It appears that those surplus elements (let's call it the "comma position") light up if and only if that same position is ever *correctly illuminated anywhere else* on the display. That position (either a "row" or a "column" in the multiplexed matrix) may have a dodgy connection.
You could be on to something as is Bob. But it's beyond me and I'm now getting bored with it! It fills me with fear taking the whole thing apart at the moment, but maybe when I'm feeling more confident. Chances of getting a new display seem slim. It appears Tektronix stopped supplying them several years ago.
nice acquisition Nick, those Kithley are nice but they cost an arm and a leg. Even with minor issues is a nice add on to your workshop. Hopefully you can find the reason for those ghost segments on the display at least. All the best Diego
Hi Diego, its taken me a long time to find one of these at an affordable price, but of course that reflects its problems. I think its highly unlikely I can find a new display for it. I've been down a few "rabbit holes" searching for one. But its still quite useable as it is. I can find no schematics for it making it even more difficult. So I will use it as it is. You can still buy the 2015 new. Only $8000!
Hi Nick. After yesterday's comment it occurred to me that those extra segments light when the segment in the same position in the V position on the display is turned on. So whenever you make a selection on the front panel which means that segment in that digit/character position is driven then those extra segments on other digits light up. I don't know how well I've just expressed what I wanted to say but it almost feels as though whatever bit of electronics is driving that segment is ringing so that when the circuit is asked to drive the next digit (assuming here that each digit, or possibly pairs of digits, is driven sequentially from right to left) it may carry a memory of what it just did. I may be wrong and it might not help in fixing the problem but if I'm right then maybe, just maybe, if Tektronix comes through you'll cure both the segment and brightness issues. Fingers crossed.
Hi Bob, I think you expressed it quite well, although I had to read your comment several times for it to sink in. Whatever the problem is I don't think its something I can fix, especially with no schematics available. Highly unlikely I will get a new display. It appears tektronix stopped supplying them several years ago. I'm surprised someone hasn't made a modern version as there must be thousands out there that need a new display. Thanks for all your comments, much appreciated
Hi Danish, heard from tektronix, they won't sell me a display. But they will happily service it for me. No thanks, they would probably charge more that I paid for it!
To be fair, can't argue with that at all. If it were one of the digit elements, and corrupted a reading, then that'd be different. Surplus commas, well, we're not being graded by an English teacher.
@@matambale Doesn't look like he has much choice. Tek apparently snubbed him. Not many of these for sale on Evil Bay at extortion prices. Only hope is to maybe find a donor at some point in the future and that doesn't look likely either. Also VFD fade from cathode emission loss is a well known issue....nuttin' lasts forever 😪
It appears that those surplus elements (let's call it the "comma position") light up if and only if that same position is ever *correctly illuminated anywhere else* on the display. That position (either a "row" or a "column" in the multiplexed matrix) may have a dodgy connection.
You could be on to something as is Bob. But it's beyond me and I'm now getting bored with it! It fills me with fear taking the whole thing apart at the moment, but maybe when I'm feeling more confident. Chances of getting a new display seem slim. It appears Tektronix stopped supplying them several years ago.
nice acquisition Nick, those Kithley are nice but they cost an arm and a leg. Even with minor issues is a nice add on to your workshop. Hopefully you can find the reason for those ghost segments on the display at least.
All the best
Diego
Hi Diego, its taken me a long time to find one of these at an affordable price, but of course that reflects its problems. I think its highly unlikely I can find a new display for it. I've been down a few "rabbit holes" searching for one. But its still quite useable as it is. I can find no schematics for it making it even more difficult. So I will use it as it is. You can still buy the 2015 new. Only $8000!
Hi Nick. After yesterday's comment it occurred to me that those extra segments light when the segment in the same position in the V position on the display is turned on. So whenever you make a selection on the front panel which means that segment in that digit/character position is driven then those extra segments on other digits light up. I don't know how well I've just expressed what I wanted to say but it almost feels as though whatever bit of electronics is driving that segment is ringing so that when the circuit is asked to drive the next digit (assuming here that each digit, or possibly pairs of digits, is driven sequentially from right to left) it may carry a memory of what it just did. I may be wrong and it might not help in fixing the problem but if I'm right then maybe, just maybe, if Tektronix comes through you'll cure both the segment and brightness issues. Fingers crossed.
Hi Bob, I think you expressed it quite well, although I had to read your comment several times for it to sink in. Whatever the problem is I don't think its something I can fix, especially with no schematics available. Highly unlikely I will get a new display. It appears tektronix stopped supplying them several years ago. I'm surprised someone hasn't made a modern version as there must be thousands out there that need a new display.
Thanks for all your comments, much appreciated
Ignore the Ghost bits. Looks like it works and reasonable cal for now. Cheers.
Hi Danish, heard from tektronix, they won't sell me a display. But they will happily service it for me. No thanks, they would probably charge more that I paid for it!
To be fair, can't argue with that at all. If it were one of the digit elements, and corrupted a reading, then that'd be different. Surplus commas, well, we're not being graded by an English teacher.
@@matambale Doesn't look like he has much choice. Tek apparently snubbed him. Not many of these for sale on Evil Bay at extortion prices. Only hope is to maybe find a donor at some point in the future and that doesn't look likely either. Also VFD fade from cathode emission loss is a well known issue....nuttin' lasts forever 😪