I recently purchased this TOPCON HA-3 unit off of e-bay mainly for the possibility of the RS232 and HP-IL connection capabilities. From the picture it really looks like there is an HP-71B underneath this cover. Has anyone heard of this unit?
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3082532794&category=58039&sspagename=STRK%3AMEBWN%3AIT&rd=1
Jeff