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], Experiments with 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], Experiments with 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], Experiments with Electron Tubes](/thumblibrary/UE3070300-230/UE3070300-230_01_140_140_Experiment-Maltese-Cross-Tube-Basic-equipment-230-V-5060-Hz.jpg)
![Set of 15 Safety Experiment Leads, 75 cm, 2.5 mm², 1002843 [U138021], Circuits](/thumblibrary/U138021/U138021_01_140_140_Set-of-15-Safety-Experiment-Leads-75-cm-25-mm.jpg)
![Tube Holder S -
for the experimental setup of tubes of series S, 1014525 [U185002], Electron Tubes S](/thumblibrary/U185002/U185002_01_140_140_Tube-Holder-S-for-the-experimental-setup-of-tubes-of-series-S.jpg)
![Helmholtz Coils S, 1000611 [U185051], Electron Tubes S](/thumblibrary/U185051/U185051_01_140_140_Helmholtz-Coils-S.jpg)
![Teltron Maltese Cross Tube S, 1000011 [U18553], Electron Tubes S](/thumblibrary/U18553/U18553_01_140_140_Teltron-Maltese-Cross-Tube-S.jpg)
![High Voltage Power Supply 5 kV (230 V, 50/60 Hz), 1003310 [U33010-230], Power Supplies](/thumblibrary/U33010-230/U33010-230_01_140_140_High-Voltage-Power-Supply-5-kV-230-V-5060-Hz.jpg)
![DC Power Supply 20 V, 5 A
(230 V, 50/60 Hz), 1003312 [U33020-230], Power Supplies](/thumblibrary/U33020-230/U33020-230_01_140_140_DC-Power-Supply-20-V-5-A-230-V-5060-Hz.jpg)