can also put this function to an external switch.

Thank you. My posting was not precise enough. The "pull to ground" is a typical feature of all microcontrollers. INternal pullup drwas the pin to "high". If you short it to GND - fine. Both Gi 275 have some free Discrete IN- pins free for use. So, the question is - on which device do I use/wire the switch? On the PFD? Or on the HSI?

I want to have the external switch to toggle between GPSS and HDG. I found all options hpw to configure. For me the question is: On which device do I have to connect the switch to one of the Discrete inputs? PFD ? sounds logic as the toggling happens here and the PFD has the AP interface I think it is a switch between Discrete in and GND

We have a M20k with the trim switch in the left yoke horn. Also there is the MIC-Button, trim interrupt switch and we want a AP-disconnect switch. I am looking for a littel box to assemble on top to have more space for all the switches. Is there a 3D CAD model available or a pre-frabricated box? Google is PITA if you do not have the correct words to serach for

No. We still have the same problem. The GI 275s seems to work perfect - no error messages, no aligning. The heading/compass is stable and super precise, but the calibration was another nightmare with our installer. Finally we did it on our own. Last weekend I had 2 flights in F120 for 4 hours - and believe it or not: HDG mode was perfectly working at cruise altitude and failed again in low altitudes. I tested it several times and HDG mode was working with manual HDG changes and also with GPSS activated. When it was working I reached under the panel and the tray was really cold. So, maybe we have a temperature problem. I quickly made an extension cable to operate the computer off the tray, but did not try it in real life so far. Another question: has someone a schematic of the boards inside the computer available? I have the service manual but this ends always with "replace unit". For me, the upmost board drives the heading function, the middle seems to be responsible for NAV mode and the lower seems to have some power supply function and the power transistors for the motor.

I joined a Ownership for a 1980 M20K in 2018; right after all 6 cylinders had been replaced. Analyzing the old logs from our EDM830 clearly showed, that the aircraft was flown often hot if not too hot with CHT over 400°F for a longer period of time. We came along to fly LOP to save the engine's life forever. Since then we are donig this; flying LOP with 58-65% power and CHTs never over 390; in cruis we have TITs of ~1535 and FF 8.8-9.2 gals. GAMI spread is also fine Now, again 2 cyl are with low compression. Even though the exxhaust valves are looking fine. The cylsa are loosing pressure via the valves and also into the crankcase. In-place-lapping improved one cyl and had no impact on the second. Now, the shop says, our problmes are caused by flying LOP!! and he sees those problems more and more often as people flying LOP and especially in TC Mooneys and Cirrus. Okay, what to do? If Mike Busch is right propagating LOP with lower CHTs then we made everything accordingly. But if not?

That looks exactly like ours when it broke

INteresting. In fact we still have some steam gauges installed. And I don't think that they changed something with the installation of the GI275

Correct. This was an issue when the plane came back from the installer of the GI275s: They removed a DG hooked to the C21 (NOT HSI!!!!!) And obviously they did NOT change the previous jumpering . It took me a while to convince the installer that the GI 275 is "talking" always HSI and not DG. After changing that (but where exactly) the hdg mode worked just fine. That is why I am searching for the problem in the C21 and not in the wiring itself So, the question is where the wires from our GI275 really go - directly into the 1D772? Or is something in between (a magic box?). After a couple of flights my co-owners started telling me that the HDG mode is failing. As I wrote: - the ground test is always fine - even in flight the hdg mode seems to work at least for a while - I tested the hdg mode even while on ground with external power for 30 minutes (!) moving the hdg bug left and right - fine! What I cannot test on ground is if engine vibration has some negative impact. That's why I am trying to understand the vibration test. Can the diagnostic logs tell me more? So far I could not check them. Some seem password protected.