Description
Tektronix Type 1L5 Spectrum Analyzer Plug-In Unit 50Hz-1MHz Center Frequency
The Tektronix Type 1L5 is a spectrum analyzer plug-in module designed for use with compatible Tektronix oscilloscope mainframes. It extends the mainframe's capability to display signal spectra, enabling frequency-domain analysis across a center frequency range of 50Hz to 1MHz. The front panel is clearly labeled "TYPE 1L5 SPECTRUM ANALYZER PLUG-IN UNIT" and was manufactured by Tektronix, Inc. in Portland, Oregon, USA.
Specifications & What's Included
- Model: Tektronix Type 1L5
- Part Number: 386-1109-00
- Type: Spectrum Analyzer Plug-In Unit
- Center Frequency Range: 50Hz – 1MHz
- Frequency Counter Dial: Mechanical counter, reads in Hz (set to 1100 Hz in photos)
- Vertical Display: Log (dB/cm) and Linear (RMS V/cm) selectable
- Volts/cm: Variable, fine calibrated attenuator with multiple range positions
- Dispersion Hz/cm: Selectable — includes stepped and manual ranges
- Sweep Mode: Manual and Auto (positions 1, 2, 4, 6, 8 visible on panel)
- Input Rating: 300V Max (1MΩ // 33pF)
- OSC OUT connector: BNC, front panel
- INPUT connector: BNC, front panel
- Sawtooth Output (rear): 100V / 150V selectable switch
- Plug-In Connector: P11 multi-pin edge connector (rear, for mainframe interface)
- Calibration: CAL and VARIABLE frequency controls on front panel
- Manufactured by: Tektronix, Inc., Portland, Oregon, USA
- Includes: Plug-in unit only — no mainframe, cables, or manual included
Applications
The Tektronix Type 1L5 is a vintage spectrum analyzer plug-in from the 1960s, designed for the Tektronix modular oscilloscope mainframe system — the same platform that accepted plug-in vertical and horizontal amplifier units as interchangeable modules. Plug-in spectrum analyzers like the 1L5 allowed lab technicians and engineers to transform a standard Tektronix mainframe into a frequency-domain instrument without purchasing a dedicated standalone spectrum analyzer, which was a significant cost advantage in the era. The 1L5 covers the audio and low-RF frequency range (50Hz to 1MHz), making it well suited for audio frequency analysis, low-frequency signal characterization, filter response evaluation, and oscillator stability checks. Today these units are sought by vintage Tektronix collectors, electronics historians, and engineers maintaining or restoring period-correct lab setups. They also find use in university surplus collections and hobbyist labs with compatible Tektronix mainframes.
This Tektronix Type 1L5 Spectrum Analyzer Plug-In Unit has been pulled from a working environment where it was previously in use. It has been visually inspected and photographed. The front panel shows normal wear consistent with regular lab use — the panel graphics and labeling remain clear and legible, the knobs and controls are intact, and the mechanical counter dial is present. The internal boards and wiring are visible in the photos and appear intact with no obvious damage. The unit has not been powered up or tested at our facility. Please review all photos carefully and contact us with any questions before purchasing.
Warranty Information
Additional Information
Brand: |
Tektronix |
Model: |
Type 1L5 |
MPN: |
386-1109-00 |
SKU: |
37039 |
Type: |
Spectrum Analyzer Plug-In Unit |
Center Frequency Range: |
50Hz – 1MHz |
Frequency Range: |
50Hz to 1MHz |
Vertical Display: |
Log (dB/cm) and Linear (RMS V/cm) |
Sweep Mode: |
Manual and Auto |
Dispersion Hz/cm: |
Variable, selectable |
Input Rating: |
300V Max (1MΩ // 33pF) |
Sawtooth Output: |
100V / 150V selectable |
Plug-In Connector: |
Multi-pin edge connector (P11) |
Country/Region of Manufacture: |
United States |
Form Factor: |
Plug-In Module |
Compatible With: |
Tektronix oscilloscope mainframes (plug-in compatible) |
Seller Notes: |
Plug-in unit only — no mainframe, cables, or manual included. |
Condition Notes: |
This Tektronix Type 1L5 Spectrum Analyzer Plug-In Unit was pulled from a working environment and has been visually inspected. Front panel, knobs, and counter dial appear intact. Not powered or tested at our facility. |
California Prop 65 Warning: |
WARNING: This product can expose you to chemicals including lead and lead compounds, and DEHP (a phthalate), which are known to the State of California to cause cancer and birth defects or other reproductive harm. Go to P65Warnings.ca.gov |