Narco 890 DME question

[ben_r98]

Hello all. I am flying a Cessna 172 with a Narco 890 DME installed. The 890 seems to work great with a local vortac, but when I go xcountry it is hit and miss on other vortacs I try to pick up. Sometimes I can not fly dme approaches because of this. Sometimes I pick up a vortac, then lose it and can not pick it up any more on the flight. Any ideas why I can pick up certain vortacs and dme and not others? Thanks!

 

[kiloalpha]

Hello all. I am flying a Cessna 172 with a Narco 890 DME installed. The 890 seems to work great with a local vortac, but when I go xcountry it is hit and miss on other vortacs I try to pick up. Sometimes I can not fly dme approaches because of this. Sometimes I pick up a vortac, then lose it and can not pick it up any more on the flight. Any ideas why I can pick up certain vortacs and dme and not others? Thanks!

Sounds like it may have an antenna problem or internal circuitry problem.

It may be the absolute rare case that the VORs that are not being received are exceeding their DME service. I think only 20 aircraft can use it at once, but don't quote me on that. Since you're in SDF, I highly doubt this is the case!

 

[Barty]

Sounds like it may have an antenna problem or internal circuitry problem.

It may be the absolute rare case that the VORs that are not being received are exceeding their DME service. I think only 20 aircraft can use it at once, but don't quote me on that. Since you're in SDF, I highly doubt this is the case!

I think it is actually closer to 100.

Yes, it sounds like the DME itself has a problem. If it were the antenna, it would likely have issues with any site.