Cathode rays and deflecting fields can be used to magnify shadow images in a manner analogous to an optical lens system.
With the help of this supplement, the experiment: Maltese-Cross Tube (item no: UE3070300-230 / 8000660) is modified in such a way that the following electron-optical observations can be made:
By increasing the magnetic field (raising the voltage to the coil) the image is seen to rotate, diminish to a spot and then enlarge again in inverted form.
Anode voltage variations provide a further element of control.
![Experiment: Maltese-Cross Tube, Supplement (230 V, 50/60 Hz), 8000662 [UE3070300S-230], Electron tubes](/imagelibrary/UE3070300S-230/UE3070300S-230_01_Experiment-Maltese-Cross-Tube-Supplement-230-V-5060-Hz.jpg)
![Experiment: Maltese-Cross Tube, Supplement (230 V, 50/60 Hz), 8000662 [UE3070300S-230], Electron tubes](/thumblibrary/UE3070300S-230/UE3070300S-230_01_1200_1200_Experiment-Maltese-Cross-Tube-Supplement-230-V-5060-Hz.jpg)
![Experiment: Maltese-Cross Tube, Basic equipment (230 V, 50/60 Hz), 8000660 [UE3070300-230], 电子管的实验](/thumblibrary/UE3070300-230/UE3070300-230_01_140_140_Experiment-Maltese-Cross-Tube-Basic-equipment-230-V-5060-Hz.jpg)
![15根安全实验导线套件，75mm, 1002843 [U138021], 电循环](/thumblibrary/U138021/U138021_01_140_140_15根安全实验导线套件-75mm.jpg)
![Teltron 管座 S, 1014525 [U185002], 电子管 S](/thumblibrary/U185002/U185002_01_140_140_Teltron-管座-S.jpg)
![Teltron亥姆霍兹线圈S, 1000611 [U185051], 电子管S](/thumblibrary/U185051/U185051_01_140_140_Teltron亥姆霍兹线圈S.jpg)
![马尔他十字形管, 1000011 [U18553], 电子管S](/thumblibrary/U18553/U18553_01_140_140_马尔他十字形管.jpg)
![高压电源5kV（230 V，50/60 Hz）, 1003310 [U33010-230], 供电器](/thumblibrary/U33010-230/U33010-230_01_140_140_高压电源5kV-230-V-5060-Hz.jpg)
![直流电源0 – 20 V, 0 – 5 A
(230 V, 50/60 Hz), 1003312 [U33020-230], 供电器](/thumblibrary/U33020-230/U33020-230_01_140_140_直流电源0-20-V-0-5-A-230-V-5060-Hz.jpg)