If you already own an oscilloscope and a bench supply, the function generator is the third instrument that turns a corner of the kitchen table into an electronics lab. It hands your circuit a signal you chose deliberately instead of guessing at, which is the difference between measuring a filter and merely watching one. Most of the questions we get in our inbox follow the same shape: I am following a textbook lab course, I have a scope, what should the generator do?
This guide covers ten bench function generators for hobby labs, from a light dual-channel DDS unit to a 40MHz benchtop model with Ethernet on board. We weighed every one against the same questions: is the sine output clean, are the square wave edges honest, can I automate it over SCPI, and will it still be pleasant to live with after a year on the bench. Prices move constantly, so use the check buttons rather than any figure you may remember from elsewhere.
One thing to know before you read a single spec sheet. The headline bandwidth number on almost every unit here is a sine-wave figure. Square, pulse and arbitrary waveforms are usually capped far lower, often in the 10-25MHz range, and the gap is widest on the units with the most impressive marketing. We call this out for each product below. Everything else in this roundup is written on the same basis, and we lean on owner reports rather than brochure adjectives where we can. If your bench also needs power away from a wall socket, our portable solar generator tests cover that side of the setup.
Table of Contents
Top 3 Best Function Generators for Hobby Labs (October 2026)
Koolertron 15MHz DDS
- Dual channel 15MHz sine
- 200MSa/s and 14-bit
- 60 user waveform slots
- Built-in pulse-width counter
Abestop 70MHz Dual-Channel
- Dual channel 70MHz
- 300MSa/s and 14-bit
- 160 built-in waveforms
- SCPI and LabVIEW over USB
Best Function Generators for Hobby Labs at a Glance in 2026
| Product | Specifications | Action |
|---|---|---|
| Siglent SDG2042X 40MHz |
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| Koolertron 15MHz DDS |
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| Abestop 70MHz Dual-Channel |
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 OWON DGE1060 60MHz |
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 Seesii 60MHz DDS |
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 Walfront JDS6600 15MHz |
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 UNI-T UTG932E 30MHz |
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 DOMINTY FY6900 60MHz |
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 Rigol DG1022Z 25MHz |
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 YERTAI ET3320C 20MHz |
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Check Latest Price |
1. Siglent SDG2042X – the benchtop pick for a serious hobby lab
Siglent Technologies SDG2042X Arbitrary Waveform Function-Generators, 40 MHz, Grey
Dual channel 40MHz sine
16-bit vertical resolution
TrueArb and Easy Pulse
USB and LAN
Pros
- Quiet cooling fan in normal use
- Accurate low-noise sine output
- Large sharp touchscreen with button navigation
- Compact benchtop footprint
- North America warranty support
Cons
- EasyWave waveform software is Windows-only and awkward to use
- Manual barely explains TrueArb versus DDS modes
- Quick-start paperwork is thin
The Siglent SDG2042X is the best function generator for hobby labs that have outgrown a pocket DDS box. Two fully independent channels at up to 40MHz sine, 16-bit vertical resolution and both USB and Ethernet make it the one instrument here that can sit at the centre of a real bench rather than at the edge of it.
Owners consistently describe the output as accurate and quiet, and the cooling fan is rarely the complaint we would expect on a chassis this size. The touchscreen is large and sharp, and the fact that it also has physical buttons matters more than it sounds when your fingers are greasy and you are probing a circuit.
The honest weaknesses are all software and documentation. EasyWave, the PC tool for building arbitrary waveforms, runs only on Windows and reviewers describe it as awkward rather than intuitive. The manual spends very little time explaining when to use TrueArb and when plain DDS is the better choice, so expect to experiment.
What you get that cheaper units do not
The built-in high precision frequency counter is genuinely useful. When you are aligning a filter or checking an oscillator that has drifted, having a trustworthy reference on the instrument itself removes a whole class of guesswork. Ethernet is the bigger deal: it is what lets the generator pair with an oscilloscope for automated Bode plotting instead of a manual knob-turning session.
There is one firmware behaviour worth knowing before you plan a pulse-width experiment. The unit will not accept very low duty cycle values directly, so extremely narrow pulses need burst mode workarounds. That is a small inconvenience, but it is exactly the kind of thing that wastes an evening if you hit it cold.
