Type S-1 Sampling Head

S-1 Sampling Head in 7S11 Plug-In together with a 7T11A Timebase

S-1 Features:

The Tektronix S-1 Sampling Head is a <= 350 ps risetime unit with a 50 Ohm input impedance. The S-1 can be plugged into the sampling unit or attached by a sampling head extender for remote use.

A trigger pickoff within the S-1 provides a trigger signal output from the plug-in unit. Signal range - Variable dc offset allows signals between +1V and -1V limits to be displayed at 2mV/div.

Save Overload maximal +/-5V. Fits in 7S11 and 7S12 and classic 5xx  scope series Plug-In's, 3S2.

The S-1 Sampling Head is a low noise unit and a clean step respone with less aberrations.

(from Instruction Manual)


(10. Januar 2010)

Ein 7000er Mainframe (4 Einschub Gerät) machte beim Einschalten zusammen mit dem Sampling Head einfach nur noch click-click-click.....
Das ist ein Anzeichen, dass einer der Schutzmechanismen in der Power Supply angesprochen hat, sehr wahrscheinlich der Kurzschluss Schutz gegen einen zu hohen Laststrom.

The Sampling Head had a short circuit, in a Four Plug-In Mainframe the power supply short circuit protection was active, the mainframe was in the clicking mode.

Diese Einschübe sind mechanisch gut zugänglich aufgebaut, alle Leiterplatten können als Ganzes rausgezogen werden.

A clever mechanical design, it's easy to pull-out the PCB modul, removeable in less than one minute.

Die Leiterplatten sitzen alle aufeinander gesteckt und sind einfachst zu entfernen.

Error within this PCB, the preamp circuit board.

The +15V Supply had a fault, a short circuit

C43, a 3.3µF capacitor had a short circuit, it seems to be a tantalum.

This capacitor series looks like a resistor, note the labeled text 3R3µF

A complete short circuit, capacitor had only 4 milliohms. Measurement cable resistance canceled out with the DMM "MATH" function.

This was a classic fault, old tantalum series sometimes tend to go in a short circuit. An easy to find fault in this Sampling Head, there are not many power supply by-passing capacitors built-in and all PCB's can be separated from each other.

Replaced by a modern type X7R ceramic capacitor of a similar capacitance.

Seaching for the fault and repairing the instrument took less than one hour.

S-1 Step Response coming from a 284 pulse generator, connected with a 30cm airline.

50mV = 20%

Vertical Expanded
20mV = 8%

Measured Aberrations approximately -4% in the first 2ns.

Specified are -3% in the first 2ns.


Received Sampling Head is in an unknown calibration status, DUT need a detailed performance check and calibration.

Source 284 with a 30cm airline

Source 284 with a 30cm airline

Measured S-4 Risetime approximately 270 ps.

Crisp and sharp trace, less noise.

www.amplifier.cd        Tektronix Gallery        Index


Impressum und Haftungsausschluss