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Home / Physics / Modern Physics / Quantum Physics / Franck-Hertz control unit
Nobel Prize in Physics, 1925 · Franck and Hertz

Show students that atomic energy levels are real.

The classic proof of quantized energy levels, with clean, repeatable curves from mercury or neon tubes.

Franck-Hertz control unit
Franck-Hertz control unit · available in the U.S. only through American Scientific
Exclusive U.S. distributorAmerican Scientific, LLC
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Built for U.S. labs110V/60Hz, U.S. warranty and parts
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Franck-Hertz control unit
✓ Available in the U.S. 110V/60Hz Adapted U.S. Exclusive
Modern Physics / Quantum Physics

Franck-Hertz control unit

Article No. 09106-99

Compact operating unit for Franck-Hertz experiment to be used with Hg- and Ne-tubes.

Heating voltage (const.)6.5 ± 0,5 V
Acceleration voltage0...10 V (10 V ~ 100 V)
Counter voltage0...12 V
Emission voltage0...6 V
Heater voltage0...10 V
Resolution (all voltages)0.1 V
Heater current400 mA
Heater temperature0...999 °C
Anode current0...50 nA
Voltage prop. anode current0...10 V (10 V ~ 50 nA)
Data outputUSB socket
Display20 mm 7-segment LED
✓
Available in the United States, 110V/60Hz adapted for direct use in U.S. labs
★
Exclusive U.S. Distributor, American Scientific, LLC is the sole source for PHYWE products in the U.S.
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Available through American Scientific

All units adapted for 110V/60Hz. Contact us for volume pricing and grant assistance.

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Try it yourself

Sweep the accelerating voltage

Raise the voltage and watch the collector current rise, then drop, again and again. The spacing between drops is mercury's excitation energy.

Bring this to your lab →
What your students will do
1

Heat the tube

Bring the mercury or neon tube to operating temperature with the built-in heater control.

2

Sweep the voltage

Raise the accelerating voltage while the unit records the collector current at 0.1 V resolution.

3

Read the energy steps

Measure the spacing between current peaks to find the atom's excitation energy.

A great fit for
Modern PhysicsAtomic PhysicsQuantum Mechanics LabAdvanced Undergraduate Lab
4.9 eVMercury excitation energy students find
0.1 VResolution on all voltages
Hg and NeWorks with both tube types
Accelerating voltage (V)Collector current051015202530current peaks repeat every 4.9 V (mercury)

Typical Franck-Hertz curve: current peaks spaced about 4.9 V apart for mercury (illustrative).

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Planning next year's lab budget?Federal STEM and CTE grants can cover up to 100% of equipment costs. American Scientific helps you find and apply for the right one, at no charge.
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Common questions
Does it work on U.S. power?

Yes. Units supplied through American Scientific are adapted for 110V/60Hz and supported in the U.S., including warranty and replacement parts.

What else do I need to run the experiment?

Tell us about your lab in the form above and we'll put together a complete, ready-to-teach configuration, so nothing is missing on day one.

Can grant funding cover this?

Often, yes. Many institutions fund PHYWE equipment through NSF, Title IV and CTE programs, and our team can help you find and apply for the right opportunity.

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