Where it is the wrong choice
If your work is audio, sensors and microcontroller input testing at a few megahertz, the 40MHz sine capability is headroom you will not use, and the learning curve is real. Beginners usually get more out of time on a simpler front panel. Save this one for when you want remote control, dual-channel phase work, or accurate arbitrary waveforms at higher frequencies.
2. Koolertron 15MHz Dual-Channel DDS – the best value pick
Koolertron 15MHz DDS Signal Generator, Dual-Channel
Dual channel 15MHz sine
200MSa/s sampling
14-bit vertical resolution
99 stored parameter sets
Pros
- Stable low-distortion dual-channel output for the money
- 14-bit resolution at 200MSa/s
- 99 state memories plus 60 user waveform slots
- Built-in frequency period and pulse-width measurement
Cons
- Basic panel with no touch interface
- No sync or trigger output for scope sweeps
- Fewer channel and sweep options than benchtop instruments
The Koolertron 15MHz is the recommendation we make most often to someone building a first lab on a budget. It has more owner reviews than anything else in this roundup by a wide margin, and the reason is straightforward: it is a dual-channel 14-bit instrument with real storage and measurement functions, which is far more than the price band usually delivers.
Output quality is the surprise. Reviewers describe stable, low-distortion dual-channel sine, which matters because a generator with a noisy source can hide the very filter response you are trying to measure. At 15MHz sine the unit is honestly limited, but for audio, sensor and microcontroller work that ceiling sits well above what those projects need.
The linear and logarithmic sweep functions run up to 999.9 seconds, which makes slow filter sweeps and speaker response checks practical without any scripting. The 99 parameter memories and 60 user waveform slots at 2048 points each mean you can rebuild a test setup in seconds instead of re-entering a dozen values.
Why hobbyists keep recommending it
The built-in frequency, period and positive or negative pulse width measurement functions are unusual at this level. Being able to confirm a pulse width on the generator itself, then confirm it again on the scope, catches wiring mistakes before they turn into a whole afternoon of debugging.
Students and self-taught builders mention the same strengths consistently: value, a complete waveform set including white noise, and enough storage to keep several experiments saved. It is a basic benchtop instrument rather than a laboratory-grade one, and knowing that is the point.
Where it falls short
There is no touch interface, so every change is a knob or button sequence, and menu navigation is slow enough that you will want to save states rather than explore live. More significantly, there is no sync or trigger output, which makes the sweep functions awkward to pair with a scope that needs an external trigger to hold the display steady.
If your work leans heavily on radio or IF signals, 15MHz sine will feel like a ceiling sooner than you expect. For everything else on a hobby bench, it is hard to argue against.
3. Abestop 70MHz Dual-Channel – the most beginner-friendly dual channel
Dual-Channel Arbitrary Waveform Function Generator, 70MHz, 300MSa/s, 14-Bit
Dual channel 70MHz
300MSa/s sampling
14-bit resolution
160 built-in waveforms
Pros
- Amplitude frequency and offset track the displayed values closely
- Large library of built-in arbitrary waveforms
- Lightweight body and easy-to-learn front panel
- Selectable 50 75 600 ohm and high-Z loads
Cons
- Waveform distorts near the rated maximum
- Amplitude readout is peak-positive not peak-to-peak
- Very light chassis that slides on a hard bench
The Abestop 70MHz dual-channel unit is the one we suggest when someone asks which function generator will not discourage them. The front panel is legible, the 3.6-inch LCD is clear, and per-channel waveform buttons let you change one output while the other keeps running, which is a small thing that makes dual-channel work far less intimidating.
Under the hood it is a serious specification: 70MHz across two independent channels at 300MSa/s and 14-bit resolution, with 160 built-in arbitrary waveforms on top of the five basics. Reviewers who have compared it against laboratory references report that amplitude, frequency and DC offset match the displayed values closely on a scope.
USB PC control with SCPI and LabVIEW support means this unit can start a life as a beginner box and grow into an automated bench later. The selectable load impedance setting, with 50, 75, 600 ohm and high-Z options, is unusual and useful when you are driving audio and line-level circuits rather than 50 ohm RF.
