Skip to main content


to AZUR Electronics

Test Equipment
Operating Information
For Sale
About Me
Contact Me
Site Map


Microsoft are discontinuing this website service soon!

Please go to my new website




This is the Chassis and CRT for the Spectrum Analyzer.  It comprises the low voltage and high voltage power supplies, and the pulse circuits for the variable persistance and storage display modes of the CRT.  It cost $2,600 in 1980.  The right-hand side of the chassis is for either '8550 series' Spectrum Analyser plug-in units or '1400 series' Oscilloscope plug-in units.  I have the paper and downloaded Manuals.






Front view with Display Section on the left and

space for the 2 plug-in units on the right




Rear view with Aux connectors on right



The Rear Panel has a BNC socket for Z-Axis Input and an Internal/External Z-Axis Switch.

Much more complicated are the 2 special D-type connectors.
AUX A is for connection to a Tracking Generator, either 8443A 100kHz to 110MHz, or 8444A 500kHz to 1,300MHz.  Each of these require a special inter-connecting cable.
AUX B is for connection to a 8445B Automatic Preselector, this also requires special inter-connecting cables.
The special inter-connecting cables are essential, expensive and difficult to find!
GLK Instruments manufacture these cables to order, see
Some repair work was required to get this Display Unit fully operational, for details see Repair HP 141T Display Unit.
Internal connectors for plug-ins
Internal connectors from top to bottom are: J2, J9, J11 & J1.
Connectors J2, J9 & J11 mate with the upper plug-in unit, for the Spectrum Analyser either the 8553B, 8554B, 8555A or 8556A.
Connector J1 mates with the lower plug-in unit, for the Spectrum Analyser 8552B.
The utilisation of the pins for J1 and J2 varies depending on the plug-in used.  For the Oscilloscope the 1400 series plug-ins could also be used.  For the Spectrum Analyser details are provided HP 141T Internal Connections.
Details of the special D-type connectors are provided HP 141T External Connections.
Return to  Spectrum Analysers