2021-08-13 21:22:35 UTC
OpenVMS IA64 HPE V8.4 running NDC Compufax. We have been working with NDC. The site has four faxmodems (Multitech ZDX series) that were running off of a DECserver 200 (now deceased). We dropped in a DECserver 700-08 running the pre-DNAS V1.5 firmware using identical port settings, and while it works we're getting complaints about quality issues on the receiving end; we've confirmed this is a send-side issue, not line or recipient. Currently testing to a real fax machine at the site but the hashing and lines we get there perfectly match what some customers scanned and emailed back to us.
If so this is the first time we've had a situation where a DS700-08 brought in problems when replacing a DS200-MC
NDC had us try a delay logical that introduces a small delay between sending lines (value between 1 and 'unknown' but we tested a range between 1 and 200). We see minor changes in the output but quality issues remain the same. If you send the same textfile several times with the same delay factor (or none) the output is identical; same hashing and streaking on the page except for one (so far) delay value that was cleaner but dropped entire scanlines. NDC has notes that this delay option was put in for DECserver 700s.
We can put DNAS on this DECserver instead of the older firmware; it is a non flash model but with 4MB RAM. We may be able to sub a DS90M also but would have to fabricate cables.
Anyone recall if there's tweaks we could make on the DECserver itself, old or DNAS firmware, to change its flow control response speed (sort of like DELAY_ACK on the TCPIP front)? Or perhaps recall having issues like this before? I really don't want to try to find a working DS200 MC.
Yes, alternatives like using a mail-out fax service may be considered but for now we need this working properly again.