FNIRSI DSO-TC3 vs FNIRSI DSO152

Specs side by side

Specs checked against manufacturer documentation and official Amazon listings. Desk research, not bench testing. How we research.

Key differences

• →Bandwidth: 500kHz on the DSO-TC3 against 200kHz on the DSO152, 2.5 times more. By the 3–5× rule that moves the comfortable ceiling from roughly 40–65kHz to roughly 100–170kHz.
• →Sample rate: 10 MSa/s against 2.5 MSa/s, four times faster, so the DSO-TC3 takes 20 samples per cycle at its bandwidth limit against 12.5 on the DSO152.
• →The DSO-TC3 adds a component tester (transistors, MOSFETs, diodes, capacitance, resistance, inductance) and a 6-waveform signal generator up to 100kHz. Neither function is in our verified data for the DSO152.
• →Both have one input channel, so neither can show two signals side by side.
• →FNIRSI states the DSO-TC3's 2.4-inch screen, built-in rechargeable battery and USB-C charging. Our verified DSO152 data does not state its screen size or power source, so we can't compare those directly.
• →FNIRSI does not state the DSO-TC3's ADC resolution or memory depth, and neither appears in our DSO152 data either.

Spec by spec

These two are far closer than a pocket scope and a bench scope, so the charts use a linear scale. The gaps are real but modest: 2.5 times the bandwidth and 4 times the sample rate. Every number comes from the maker's published specs in our beginner roundup; the last chart is derived from them.

For what bandwidth and sample rate actually mean on screen, see what oscilloscope bandwidth is and what GSa/s means. The same ideas apply at MSa/s, just a thousand times slower.

Which is better for beginners?

For most beginners the DSO-TC3 is the better learning tool, and the reason isn't its extra bandwidth. It is the built-in signal generator. When you first use a scope, the hardest part is often having something sensible to look at. With the DSO-TC3 you can generate a waveform of a known shape and frequency, feed it into the scope input, and practice setting the timebase, the volts per division and the trigger until the trace sits still. Because you know what the answer should be, every mistake in your settings shows up straight away. The DSO152 can teach the same controls, but only if you already have a circuit or a separate generator producing a signal.

The component tester is the second beginner advantage. Sorting out which leg of a transistor is which, checking whether a salvaged capacitor is still within its value, or confirming a diode's direction are everyday jobs when you start building circuits, and the DSO-TC3 covers them in the same box. FNIRSI lists wide ranges, capacitance from 25 pF to 100 mF, resistance from 0.01 Ω to 50 MΩ and inductance from 10 µH to 1,000 mH, but doesn't state the tester's accuracy, so treat it as a sorting and sanity-check tool rather than a precision instrument.

The DSO152 makes more sense when you want the simplest possible scope and nothing else. Its data calls it an extremely affordable entry point, and for a beginner who mostly wants to watch audio signals or a slow PWM pin, its 200kHz is enough. Its review covers that role in more detail: FNIRSI DSO152 review.

Which should you buy?

What each one can and can't measure

A scope's bandwidth is the frequency at which a sine wave is shown about 3 dB low, roughly 70% of its true amplitude. The usual rule of thumb is to pick a scope with 3–5 times the frequency of the signal you want to see, and more for square waves, whose sharp edges contain harmonics well above the fundamental.

FNIRSI DSO152: audio range and slower

At 200kHz, the DSO152 is comfortable up to roughly 40–65kHz. That covers the audio band (up to about 20kHz), the ripple on a linear power supply, slow sensor outputs and low-frequency PWM. A square wave of a few kilohertz will look square; one at 50kHz will already show softened edges.

FNIRSI DSO-TC3: a little further

At 500kHz, the DSO-TC3 is comfortable up to roughly 100–170kHz. That takes in everything the DSO152 can show, plus higher-frequency PWM and ultrasonic signals around 40kHz with more margin. A 100kHz I2C clock sits right at the edge of its comfortable range: you can see that it is toggling, but don't trust its edge shape. Megahertz SPI clocks, most switching regulators and fast logic are beyond both scopes.

The model makes the 3–5× rule visible. At 100 kHz the DSO-TC3's trace reaches the top within about a seventh of each half-cycle and then sits flat, so the waveform still reads as a square wave. The DSO152 spends about a third of each half-cycle climbing, which turns the same signal into something closer to a shark fin. Drop the signal to 20 kHz, inside the DSO152's comfortable range, and each half-cycle stretches to 25 µs; its 1.75 µs edge then takes only 7% of that, and both scopes draw a convincing square wave.

Where to go next

If either pocket scope leaves you wanting a second channel or more bandwidth, the next step is a bench scope. See Rigol DS1054Z vs FNIRSI DSO152, FNIRSI DSO152 vs Hantek DSO2D10, FNIRSI DSO152 vs Siglent SDS1104X-E and FNIRSI 1014D vs FNIRSI DSO-TC3, or start from the oscilloscope buying guide.

Frequently asked questions