5

Most, if not all, old HP spectrum analyzers say

X-Rays generated in this intsr are sufficiently screened

Why do they generate x-rays at all. The HP 8565E I am looking at can only measure up to 50 GHz so I have trouble seeing why it would have such high frequencies in it.

Brian Carlton
  • 13,252
  • 5
  • 43
  • 64
  • 3
    Off the top of my head, it could be the CRT. – Sredni Vashtar Feb 24 '17 at 01:44
  • 2
    @SredniVashtar has it, it's the old CRT. That's why they used to advise not sitting close to the old television sets. – John D Feb 24 '17 at 02:06
  • @JohnD now I'll want to find a similar vintage logic analyzer and see if it has a similar notice. – Brian Carlton Feb 24 '17 at 02:24
  • Thick Leaded faceglass in the CRT blocks the X-Rays from current of higher voltage accelerated electrons hitting the screen. In software we called the * symbol the "splat key"m which is what happens when you sent a dot hurled at the screen. It goes "splat" *. In TV's XRays are created by HiV charged atoms smashing into the shadow mask/aperture grille and phosphors. This creates a flow of static as well outside the screen but is not an indication of XRays. – Tony Stewart EE75 Feb 24 '17 at 03:56
  • Is that "are sufficiently screened" as you've written? **Sounds to me they are saying not to worry**. In the old tube TVs that I used to cart home as a kid (for the parts), the warning was on the cage surrounding the HV rectifier tube. – Mike Waters Feb 24 '17 at 15:16

1 Answers1

9

The warning relates to the display, not the instrument itself.

The HP 8565E uses a CRT monitor as its display. CRTs are electron beam devices, and can emit some X-rays if improperly adjusted and/or inadequately shielded. The notice is reassuring you that the hardware limits on brightness, and the leaded glass built into the screen, are sufficient to protect you from exposure.

This sort of notice is normal for devices containing CRTs; You'll probably find similar notices buried in the manuals of old televisions and computer monitors.