Re: [vcf-midatlantic] Another great repair workshop
Nice work Tony, Sadly the issue with so many of the Next mono megapixel displays is that the tubes are just low emissions. Since the monitors were powered on and running as long as the machines were powered on. This was not as much of an issue with the Philips and Hitachi color monitors as they were not powered form the CPU and had a power switch and could be turned off. You can boost the screen voltage to try and compensate for that, but it is just a temporary fix. Once tubes get to a point of real low emissions even the screen voltage boost will not help, and then you just end up with a cloudy out of focus mess. Sometimes you can try a rejuvenation of the tube with a CRT tester like the Sencore CR-70 or the Sencore CR-7000 (if you have deep pockets). it is not recommended to use B&K CRT testers for their restore function as it is rather harsh and sometimes can blow the cathode apart rendering the tube useless. As of right now, there is no company that is rebuilding CRT's (but the effort to start rebuilding down in Columbus Ohio at the Early Television Museum is moving forward). So that may be an option in the next few years. On Mon, Sep 30, 2019 at 8:05 AM Tony Bogan via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
The two museum NeXT printers and two Megapixel displays are now tagged with their working state. One monitor just required a little manual adjustment and focus and is now a viable replacement for the one on display if it’s ever needed or can be used for one of the three NeXTstations VCF has if we ever display them. Both printers need work, but replacement toner cartridges are available (They use HP laserjet II or equivalent cartridges) and intake rollers can be had as well. I’ve never done it but know it’s been done before.
One monitor is working but needs some attention from the Monitor Whisperer (hi Ian!) to get the image bright enough again to be useable. I spoke with Ian and Connor at the workshop and we talked about maybe doing a NeXTfest at a future workshop to get everything working (or at least starting the process) plus bringing any of our own NeXT machines to work on as well.
Tony
-- Matt Patoray Owner, MSP Productions KD8AMG
Matt, thanks for the info. Ian has refurbed some NeXT monitors before so he’s planning on using his CRT rejuvenator. He also mentioned the power supplies getting wimpy as well. I don’t pretend to know too much about CRTs, but fortunately I know this guy Ian from VCF who has a little experience with them, or so I’ve been told ;-) Tony Sent from my iPhone
On Sep 30, 2019, at 8:35 AM, Matt Patoray via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote:
Nice work Tony, Sadly the issue with so many of the Next mono megapixel displays is that the tubes are just low emissions. Since the monitors were powered on and running as long as the machines were powered on. This was not as much of an issue with the Philips and Hitachi color monitors as they were not powered form the CPU and had a power switch and could be turned off. You can boost the screen voltage to try and compensate for that, but it is just a temporary fix. Once tubes get to a point of real low emissions even the screen voltage boost will not help, and then you just end up with a cloudy out of focus mess. Sometimes you can try a rejuvenation of the tube with a CRT tester like the Sencore CR-70 or the Sencore CR-7000 (if you have deep pockets). it is not recommended to use B&K CRT testers for their restore function as it is rather harsh and sometimes can blow the cathode apart rendering the tube useless. As of right now, there is no company that is rebuilding CRT's (but the effort to start rebuilding down in Columbus Ohio at the Early Television Museum is moving forward). So that may be an option in the next few years.
On Mon, Sep 30, 2019 at 8:05 AM Tony Bogan via vcf-midatlantic < vcf-midatlantic@lists.vcfed.org> wrote:
The two museum NeXT printers and two Megapixel displays are now tagged with their working state. One monitor just required a little manual adjustment and focus and is now a viable replacement for the one on display if it’s ever needed or can be used for one of the three NeXTstations VCF has if we ever display them. Both printers need work, but replacement toner cartridges are available (They use HP laserjet II or equivalent cartridges) and intake rollers can be had as well. I’ve never done it but know it’s been done before.
One monitor is working but needs some attention from the Monitor Whisperer (hi Ian!) to get the image bright enough again to be useable. I spoke with Ian and Connor at the workshop and we talked about maybe doing a NeXTfest at a future workshop to get everything working (or at least starting the process) plus bringing any of our own NeXT machines to work on as well.
Tony
-- Matt Patoray Owner, MSP Productions KD8AMG
participants (2)
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Matt Patoray -
Tony Bogan