2225

Manuals – Specifications – Links – Pictures

The Tektronix 2225 is a 50 MHz dual-channel analog scope.

It has a single timebase with a ×5/×10/×50 magnifier that allows displaying normal and magnified traces together on the screen, but has no delay feature, only an X position control.

The Y inputs feature a ×10 magnifier that decreases bandwidth to 5 MHz but increases sensitivity to 0.5 mV/Div.

There is a 2225ST model that adds digital storage. Further information needed

A 2205 equipped with option 07 (internal DC inverter) can be powered ≥3 hours from an 1104A battery.

The 2225 was known internally as Euroscope. It was initially developed in Hoddesdon, UK and then produced in Tek's Heerenveen facility.

Key Specifications

Rise time	≤7 ns (≤70 ns with ×10 vertical magnification)
Bandwidth	≥50 MHz (≥5 MHz with ×10 vertical magnification)
Deflection	5 mV/Div to 5 V/Div, 1–2–5; 500 μV/Div with ×10 vertical magnification; variable ≥2.5:1
Input impedance	1 MΩ // 25±2 pF
Maximum Safe Input	400 V (DC + peak AC) or 800 Vp-p AC to ≤10 kHz
Trigger sensitivity	0.3 Div or 40 mV @ 5 MHz, 1 Div or 200 mV @ 5 MHz
Sweep	0.5 s/Div to 50 ns/Div, 1−2−5; ×10 Mag. down to 5 ns/Div; variable ≥2.5 : 1
Z input	5 V causes noticeable modulation (positive decreases intensity), DC to 5 MHz; max. 400 V (DC + peak AC) or 800 Vp-p AC to ≤10 kHz
CRT	154-0907-00 tube, 80 × 100 mm² display, P31 phosphor, 12.6 kV acceleration
Power	95–128 or 185–250 VAC, 48–440 Hz, ≤70 W (80 VA)
Features	X-Y mode (± 3° from DC to 150 kHz) Calibrator (0.5 V ±5% into 1 MΩ Load; 1 kHz ±20%)
Options	(selected) 1R – Rackmount kit 02 − Front Cover and Pouch 07 – Internal DC Inverter (for 11.8–30 VDC supply) 30 – Opt.07 + 1104 battery 18 – P6122 probes instead of standard P6103

Prices

• 1990 catalog: $1,095 ($2,280 in 2021 dollars)
• Wireless World, May 1991: 2225, £400; 2225ST, £550

Links

• Tektronix 2225 Analog Oscilloscope - EEVblog 196
• Tektronix 2225 Oscilloscope Teardown and Calibration - EEVblog 208

Internals

The 2225 power supply uses a 120-1630-00 mains-frequency toroidal transformer to produce a 60 V DC supply, followed by two TL494-driven switching regulators.

The scope uses transistor array ICs like the CA3102, CA3046 and CA3054, but no Tek custom ICs.

Pictures

2225

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2225ST

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Components

Some Parts Used in the 2225

Part	Part Number(s)	Class	Description	Used in
154-0907-00	154-0907-00	CRT	CRT	2225 • 2225ST
TL494		Monolithic integrated circuit	PWM switch-mode controller	2225 • 7250