KRviator
Well Known Member
'Evening all.
Given the Australian Gumby-ment made the decision to withdraw the vast majority of our ground-based navigation aids down here has meant we are now transitioning primarily to GNSS-based Nav sources down under.
As I don't require the capability a G430 will give me and a GTN is out of the question until the kids move out in another 15 years time, I looked around and found the KLN-90B will talk to SkyView using the ARINC module. After a month or so watching Ebay, I found one for $500 and snapped it up. Now bear in mind this is a 20-year-old GPS so it won't make you coffee in flight, and it is lucky to have a rudimentary moving-map display, but by all accounts it is a pretty good unit once you get over the learning curve. Read the manual, plug it in at home and it is fairly easy once you understand the dual-concentric knobs and menu structure.
The KLN-90B at home. Green-screen. Very retro...
But, like most panel-mount navigators, it will often require an external annunciator panel, to relay some indications and give you the option to switch between modes on the fly. Pardon the pun. Ahem.
After seeing Spruce and the usual vendors wanted megadollars for a Mid-Continent annunciator panel, I looked through the installation manual and decided I could make my own quite easily. So, with a little headscratching, and a temporary bracket, here is the result on the test bench (aka the dinner table):
The left switch indicates the approach status, Active or Armed, and is a DPST momentary switch that will alternate between these two modes when pressed, by grounding the relevant pin on the KLN.
The right switch currently indicates Message and Waypoint Transition, and pressing this switch will alternate between OBS and LEG modes on the GPS. For some reason I thought the KLN required an external LEG/OBS annunciator, but it only required an external switch to change these two modes. So V2 will have a replacement actuator for this particular switch and will combine MSG/WPT functions into the top LED and have the bottom LED permanently illuminated showing the LEG/OBS text.
Total cost for the GPS, 3 switches and custom actuators was $600 AUD. The switches are Carling part #: VBD2YNHB that translates into a DPST Momentary switch, with two independent LED's. This is important as most switches have 1 independent light and 1 dependent, the difference being the dependent one is only illuminated when the circuit is active. With both being independent, they can be driven by the KLN-90B. They came from Spemco, the custom actuators came from RockerSwitchPros.
Now, for those in the US and Canada where you have the option of LPV approaches, a GNS-430W is an attractive option, so having such a simple C129 GPS doesn't make an awful lot of sense unless you supplement it with VOR/ILS capability in another unit. But for those down here, and elsewhere, something like this might give you a fairly cheap approach capability. IT also isn't limited to the KLN series, a bloke on the Dynon forums has done a very similar thing with a Garmin 300XL.
Given the Australian Gumby-ment made the decision to withdraw the vast majority of our ground-based navigation aids down here has meant we are now transitioning primarily to GNSS-based Nav sources down under.
As I don't require the capability a G430 will give me and a GTN is out of the question until the kids move out in another 15 years time, I looked around and found the KLN-90B will talk to SkyView using the ARINC module. After a month or so watching Ebay, I found one for $500 and snapped it up. Now bear in mind this is a 20-year-old GPS so it won't make you coffee in flight, and it is lucky to have a rudimentary moving-map display, but by all accounts it is a pretty good unit once you get over the learning curve. Read the manual, plug it in at home and it is fairly easy once you understand the dual-concentric knobs and menu structure.
The KLN-90B at home. Green-screen. Very retro...
But, like most panel-mount navigators, it will often require an external annunciator panel, to relay some indications and give you the option to switch between modes on the fly. Pardon the pun. Ahem.
After seeing Spruce and the usual vendors wanted megadollars for a Mid-Continent annunciator panel, I looked through the installation manual and decided I could make my own quite easily. So, with a little headscratching, and a temporary bracket, here is the result on the test bench (aka the dinner table):
The left switch indicates the approach status, Active or Armed, and is a DPST momentary switch that will alternate between these two modes when pressed, by grounding the relevant pin on the KLN.
The right switch currently indicates Message and Waypoint Transition, and pressing this switch will alternate between OBS and LEG modes on the GPS. For some reason I thought the KLN required an external LEG/OBS annunciator, but it only required an external switch to change these two modes. So V2 will have a replacement actuator for this particular switch and will combine MSG/WPT functions into the top LED and have the bottom LED permanently illuminated showing the LEG/OBS text.
Total cost for the GPS, 3 switches and custom actuators was $600 AUD. The switches are Carling part #: VBD2YNHB that translates into a DPST Momentary switch, with two independent LED's. This is important as most switches have 1 independent light and 1 dependent, the difference being the dependent one is only illuminated when the circuit is active. With both being independent, they can be driven by the KLN-90B. They came from Spemco, the custom actuators came from RockerSwitchPros.
Now, for those in the US and Canada where you have the option of LPV approaches, a GNS-430W is an attractive option, so having such a simple C129 GPS doesn't make an awful lot of sense unless you supplement it with VOR/ILS capability in another unit. But for those down here, and elsewhere, something like this might give you a fairly cheap approach capability. IT also isn't limited to the KLN series, a bloke on the Dynon forums has done a very similar thing with a Garmin 300XL.
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