Best things to check before you rely on it
Two behaviours are worth internalising on day one. The waveform starts to distort as you approach the rated maximum frequency, so treat the 70MHz figure as a headline rather than a working point. And the amplitude readout is peak-positive, not peak-to-peak, which catches out beginners who assume otherwise and then wonder why their measured signal is half what the display claims.
The printed manual is very brief and the full version has to be fetched from the manufacturer’s site. Budget an hour for that read. It pays back immediately because the modulation menu structure is not self-evident.
Where it is the wrong choice
The body is very light, and owners report that it slides across a hard bench surface while you are adjusting a probe. That is a nuisance rather than a fault. The higher review count still matters if you want a long ownership record, and there is little of that documented here yet.
4. OWON DGE1060 – the compact single-channel pick for audio work
OWON Waveform Generator, 60MHz Bandwidth,300MSa/s Sampling Rate, 14 bits Vertical Resolution, 8K Waveform Length, 5 Basic Waveforms, 160 built-in Arbitrary Waveforms, with 3.6IN LCD Display DGE1060
60MHz sine bandwidth
300MSa/s real-time sampling
14-bit resolution
160 built-in arbitrary waveforms
Pros
- Frequency accuracy measured within a few ppm against a reference
- Large repertoire of built-in arbitrary waveforms
- AM FM and tone burst functions useful for radio work
- Thin portable body with a 3.6-inch TFT
Cons
- Radiated VHF and UHF noise from the electronics
- Conducted noise from the supplied power adapter
- No sync output and only a single channel
The OWON DGE1060 is the pick when bench space matters more than channel count. It is a single-channel instrument with a thin portable body, an 8K record depth and 16 stored digital arbitrary waveforms, and it delivers the frequency accuracy hobby work actually depends on.
Accuracy is where the reviews single it out. Owners who checked output against a WWV reference report agreement within a few ppm, which is the kind of margin that makes a frequency-response sweep across a filter trustworthy rather than merely repeatable. The display also mirrors the waveform as it appears on a scope, a small touch that reduces the learning curve.
For radio and audio work the AM, FM and tone burst functions are directly useful, and 160 built-in arbitrary waveforms cover most experiments without touching a PC.
The square and triangle bandwidth is far below the 60MHz headline sine figure, so plan your digital edge experiments around the lower number. Very low amplitude settings, around 20mVpp, are also reported to be unstable, which matters if you work with small signals.
When a single channel is enough
For alignment and tone work this is the right trade. If you only ever drive one input at a time, a second channel adds nothing, and the thin body leaves you space for a second instrument on the same shelf. You also gain the 160 built-in arbitrary shapes, which buy back most of what a dual channel would have given you.
Check this before you put it next to an RF receiver
Owners report two noise problems that no spec sheet mentions. Radiated VHF and UHF noise from the electronics can swamp a nearby receiver, and conducted noise from the supplied power adapter shows up on unshielded connections. If your hobby includes listening to shortwave or working near a sensitive radio, that is the deciding factor.
There is also no sync or trigger output, so sweep-based work needs a different approach, and with a single channel you cannot do phase or differential testing at all. Budget your cables separately, since the package includes the user manual rather than leads.
5. Seesii 60MHz DDS – the dual-channel pick for radio and RF
Professional Upgraded DDS Signal Generator Counter, Seesii 60MHz LCD Display High Precision 200MSa/s Dual-Channel Arbitray Waveform Function Generator Frequency Meter
Dual channel 60MHz sine
200MSa/s sampling
Per-channel duty cycle control
Linear and logarithmic sweep
Pros
- Dual channels with independent parameter control
- Clean fast square wave transitions
- Useful frequency counter and sweep functions
- Bundled software for custom waveforms
Cons
- Overshoot on square wave leading and trailing edges
- Audible output noise and no sweep trigger output
- Signal pulls down noticeably when driving a load
The Seesii 60MHz JDS6600 is a popular way to get two independent channels with real RF headroom at a hobby price. Sixty megahertz of sine, 200MSa/s sampling, per-channel duty cycle adjustment at 0.1% precision and both linear and logarithmic sweep to 999.9 seconds.
Reviewers rate the square wave transitions as fast and clean, which is exactly what you want when driving a mixer or a comparator stage. The waveform library covers the usual set plus noise, and bundled software handles custom waveforms and frequency combinations without a separate purchase.
