While Collins Service Bulletin DME-42-34-07 addresses this optional modification, it is not feasible to perform the conversion on a -001 unit. The easiest way to perform this conversion is to change the I/O Video Circuit Card P/N 647-6678-001/002 to the -004 version. However, the 647-6678-004 is no longer available from Collins. The other way to perform this modification is to convert the -001/002 boards to be functionally equivalent to the -004 status. Unfortunately, this modification consists of replacing almost 10 parts on the -001/002 board and adding up to 22 jumper wires which then creates a very unappealing situation in the unit. Two circuit cards are made as well.

If you require DME-42 P/N 622-6263-003, Southeast Aerospace recommends simply exchanging your -001 for a -003 unit. Please contact our Part Sales dept for pricing.