Buying guide? You mean finding one that's in one piece and the seller ISN'T asking $10,000 for it? 😂 To this day I STILL marvel at the engineering of both Tektronix and Hewlett Packard from that era. It was just magnificent.

I have three of the 575’s, all the higher voltage Mod122C models. The most expensive one was $350+ shipping. They’re well worth it IMHO. But I’m partial to the old tube 500 series Tektronix stuff.

Great Video. I replaced the readout lamps on mine - a real pain. lessons learned: use a bit of force to get the plastic lamp frame into position and put some protection around those optical fibers... the soldering iron gets damn close to them - unless there is another way :)

A buddy from my Radio club has a 575 he literally got out of the bottom of a dumpster. I have seen it left back top corner is crushed in as is the front bottom right. Despite this it still runs 100% though the variac is a little stiff.

Great video! I love these things! I had a great time repairing, restoring, and calibrating mine. Some things I would mention regarding the 576 are the following: harmonica connectors for the standard test fixture - make sure they aren't loose! Could cause a poor connection and throw you down a rabbit hole. Also be careful when removing and installing them. Don't want to break them! -i don't remember needing any high voltage/accurate capacitors for the calibration of the 576. But yes you do need some very accurate resistors! Once you get the hang of it, calibration isnt too bad! -You forgot the HV safety interlock! That safety box will likely be missing from any unit you want to buy. Which means you might have to bypass the HV interlock. That will depend on what Gen 576 you get I believe. I think the mechanisms are different. Mine is a gen 2 and used a photoelectric micro sensor (U slotted type). It was actually broke but very easy to come up with a way to bypass. In fact if you have a gen 1, the manual provides you a procedure for bypassing it! So fascinated with these instruments. Glad someone is putting plenty of great info on them out here!

I scored an HP semiconductor Analyzer which has 4 SMUs on it and provides curve tracing and many other advanced testing, I think is a better deal than those old curve tracers

There’s a cottage industry built around courrier laundering broken test equipment through eBay

Wish I had a 570.... never found one I could afford. I have a 575 and a 576... and a "parts" 576, that arrived with that switch you pointed out that can press in, pressed in... and a 7000 series plug in, 7CT1N. Had the idea that if I had a 2nd 7CT1N, I could use them in my R7844 dual beam, and overlap N and P channel devices to check for symmetry.

I used a 576 30yrs ago

I did end up purchasing that 576 from the person who wanted 1500.00 with broken/missing shaft coupler, got it for 200 bucks, I am curious about the double peaking to check the CRT as this one seems smooth, but don't know if I understand the double peaking check. This does have the black transformer and CRT with the arrows on bottom left, dates codes look like 1972, don't know what I will use it for but curious about matching components, thank you for your great videos.!

I don't know if there is, or ever was, the proper voltages to apply to the filament to burn off cathode contaminants, proper current to flash the cathode to burn off a contaminated emission layer, or proper high voltages to clean the control grids. All the info I've come across, was for CRTs used in domestic televisions. CRTs produced for Tek, were well engineered, and I double the idea of cathode poisoning due to a bad getter flash, or poor electron gun materials. Mostly a weak tube is just because it has a lot of hours on it, and most of the barium and strontium oxide, work function reducing agents, have just been evaporated away. You can't 'rejuvenate" that, but you can destroy what's left of the CRT's life... very easily.

I just got a 577 and repaired the totally messed up PS that had a previously terrible attempted repair . Got it working but have not done a calibration yet. I also have a 575 that I got over a year ago and would love a video on that. I replaced one tube on it and it somewhat works. But i have not dived into deeply into it. Any chance on doing one?

Buyers guide for these in the UK starts with a list of places you can sell your kidneys to :(

I wonder if there’s a willing and very talented, neon sign shop who can drill the CRT melt the glass to add a tube to pull vacuum. Epoxy around the stems of the metal pins that protrude through the glass. The thickness only needs to be as thick as a coat of paint to seal the vacuum leakage.. Or drilling, tap pool, vacuum and use epoxy as the method to seal the vacuum port entrance point Can be done somebody talented with using low temperature, low friction, low speed, glass drilling