Many thanks….
Here’s the glideslope coupler drawing with interface harness:
One question about the Glide Slope Coupler Mitchell 1C493. Does anyone has a pinout of the coupler? I am just curious….
Yes Peter, I know Straubing and Mr Eckert and Mr Scheifle. I also know the pricing and timetable of Avionik Straubing (I don’t have so much money anymore and want the save a little and, by the way, it id interesting to understand “GA high tech”. I build myself 30 years ago a car telefon with self build 144 mhz and 27 mhz transmitter and receiver, so I am not unfamiliar with electronics and I am pretty sure, that there’s a Poti where I can center the heading bug (max be hidden in the KI525). May be the gain poti in the KA57 could that be, but for my understanding it is more for left right margin than center. But I will try it (it is below the panel with very short cables 😒😒😒). You said, the Heading bug is 0 volt in the center. The broken KI 825 worked fine, may be the KI 525 must be checked, may be it is a little out of limit. I will report…
I have a feeling that if the OP was content with Straubing Avionics pricing and lead times, he would not be posting here
You can simulate LOC/GS signals with an IFR4000, or some other test set, standing 10m away from the plane, but that isn’t going to exercise the heading bug / course pointer signals.
KA57 MM. Not sure if this is relevant though.
Note, any of those changes should be done in Straubing anyway, as they can simulate LOC and GS signals there on the ground while connecting all the original King analyzer hardware to the plane. Pretty interesting.
Also, assuming the KI 525a works correctly, here is a copy paste of the KA57 manual from a thread in Beechtalk. Altimatic III and Century III are assumed compatible, I couldn’t find a specific one for the Altimatic III.
Moved. One of my easier jobs here
AFAIK the heading bug from the KI525 is sent out as an analog voltage, positive and negative, with 0V being “straight ahead”. You don’t need much of a ground shift to move the zero point. But the course pointer works differently (X/Y/400Hz). If you set your GPS to OBS mode, it should display the HSI course pointer value then. Does it show the error?
I don’t really know any more than this.
Do you positively know the used KI525a is mechanically sound and ok ?
Have you slaved and de-slaved it ?
Does it turn to a new heading well, but ends up with wrong heading ?
Could be the synchros and the wiring inside the KI 525a, or may be a problem with the remote gyro. Which I assume would be a KG102 ?
I guess Martin Scheifl could tell you what to do :)
I just saw, that I took the wrong section (Hangar talk versus Avionic) Sorry for that. I will not happen again…