Building a Modern CRT Analyzer/Rejuvenator to Replace Aging Testers - Looking for Expert Feedback

[aveesry]

Hey everyone!
I'm an electrical/mechanical engineering student and for my 2026 major project I'm planning to design and build a modernized CRT Analyzer + Rejuvenator inspired by the Sencore CR7000 but rebuilt with modern components, safer architecture and far more flexible features.

Before I dive too deep into the design I want to get real input from the people who actually use this stuff. I'd love to hear what features matter most to you, what frustrations you've had with older testers, and what would genuinely make a new, modern unit worth owning.

If you can answer any (or all) of the questions, it would help massively. It should on take a few minutes
https://forms.gle/Q5AGyZGFKLTDkZVz8

 

[Marquee Mark]

What a first post! Best of luck with the build!

 

[joemagiera]

Subscribed!

Very interested. Location? School? Background that led you to this particular selection of a project?

 

[SNESNESCUBE64]

Interesting project. I'd love to see your take once ya finish the project. I filled out the form.

 

[64B1T]

Subscribed to this. Seems interesting! Filled out the form.

Here's a couple ideas for ya (I started writing this before I filled out the form and noticed you had a couple of these down already)

• Make whatever you're building compatible with B&K tube adapters.
• In the vein of the B&K 467, make each gun readout available simultaneously through the digital display you mentioned.
• Integrate the device with https://tubular.atomized.org/ It would be sweet to just punch in a tube number and have the voltage settings automatically configured and have the requested adapter pop up.
• If you want to get really fancy, build in an "auto mode" given that most procedures are conditional, i.e. "press button until x happens on readout" which should be easy for a computer to detect.

 

[aveesry]

Subscribed!

Very interested. Location? School? Background that led you to this particular selection of a project?

It's definitely going to be a bit of a work-in-progress and I'm hoping to have most of the planning/design stage wrapped up by March. I'm based down under in Australia. Right now I'm undertaking a certification in machining and mechanical engineering and I've already completed my fabrication certification. On the electrical side I'm currently undertaking my bachelor's.

A lot of people have mentioned documentation so here's the plan so far:
I'll be producing multiple documentation sets: a standard user manual with simple setup guides and safety info + deeper explanations of theory and operation for people who want the technical side. I'll also be making my full project write-up/paper (the one I have to submit for my degree) publicly available once it's complete. There will absolutely be a GitHub repo and full schematics but those won't be released until the project is nearing completion.

From the early feedback it looks like I'll be including built-in modes for popular tubes and I'm considering integration with Tubular. That said I want the device to work offline by default no login, no cloud, no internet dependency because that's one of my biggest gripes with a lot of modern test equipment.

Once I close the form in about a week I'll have a much clearer picture of what the community actually wants. I'll share the refined feature list, get another round of feedback and then start the actual device design phase.
Just a heads-up that since this project is part of my degree there will be stretches where I have to focus on other academic work. The planning stage will also be quite long because I need to follow the proper engineering and academic process. But the upside is that this should result in a very high-quality design - something built to last, well-documented and engineered to a standard I can stand behind for a long time to come.

 

[pat9000]

There probably isn't really much "need" to automate much of the process beyond time-limiting some restoration current as you ultimately just need to have some experience using these boxes to know how far you should push things with a given tube's behavior.

And stepping back even further, the majority of tubes newer than mid '80s generally won't respond well to anything beyond the mildest efforts to improve emission. E.G. if a 25" tube has poor emission they are almost never salvageable for anything beyond occasional use for months/year if you're lucky - you're best off just hunting for a TV swap.

If you're looking to build a box with the best features from what's out there you'll want to focus on features of the CR7000 and the 490B.
The B&K 490B is different from all B&K previous designs as it's a re-branded Konig TR-851, but it has automated restoration routines unlike those of anything else found in USA. Read the manual for it and I think it goes over the basics.

I'd also look into these, though we're unfamiliar with them in USA:

Müter BMR-95 & 2005 CRT Testers | CRT Database

Table of Contents Overview Key Features Buyer's Guide...

crtdatabase.com

The CR7000 has some varying levels of restoration current application available, but most importantly it has a 30-sec 1ma "reactivate" feature that is always the best starting point - if you can get good results from this on a newer tube it'll tend to last a while. No other box has this and it's basically the reason why everybody should only be using a CR7000. Or somebody should at least come up with a ~1ma mod circuit you can hack-in/add a switch for on older B&Ks.

If you're only working on 4600//4900/GO7 you're probably fine with a cheap older B&K anyway as the electron guns in those tubes can handle more abuse.

http://nestreble.ca/Sencore/SencoreNews185%20-%20CR7000.pdf

 

[aveesry]

First update! The form is now closed and I have began designing the first version of the specs, design principals, ect, ect. Thank you to everyone who replied to it!