[ARC5] [Milsurplus] " ZA Instrument Landing Check-Off List " Also AN/ARN-9.

[Jack Antonio]

> On 11/3/2017 5:58 PM, Mike Morrow wrote:
>> Jack Antonio has put together what is likely the only complete ZA 
>> "Air-Track" ILS set anywhere in the world.
>
> There *must* be another complete set out there somewhere.  My set is a 
> composite of pieces from many sources
> (thanks to Mike Morrow for at least one of the pieces), and the 
> control box is unwired, due to a previous owners
> repurposing it. It is on the project list to build up the set as a 
> display item,  but I probably won't attempt to make
> it operational. Once I get my RC-103 system put together, I'll 
> probably put the ZA together as a comparison
> display.
>
> Jeep asked about channelization. I have seen no information on how 
> specific frequencies were assigned to this system. The glide slope
> receiver is tunable, but looks like it was meant to be fixed tuned to 
> a specific frequency and not retuned  during flight. The localizer
> used a LF/MF receiver, (RU is mentioned in the manual, but I've seen 
> references for use with an RAX and ARC-5), so could be retuned
> to a specific station. But exactly how all this worked out in 
> practice, I don't know.
>
> The localizer function did use 90 and 150 cycles, but the glide slope 
> was a single beam type system. The glide slope
> indicator was for all intents and purposes just a field strength 
> meter. The glide slope was determined by following a
> constant signal strength curve, underneath the main lobe of the ground 
> station transmit antenna.  I think a lot
> of the setup procedure was to insure that the airplane was underneath 
> the beam.
>
> Jack Antonio
> WA7DIA
>
>