HP 9114B Disk Drive Sensitive?

[Duane Hess]

Don't know about the 9114B, but certainly other disk drives have verifiable sensitivity to CRTs.

Back in the early 80s we had APPLE-IIe with dual-drive units. The dual-drives had a plastic case with no shielding. If we used the APPLE monitor they peddled with IIes, which were cosmetically designed to sit on top of the dual-drive, no issue. Other brand, don't recall what, would make the drives disfunctional.

Upon examination the APPLE brand monitors had a heavy foil glued into the bottom of the CRT case. The other brands did not. Aluminum foild in the bottom of those CRTs took care of it.

Should note in the APPLE CRT the foil "plate" was not grounded. i.e. did not have a specific ground connection. Neither did the fix for the other brand CRT.

Seems foil protection added to the CRT or drive should work. One would wonder with "wrap-around" of electric fields in the monitor whether adding protection to the sides of the device might also be possible.