The linear and logarithmic sweep plus a built-in counter make it a natural fit for receiver alignment work, where you want to walk a tone across a band and watch the response rather than stepping through frequencies by hand.
Owners’ reliability notes
This is not a laboratory-grade instrument, and the most common complaint is overshoot on the leading and trailing edges of the square wave. If your circuit is sensitive to edge overshoot, add a series resistor at the output and re-measure before drawing conclusions about your circuit.
Output noise is audible to some owners, there is no start-sweep or trigger output for scope synchronisation, and the chassis is light with hard plastic feet that slide on a hard bench. Signal also pulls down noticeably when driving a load, so treat the amplitude readout as a reference rather than a guarantee.
When a quieter unit is worth it
Choose something with a lower noise floor when you are working with low-amplitude signals, driving a high-impedance front end, or measuring audio distortion directly. None of those apply to most hobby projects, but all of them turn audible output noise into a measurement error rather than an annoyance.
6. Walfront JDS6600 15MHz – the pick for scripted automation
Walfront JDS6600 DDS Generator Counter 15MHz 60MHz High Exactness Dua Channel Arbitrary Waveform Function Generator Frequency Meter 266MSa/s (15Mhz)
Dual channel DDS
266MSa/s sampling
14-bit resolution
Phase control to 0.1 degrees
Pros
- Wide built-in waveform library for the class
- Phase and offset controls precise for two-channel work
- PC software control with a published communication protocol
- Short-circuit output protection
Cons
- A small number reported dead on arrival
- Reports of early degradation within a few months
- Variant bandwidth descriptions can be confusing
The Walfront JDS6600 earns its place for a specific reason: standard PC software control with an open communication protocol for secondary development. If you want to drive your generator from a script to run a sequence of measurements, having a documented protocol rather than an undocumented serial stream is genuinely valuable.
The waveform library is unusually wide for the class, including CMOS, half wave, staircase and exponential rise or fall forms alongside the standard set and 60 arbitrary waveforms. Owners mention using it for condenser microphone calibration, which is a demanding accuracy task for this price bracket.
What the phase and offset controls unlock
Two-channel phase difference can be adjusted to 0.1 degrees and bias or offset runs from -9.99V to +9.99V, so quadrature and offset-heavy experiments are within reach. Output short-circuit protection is rated at 60 seconds under load short, which is reassuring on a bench where probes get crossed.
What to weigh before buying
The review base here is small, and within it there are outright failure reports: some instruments never powered on, and others reportedly degraded within a few months. That pattern suggests inconsistent quality control rather than a systemic design fault, but it is the kind of thing to weigh against a longer record from a larger brand.
Be careful about which variant you actually receive. This listing covers sine up to 60MHz but square only to 15MHz, and the listing descriptions can be confusing relative to the variant supplied. Confirm the numbers before you commit.
7. UNI-T UTG932E – the pick that arrives with a complete accessory set
UNI T UTG932E Function Generator Arbitrary Waveform Signal Generator
Dual channel to 30MHz
200MSa/s and 14-bit resolution
Ch1 and Ch2 combining
Six modulation types
Pros
- Channel combining enables differential and comparator-style tests
- 24 groups of non-volatile arbitrary waveform storage
- Complete bundle with BNC leads and alligator clips
- 6-digit counter with a TTL level output
Cons
- Switching-supply noise disturbs sensitive measurements
- Reported glitching when changing frequency or phase
- Lowest average rating among these instruments
The UNI-T UTG932E is unusual in this roundup for including everything you need on day one: a power adapter, USB cable, BNC cable, a second BNC cable with alligator clips, a paper manual and an eManual. On a first bench, that bundle saves you the accessory shopping step entirely.
The feature list is long for the tier. Two channels with Ch1-Ch2 combining capability, sine, square, pulse, ramp, noise, DC and arbitrary output from 1Hz to 30MHz at 200MSa/s and 14-bit resolution, six modulation types including AM, FM, PM, FSK, Line and Log, plus 24 groups of non-volatile arbitrary waveform storage.
Channel combining is the underrated part. Adding the two channels with inversion gives you a differential signal source, which turns the instrument into something close to a comparator or small-signal injection tool for amplifier work.
