“ The EFD1000 E5 Flight Display will replace the existing Directional Gyro or HSI in the panel. If another device is “bootstrapped” from the compass then it will need to be determined whether RS-232 or LS ARINC 429 heading is accepted by this device and rewired appropriately. If the other device only accepts ARINC 407 synchro heading or HS ARINC 429 then an ACU2 will be required.”
Does anybody know if a KI229 can be “bootstrapped” to an Aspen E5 ? I’m not familiar with these communication protocols.
The 229 gets its directional info from the BK HSI. I’m hoping it will accept magnetic hdg from the Aspen as well…
airways wrote:
Does anybody know if a KI229 can be “bootstrapped” to an Aspen E5 ? I’m not familiar with these communication protocols.
You will need the ACU2. The KI229 requires an ARINC 407 synchro input – it has no serial heading interface. The ACU2 will also provide the 400Hz reference signal but only to one external device.
That’s the answer I was looking for. Thank you @wigglyamp. Unfortunately the ACU2 is rather expensive. Not sure it is worth it…
I used to have a KI229 RMI in the TB20. It is a “dumb” product (no CPU, no serial comms). It takes in the bearing data via X/Y/400Hz.
In the classic KCS55 slaved compass system, the KG102A doesn’t have enough drive to drive both a KI525 HSI and a KI229 RMI, and a separate 400Hz inverter is needed (usually the crappy unreliable MD26-28). The MD26 then supplies 400Hz to the KG102A, I think. I don’t know if this is relevant to the Aspec context but you can pick up an MD28-28 from US Ebay for not much.
usually the crappy unreliable MD26-28
Better to put that money towards an ACU 2 then.
Unfortunately I can’t answer that without wading through a load of circuits which I last saw in 2013, but I think the answer is Yes. The KI229 gets the bearing from the KG102A, the ADF needle comes from a KR87 ADF or some such, and the VOR needle comes from a box like a KN72 which takes the composite nav signal from a KX radio and converts it to a X/Y/400Hz format. So the KI525 HSI probably doesn’t do anything for the KI229.
On my plane I replaced the KI525, the KI229, the KA52 slaving accessory and the MD26 with the Sandel SN3500, and 1 year later replaced the KG102A and the fluxgate with the Sandel SG102 AHRS. It’s really high grade stuff but probably few are interested in using it for a new installation, because it’s not cheap. That said, I see a lot of these coming up on US Ebay as people put in “all glass”.
That would be great. I have no problem keeping the ADF but I don’t want to pour any additional money in its operation.
airways wrote:
can you remove the KI525 without losing the functionality of the RMI (leave the KI102A, lose the KI525)
No you can’t. The heading bootstrap synchro which sends the data to the RMI is inside the KI525A.
Bugger :-/
