| Electronics > Repair |
| W&G sna-20/23 spectrum analyzer repair |
| << < (10/20) > >> |
| alexturner:
Thanks Gerhard! So the SNA23 has two video controllers, a VGA graphics driver which is boots from, and another more advanced graphics processor which is used once the SNA software starts to drive the EL display. The issue (the Zebra lines) surfaces when the SNA software instructs the graphics card to switch and enable the EL display. I was able to validate this by running a command named BSK3 or something similar (which is the name of the graphics board). A more detailed explanation is available in the service manual. I'm still not sure what these Zebra lines are about. I'm so surprised how few people have these and know much about them. They're such wonderful examples of engineering and it's a shame that our units are destined to sit on the shelf forever until more data surfaces. At this point, I'm looking for the install disks which should be floating around the ether somewhere - sounds like you'll benefit from them too but we'll see! Alex |
| Gerhard_dk4xp:
I think the zebra banding is just uninitialized video ram; I have seen similar effects with DRAMs fresh from power up. At Leasametric they claimed a SNA33 did cost > DM100k anew, that would be > €100000 now. 26 GHz and 1 Hz resolution BW. Just build such a synthesizer. |
| Pude:
Hello everybody, I got a W&G SNA-33 from ebay yesterday and it has this problem with file system. It complains briefly about HDD controller. I already hacked a new battery for Dallas RTC and Renata battery has voltage little over 3 V. Now I'm looking for a suitable boot disk for this. The disk drive works but I'm trying to use Gotek because the ease of use. I read this thread and maybe someone of you have some boot disks to start with? This machine didn't include any of those. If so I'll like to have an image, please. I tried a normal ms-dos 6.22 boot image, but no luck. Just for fun I tried to boot from an old Red hat linux disk, but it was for a machine I've scrapped many many years ago. :) This machine does likely have flash version of C-drive. So any hints would be useful. Next I'm trying to find a keyboard for this, PS/2-kb should be fine? Some pictures below. |
| Gerhard_dk4xp:
Welcome to the club! I have made no progress in the meantime. My keyboard is an old AT02 keyboard, cloned by Cherry. Works. It is weird, that when booting it says that the c: drive is defective, but when I boot from floppy and stop the autoexec.bat early enough, I can see contents of c: Booting from what I considered a boot floppy leads to the zebra screen. Gerhard |
| Gerhard_dk4xp:
This does work also. PS2 keyboard + adapter cable. What is the bios disk type of C: on your unit? Gerhard |
| Navigation |
| Message Index |
| Next page |
| Previous page |