Ham radio alignment, pro audio checks and turntable work are all tasks where one channel at a known frequency is enough and a TTL level output saves an adapter. The 6-digit counter is accurate enough to confirm what you set, which is the main thing you need while trimming.
Best used for bench alignment work
Set the load and amplitude before you connect to a live circuit, then confirm the output on a scope at the point of measurement rather than at the generator end. Long cable runs into audio and line-level stages are where switching-supply noise on this class of instrument shows up first, so a quick look before you trust a reading saves a long debugging session.
Where owners push back
This instrument carries the lowest average rating in the group at 4.1, and the complaints are consistent rather than isolated. Switching-supply noise appears on the output and disturbs sensitive measurements, and owners report glitching when changing frequency, amplitude or phase, which is disruptive during a live sweep.
Owners also note that the documented application claims run ahead of what the instrument delivers in practice. The accessory bundle is genuinely better than most rivals; the signal path is the compromise. If your measurements are quiet and low amplitude, buy the leads separately and buy a cleaner generator instead.
8. DOMINTY FY6900 60MHz – the pick for classroom and shared bench sets
DOMINTY Function Generator AC100-240V FY6900 60MHz Double Channel DDS Function Arbitrary Waveform Signal Generator Frequency Meter 250MSa/s Sine Square/Triangle/Pulse/Sawtooth Wave/Staircase Wave
Dual channel 60MHz sine
250MSa/s sampling
Built-in frequency meter
AC 100-240V input
Pros
- Strong value for a first bench generator
- Low output noise because the driver output is attenuated
- AC ground and BNC shells measuring near 0 ohms
- One-year warranty
Cons
- Tiny hard-to-read display and a small encoder
- Waveform restarts when controls turn quickly
- Flimsy case and no sweep trigger output
The DOMINTY FY6900 60MHz is the instrument we point students at when a lab needs several identical benches. Students and hobbyists recommend it widely as a capable first generator, and 60MHz of sine at 250MSa/s is enough headroom for most course work.
The waveform set covers sine, square, triangle, pulse, sawtooth and staircase, which is everything a typical introductory lab touches. A built-in frequency meter removes one more box from the bench, and AC 100-240V input makes it usable in more regions without a converter.
One detail deserves attention because it has caused real arguments in beginner labs. Owners report that AC ground and BNC shells measure near 0 ohms on newer units, which resolves the floating-ground problem that has caught out a lot of inexpensive generators. If yours measures otherwise, check before you tie grounds together across instruments.
Output noise is low because the driver output is attenuated rather than the input, and a one-year warranty is included.
What to check on arrival
Run the frequency meter against a known source before you rely on it, and confirm the grounds measure near zero ohms between the BNC shell and the AC earth terminal. Both checks take a minute with a multimeter and settle most early doubts before you build anything around the unit.
Best for teaching, less good for finesse
The display is small and hard to read, and the single rotary encoder is uncomfortable for precise adjustment. The most disruptive behaviour is that the output glitches and restarts the waveform when controls are turned quickly, which is exactly what a student does while exploring.
For a shared classroom bench those trade-offs are acceptable, because throughput matters more than polish. For solo work where you will be staring at the display for hours, pick something with a larger screen.
9. Rigol DG1022Z – the pick for sweep and harmonic experiments
Rigol DG1022Z Signal Generator, 25MHz Function Arbitrary Waveform Generator
Dual channel 25MHz
200MSa/s and 14-bit resolution
Harmonic generation and sweep
USB Host USB Device and LAN
Pros
- Clean accurate dual-channel output in a small footprint
- 160 built-in waveforms plus custom arbitrary output
- Broad modulation sweep burst and harmonic support
- Simple easy-to-learn operation
Cons
- Cooling fan noise is noticeable in a quiet room
- Only seven reviews so long-term reliability is not documented
- 25MHz bandwidth is modest next to the wider options here
The Rigol DG1022Z is the pick when harmonic generation is on your list. It is one of the few instruments here that can add a harmonic series to the output directly, which is how you check whether a circuit under test introduces distortion rather than merely tolerates it.
Two channels at up to 25MHz sine, 200MSa/s and 14-bit resolution, with sine, square, ramp, pulse, noise and harmonic waveforms plus 160 built-in shapes and custom arbitrary output. Modulation covers AM, FM, PM, FSK, ASK and PWM, alongside sweep and burst.
