Yokogawa VN7100 Linux SW recovery. - Page 1
Forum section: electronics / testgear

author: nonlinear
author_rank: Contributor
timestamp: May 19, 2018, 04:55:54 pm
content: Hello.Got the damaged unit.Rare case - its repair required mechanical, electronic and finally SW repair.1. Unit got strong hit to N connector. Disassembling, careful bending, ...2. RF block failed calibration. Spring RF coil had bad contact in 1-st LO PLL module so YIG was unlocked w/o sampler power.3. SW problem which was caused by my actions - aAfter several hard power-offs during RF block repair (SW did not shutdown as it hang with broken RF block) Ext3 FS on the internal CF card was totally destroyed. Had to copy it before repairs.FS destruction was so massive that even directory structure could not be recovered.Maybe somebody has a backup image oа this 512MB CF card or SW distribution?

author: PE1RQF
author_rank: Newbie
timestamp: May 07, 2021, 07:34:21 am
content: Hi, I have a working Yokogawa VN7100.Still need help?Erik

author: kcbrown
author_rank: Frequent Contributor
timestamp: May 08, 2021, 12:25:17 am
content: Yikes.I guess the moral of the story is: if you're about to attempt repair of an instrument that has a hard drive, take an image copy of the hard drivebefore doing anything else!

author: Trader
author_rank: Frequent Contributor
timestamp: May 08, 2021, 03:12:53 am
content: 3 years... did you fix it?

author: nonlinear
author_rank: Contributor
timestamp: May 09, 2021, 07:52:09 pm
content: Hi.No, unit is still not fixed. Will be very grateful for disk image or any other variant of backup.Initial boot problem was some damage of Ext3 master block which changed disk geometry.This resulted in Ext3 journal pieces randomly written to the disk.I had experience with FAT filesystem recovery procedures so I read manuals on Ext3structure and spent a lot of time in disk editor finding and linking directories to inodes,copying sectors, ...I found deleted SW distribution archive on the second HDD and parts of it copied to СF card.Was able to recover it from pieces so I had the SW.Found Bash command history with a lot of commands which were issued on new unit toinstall SW for the first time.Recovered /etc directory and some other directories.Installed appropriate, clean Redhat version and did my best to apply everythingrecovered there.Now SW starts, sees no keys / serial number, draws main screen with calibrationand then writes "fan error - shutting down".Fans are OK so SW cannot access the sensors. Suspect that sensors are in UARTson the motherboard and keys are also there. So think problem is in accessing UARTsfrom the SW. Maybe some settings are missing.

author: PE1RQF
author_rank: Newbie
timestamp: May 14, 2021, 05:40:15 pm
content: Hi, I can try to make a copy of the image 512MB CF card from my instrument?regards,Erik

author: nonlinear
author_rank: Contributor
timestamp: May 14, 2021, 06:39:08 pm
content: HI, Erik.Will be very grateful if you do that. You will also have the copy in case of CF fault.My raw CF image (full, per-sector copy of sectors 0-100000) madewith disk editor (program called Dmde) is ~188 Mbytes, if ZIPped.Thank you.Nonlinear

author: PE1RQF
author_rank: Newbie
timestamp: May 19, 2021, 05:59:40 pm
content: I will give it a try next week.Erik