I have most VT100 family, some VT220 and VT330 parts, including all 3 colors of new VT330 CRTs.
Please contact me off list if interested. On Fri, Apr 28, 2017 at 7:27 AM, Peter Coghlan via cctalk < cctalk@classiccmp.org> wrote: > > Hi all, > > > > A colleague and I are trying to get a VT220 working again as it recently > > died on us. We are hoping to set up a few items for the mid-80s > > (including this terminal) to show the graduands what it would have been > > like if they were doing their CompSci degree 30 years ago. > > > > It looks to me like the flyback is dead. There is a lot of soot and > > there looks like there is some damage to the top of the transformer, > > better seen in the second image. > > > > http://www.cs.nott.ac.uk/~psxasj/sparse/flyback1.jpg > > http://www.cs.nott.ac.uk/~psxasj/sparse/flyback2.jpg > > > > I think the soot is fairly typical of what accumulates on high voltage > components in a city environment. I'm not sure this indicates any damage > to > it but it may well be faulty without showing any signs of damage. > > > > > The terminal powers on and does the usual beeping but nothing is > > displayed on the screen. Does anyone have any advice about what to do > > here? Are there any sources of compatible flyback transformers? > > > > I have a VT220 which also appears to have a faulty flyback. This results > in > it drawing too much current from the power supply. I am not certain the > flyback is faulty but I have eliminated most of the other components which > are likely to be responsible. > > I have looked for replacement flybacks or equivelants but I have never > found > any. Someone mentioned that they might have VT220 parts available on the > list > some time ago but I didn't get anywhere in following that up. > > > > > We have a second VT220 which exhibits the same behaviour, hopefully for > > a different reason so we can try and cobble two into one. > > > > I have a second VT220 which works and I have used it to compare readings > with my faulty one. I also tried swapping some of the suspect components > but this failed to take suspicion off the flyback. I am reluctant to try > swapping the flybacks over in case I cause damage to the working VT220. > > While the two flybacks appear likely to be electrically similar, I am not > certain of this and they are physically different - one is PCB mounted > and the other is chassis mounted with flying leads to the PCB as far as > I recall. They have different part numbers, 16-21181-01 and 16-26299-01. > > > > > Any thoughts / advice would be greatly appreciated. > > > > Sorry, I haven't been able to provide much help or hope. > > Regards, > Peter Coghlan > > > > > Thanks, > > > > Aaron. > > > > > > > > -- > > Aaron Jackson > > PhD Student, Computer Vision Laboratory > > http://cs.nott.ac.uk/~psxasj >