Connectivity is the other reason to like it. USB Host, USB Device and LAN interfaces mean it can be scripted, chained with other instruments, or used as a signal source in a bench automation setup. Every one of the current reviews rates it five stars, and owners describe the output as clean and accurate, the operation as simple to learn, and the SiFi II signal fidelity as doing its job quietly.
Best for distortion and filter work
Harmonic generation is what sets this apart. You can add a second and third harmonic to the output and watch how a stage under test responds, which is a direct way to see intermodulation and clipping rather than inferring it. For audio-range analog work that is worth more than raw bandwidth.
Honest limitations
Cooling fan noise is noticeable in a quiet room, which is the only recurring remark in the reviews. More significant is the record itself: with just seven reviews, long-term reliability is not well documented, and that is worth knowing before you build an automated setup around it.
At 25MHz it sits in the middle of this group rather than at either end, so there are faster units for RF work and slower ones that cost less. For harmonic and distortion experiments on audio and low-frequency analog circuits, though, the extra reach of the bigger instruments does nothing for you.
10. YERTAI ET3320C – the budget pick when two channels matter most
YERTAI ET3320C Signal Function Generator, 20MHz DDS Arbitrary Waveform Frequency Counter Machine with USB Communication,Dual Channels
Dual channel 20MHz DDS
200MSa/s sampling
13-bit vertical resolution
100MHz frequency counter
Pros
- Entry-level cost while still offering two channels and a 20MHz range
- About 600g so easy to carry between benches
- Colour TFT with a clear graphic interface
- 50 sets of internally stored edited waveforms
Cons
- 13-bit resolution is the lowest in this group
- Small selection of arbitrary waveforms
- Waveform editing software is not bundled
The YERTAI ET3320C is the most affordable way into this list and it is not a token entry. Twenty megahertz across two channels at 200MSa/s, a 2.4-inch colour TFT, and a light body of about 600g, which makes it easy to carry to a friend’s bench or a repair table away from home.
The features are better than the price suggests. Fifty sets of internally stored edited waveforms, ASK, FSK and PSK modulation, internal and external triggering, USB device communication, and a 100MHz high precision frequency counter with a 32-bit counter. Buyers consistently find it easy to use and surprisingly capable for the money.
Where the compromises are
Thirteen-bit vertical resolution is the lowest here, and you will see it as slightly noisier and less faithful output than a 14-bit instrument at small amplitudes. The arbitrary waveform library of 32 shapes is small next to the 150 and 160-waveform rivals, so plan to build your own complex shapes.
One owner reported an out-of-the-box failure showing only the negative half of the signal, and the waveform editing software has to be obtained from the manufacturer rather than bundled. With a review base of nine, there is not enough ownership history here to put much weight on long-term reliability.
Who should step up instead
Skip this one if your work needs more than 20MHz of sine, if 13-bit resolution will show on the measurement, or if you want a long documented ownership record before committing. In each of those cases the extra spend buys something real rather than a nicer badge, and on a bench that gets used every week the difference shows up quickly.
How Much Bandwidth Do You Actually Need?
Most hobbyists buy more bandwidth than they use. Audio work, including tone generation, amplifier response checks and crossover testing, is comfortable around 100kHz. Sensor and microcontroller input testing, including Arduino, ESP32, STM32 and Raspberry Pi work, sits comfortably under 1-5MHz. Analog and filter work generally wants a few megahertz of headroom above your highest frequency of interest.
Forty to seventy megahertz only becomes necessary for IF and RF work, very fast digital edges, or high-frequency clock signals. If that is not on your project list, a 15MHz dual-channel instrument answers almost every question a beginner has.
The architecture question comes up constantly in beginner discussions. Analog generators are simple, warm up well and produce a genuinely analogue output, but they drift and offer few waveforms. Direct digital synthesis, or DDS, computes each sample from a phase accumulator and a lookup table, which is why sample rate and bit depth drive quality in this list. Arbitrary waveform generators, or AWGs, add user-defined shapes on top of the standard set, which only matters when your test signal is not a standard shape.
Our own hobby-grade gear roundups follow the same rule of matching the tool to the task rather than to the spec sheet, and the same logic applies here.
