[Milsurplus] R-249/APN-9A modified R-65A/APN-9 adding mechanical digital time delay readout

[Boeing377 via Milsurplus]

Any ex military navs or aircrew ever see one of these? It was a major mod of the familiar R 65/APN-9 adding the ability to get a direct TD readout on a Veeder Root counter rather than manually counting timing pips on the CRT face. 



https://sites.google.com/site/apn9andpostwarvariants/


I can't find a single USAF vet who ever saw a R-249/APN-9A  much less used it for navigation. Some questioned its existence until I found these pics on eBay.


Mark
AF6IM