S-1 Sampling Head 350 ps

Type S-1 Sampling Head

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

S-1 Features:

350 ps Sampling Head
Dc to 1 GHz Equivalent Bandwidth
Displayed Noise <= 2 mV (tangential noise)

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)

Reparatur

(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.

FAILED?

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.

Impressum und Haftungsausschluss