Setting Up Your Bench: Termination, Grounding and Probe Compensation
Output impedance is the first thing that surprises beginners. Most generators specify 50 ohm source impedance, while most hobby oscilloscopes have a 1 MOhm input. Connect those two and the amplitude you set is roughly double what the scope displays, which looks like a generator fault and is not one. Either terminate the output in 50 ohm or work at high impedance and accept the reading you see.
Grounding is the second surprise, and it is more dangerous. The BNC shell is bonded to mains earth through the power supply, and two instruments with earth-referenced grounds will share a current path. Connect two bench instruments to different mains sockets on different circuits and you can create a ground loop that damages a scope input. A cheap isolation transformer or a ground-loop eliminator solves this properly.
Match your generator bandwidth to your scope bandwidth rather than exceeding it. Driving a 60MHz sine into a 20MHz scope produces a display that is wrong in a way that is hard to see, and beginners regularly measure their scope rather than their circuit.
Probe compensation belongs here too. Use the generator square wave output at roughly 1kHz to drive the probe compensation output on your scope, adjust the compensation capacitor with a small screwdriver, and confirm the square wave has flat tops with no overshoot or rounding. It takes two minutes and it fixes the most common source of probe measurement error.
Finally, budget for cables. Most budget instruments ship with the mains lead, the USB cable and a manual, but not with quality 50 ohm BNC leads or a BNC-to-minigrabber set. Adding good cables is inexpensive compared with debugging a bad connection, and it is the difference between a clean trace and a mystery. If you also need bench power away from a wall, our camping generator tests cover quiet options for that.
Frequently Asked Questions
What are the limitations of using a function generator?
The main limits are waveform-dependent bandwidth and output current. The headline MHz rating applies to sine waves only, so square, pulse and arbitrary output is usually capped much lower. Most instruments also cannot supply meaningful current, so driving a load directly will pull the signal down. They do not produce realistic noise, ripple or mains hum without extra circuitry.
Where can I find a cheap function generator?
Start with the budget tier in this roundup: a dual-channel 20MHz DDS unit covers beginner projects and sits at the low end of what we tested. Add a set of quality 50 ohm BNC leads and a BNC-to-minigrabber set, because most budget units ship without them, and that accessory cost matters more than the difference between two budget models.
What is the best frequency generator on the market?
For a hobby lab, the Siglent SDG2042X is the strongest all-round choice, with dual 40MHz channels, 16-bit resolution, Ethernet and USB, and the highest rating among the instruments here with a substantial owner record. If your work stays under 15MHz and your budget is tight, a dual-channel 14-bit DDS unit is genuinely good enough.
What is the difference between a function generator and an arbitrary waveform generator?
A function generator produces standard shapes such as sine, square, triangle and pulse. An arbitrary waveform generator adds user-defined shapes loaded into memory, which lets you reproduce a captured signal or a complex custom pattern. Most instruments in this roundup are both, with an arbitrary section on top of the standard waveforms.
Do function generators come with test leads?
It varies. Bench-oriented instruments such as the UNI-T UTG932E include BNC cables and a lead set with alligator clips. Entry-level DDS units often ship with the mains lead, a USB cable and a manual only. Check the box contents listing before you order, and plan to buy a 50 ohm BNC cable set regardless.
Final Verdict by Budget and Use Case
If you want one answer, buy the Siglent SDG2042X. It is the only instrument in this roundup that combines dual 40MHz channels, 16-bit resolution, Ethernet for automated Bode plotting, and the strongest owner record of the premium tier, and it stays comfortable on a small bench at 1.6 pounds.
If the budget is tighter, the Koolertron 15MHz dual-channel unit answers almost every beginner question for far less, with 99 stored states and built-in pulse-width measurement as bonuses. For dual-channel work under 70MHz on a smaller budget, the Abestop 70MHz dual-channel unit offers the most approachable panel and the largest waveform library. Push radio and RF work and go to the Seesii 60MHz. For harmonic and distortion experiments, the Rigol DG1022Z is the only one here with harmonic generation built in.
Whichever you choose, match its bandwidth to your projects, check the termination and grounding before you trust a single reading, and buy proper BNC leads. That last step costs less than any generator in this guide and improves every measurement you will ever take.