Pencil Jockey for lab
Product Code : SCL-EAE-12117
Pencil Jockey for lab (SKU SCL-EAE-12117) is a pen-shaped contact probe for making a temporary sliding connection on the resistance wire of a meter bridge, potentiometer or slide wire. Its insulated handle and plated brass knife-edge let Class 12 and college students find the null point without gripping bare metal. Science Lab Supplies makes the jockey at its Plot 448 factory in the HSIIDC Industrial Area, Saha, Ambala, India, and supplies schools, colleges, tender contractors and distributors directly as the manufacturer.
Specifications
Each specification of the jockey appears as a row in the table below. In short, it is an insulated plastic or ebonite pen-style body about 100 mm long, tipped with a plated brass knife-edge and fitted at the top with a 4 mm safety socket that takes standard banana-plug leads.
| Specification | Value |
|---|---|
| SKU | SCL-EAE-12117 |
| Type | Pen-shaped sliding contact jockey |
| Handle material | Heavy-duty insulated plastic / ebonite |
| Contact tip | Plated brass, sharp knife-edge |
| Terminal | 1 x 4 mm safety socket at the top end |
| Lead compatibility | Standard 4 mm banana-plug leads and patch cords |
| Total length | Approx. 100 mm |
| Suitable wires | Manganin or constantan resistance wires |
| Compatibility | Potentiometers, meter bridges and slide wires |
| Tip protection | Protective tip cap for storage |
| Manufacturer | Science Lab Supplies, Saha, Ambala, Haryana |
| Country of origin | India |
Applications and Experiments for the Pencil Jockey
The jockey carries the galvanometer lead to any point on a bridge or potentiometer wire. Students press the knife-edge gently on the wire, move it until the galvanometer shows zero deflection and read the balancing length from the scale, a routine step in school physics lab equipment practicals in India.
- Class 12 physics: resistance and resistivity of a wire on the Meter Bridge or Wheatstone Bridge.
- Comparing the EMFs of two primary cells on a Potentiometer with Jockey Pencil.
- Internal resistance of a cell and other potentiometer balance methods.
- B.Sc. physics: measuring low unknown resistances by the null method, with a centre-zero galvanometer such as the Galvanometer 30-0-30 mA.
Use only light pressure: scraping or pressing hard flattens or kinks the wire and shifts later readings. Lift and touch rather than drag where possible.
Standard Scope of Supply
Each pack contains one Pencil Jockey for lab with its integrated 4 mm socket terminal and one protective tip cap for safe storage. Connecting leads, the bridge or potentiometer and the galvanometer are separate items and can be listed on the same quotation as the jockeys.
Packing, MOQ and Lead Time
Jockeys can be quoted singly as spares or in sets for every meter bridge and potentiometer in the lab. The quotation shows the packing, delivery time and price for the number you ask for, and the bridges, keys and galvanometers they work with can be priced on the same page.
As the holder of an Importer-Exporter Code, Science Lab Supplies can ship to buyers in Vietnam, Malaysia, Peru, Egypt, Iraq and Nigeria. Send quantities via the contact page, add them to the enquiry cart, or refer tender documents to the lab tender page.
Frequently Asked Questions
Why is it called a pencil jockey?
Its slim, pen-like body is held like a pencil, which gives fine control when moving the contact along the wire in small steps to locate the exact balance point on a bridge or potentiometer.
Which leads fit the jockey?
The top carries a 4 mm safety socket, so standard 4 mm banana-plug test leads and patch cords from the galvanometer plug straight in without screw terminals or clips.
Will the knife-edge damage the bridge wire?
Not with correct use. The plated brass edge is shaped to make a localised contact on manganin or constantan wire; pressing too hard, however, can flatten or kink the wire and alter its local diameter, so students should use light taps.
Is Science Lab Supplies the manufacturer or a trader?
Science Lab Supplies manufactures the jockey in its Saha works near Ambala, India. Orders and quotations are handled by the maker directly, without any trading company in between.
Related Bridge, Potentiometer and Key Apparatus
The items below are used in the same null-method practicals as the jockey: bridges and resistance boxes that form the circuit, galvanometers that show balance, and keys that control the current. They come from the Electrical and Electronics and Lab Meters ranges and can share one quotation.
- Pencil Jockey — bakelite moulded handle, brass plated contact and a locating notch.
- Portable Wheatstone Bridge Apparatus Circuit Board — four-arm bridge with a centre-zero galvanometer.
- Resistance Box Plug Type (Constantan / Manganin Coil) — brass blocks with wound coils in a wooden box.
- Post Office Box Plug Type — measures 0.1 to 1,111,000 ohms, with two spring keys.
- Galvanometer — centre-zero demonstration meter reading −500–0–500 µA.
- Tapping Key Physics Lab — momentary brass spring key rated 24 V DC, 2 A.
- Brass Two Way Plug Key Switch — switches current between two branches, as when comparing two cells.
Browse the full Electrical and Electronics range, the Lab Meters range for galvanometers, or all physics lab equipment.
Last updated: 9 October 2026
