TinySA is an amazing gizmo! I have already posted some video link on TinySA and here is some mode material on it. RF testing is getting quite popular these days, with many devices featuring wireless capabilities. However, RF test devices are quite expensive, or at least have been, as on few recent years many affordable RF test instruments have became available.
TINYSA IS A $49 SPECTRUM ANALYZER that I got from Banggood. The tinySA is a small spectrum analyzer, primarily intended for 0.1MHz to 350MHz input but can be used with higher frequencies up to 900 MHz.
The tinySA is a small spectrum analyzer having dual inputs. One of the input enables working frequencies over the MF/HF/VHF bands of 100KHz to 350MHz and the second input enables a lower quality frequency measurements over the UHF band of 240MHz to 960MHz. Really neat what could be done with the cheap SI4432 modules, the variety of cheap MCU’s,
The tinySA is aimed at radio amateurs, students, and electronic enthusiasts. The primary use is to measure the power of the spectrum of known and unknown signals. Spectrum analyzers are widely used to measure the frequency response, noise and distortion characteristics of all kinds of radio-frequency (RF) circuitry.
Spectrum Analyzer with two inputs, high quality MF/HF/VHF input for 0.1MHZ-350MHz, lesser quality UHF input for 240MHz-960MHz.
Switchable resolution bandpass filters for both ranges between 2.6kHz and 640kHz
Color display showing 290 scan points covering up to the full low or high frequency range.
Input Step attenuator from 0dB to 31dB for the MF/HF/VHF input.
When not used as Spectrum Analyzer it can be used as Signal Generator, MF/HF/VHF sinus output between 0.1MHZ-350MHz, UHF square wave output between 240MHz-960MHz.
A built-in calibration signal generator that is used for automatic self test and low input calibration.
Connected to a PC via USB it becomes a PC controlled Spectrum Analyzer
Rechargeable battery allowing a minimum of at least 2 hours portable use
Due to the low cost and very small form factor there are certain relevant limitations.
The product comes in quite nice looking box that contains pretty much everything needed to get started to use the device:
The device is ready to be tested when you take the tinySA and antenna from the box.
Testing to see the radio signals around me.
Device information from the back of the tinySA.
The tinySA also features a 2.8” color display screen showing 290 scan points covering up to the full low or high-frequency range. It Input Step attenuator can be set from 0dB to 31dB for the MF/HF/VHF input, but the UHF input cannot exceed 10dBm. TinySA has a switchable resolution bandpass filters between 2.6kHz and 640kHz. The tinySA can be connected to a PC via USB it becomes a PC controlled Spectrum Analyzer. You can view the tinySA output on your PC if you use tinySA-saver (multi-platform) or the tinySA PC software (only runs on Windows). . Rechargeable battery allows a minimum of at least 2 hours portable use.
The tinySA also features a built-in calibration signal generator that is used for automatic self-test and low input calibration. When not used as Spectrum Analyzer it can be used as Signal Generator, MF/HF/VHF sinus output between 0.1MHZ-350MHz, UHF square wave output between 240MHz-960MHz. Signal Generator offers MF/HF/VHF sinus output between 0.1MHZ-350MHz, it can output a sinusoid with harmonics lower than -40dB of fundamental at an output point that is pickable in 1 dB steps between -76dBm and -6dBm. It also features an optional AM and FM module or a moderate brush over the selective frequency range (UHF square wave output between 240MHz-960MHz).
There are many features in tinySA, but there are also some limitations. Due to the low cost and very small form factor there are certain relevant limitations. As the internal components of the tinySA where selected with a careful balance between performance and cost there are certain limitations that experienced users of much more expensive spectrum analyzers must be aware of:
The internal phase noise sets a clear lower limit for phase noise measurements.
The minimum resolution bandwidth of 2.4kHz makes it impossible to see more spectral detail
The high input (240MHz to 960MHz) has very limited image suppression and only one level optional built in attenuator which makes it difficult to interpret complex signals.
The high input optional input attenuator is frequency dependent and varies between 25dB and 40dB
At lower resolution bandwidths (below 30kHz) the measurement time per point starts to increase due to the resolution filter implementation. Careful use of the FAST sweeping mode may reduce this time increase
The performance limitations of the shielding and the filters may lead to certain images and spurs being visible but certain functions like spur suppression and switching to below IF may help detect and/or reduce these spurs and images
Below 0.1MHz the sensitivity starts to reduce.
Below 1MHz it is recommended to disable the AGC and possibly enable the LNA to get best measurement quality
When using the supplied telescopic antenna or a low RBW one should be aware of the radiation from the tinySA MCU on 48MHz and its harmonics
There is currently no clone of tinySA. All are genuine and manufactured by Huyen.
Excellent work, it’s amazing that so much functionality can be brought into such a small unit and at such a low cost. This will be a very useful piece of test equipment.
TinySA works as pretty nice spectrum analyzer. Like any spectrum analyzer, it is possible – easy, even – to overload the front end and generate harmonics and spurs. If you are aware of the tinySA’s limitations, it works surprisingly well. If you can keep signals below -35 dBm and most of spurs disappear. The issue in keeping signal levels low is that -35 dBm is pretty low so thiscuts way into the usable dynamic range. The TinySA doesn’t have a front end tracking filter, so strong out of band signals can cause problems. The attenuator helps. Nobody expects a low NF for a spectrum analyzer, so that’s not a big deal.
How tinySA compares to NanoVNA? They are different things designed for different tasks although they have quite similar looking form factors. While there are similarities, the tinySA is NOT NanoVNA hardware. The NanoVNA is a VNA, for measuring S-parameters for reflection, transmission, and impedance properties of a system. You might use it to measure SWR, filter frequency response, transmission line velocity factor, input impedance, etc. A spectrum analyzer measures the frequency content of rf signals into its port. It’s good to testing things like harmonic suppression, spectral purity, intermodulation, etc. The hardware on tinySA is in many ways different from NanoVNA. What differentiates TinySA from Nano VNA is the TinySA includes switchable input attenuators. To get the best measurement performance, it is important to pre-scale the input signal to the level where the detector has its best trade-off of linearity and sensitivity. There are also other Spectrum Analyzer factors such as resolution bandwidth, IF bandwidth and type of detector (peak/average/log/minimum) that are not as important considerations to a vector network analyzer that is generating its own controlled stimulus signal. IMSAI Guy did a video teardown so you can see that it is not the same as the NanoVNA design at all. TinySA – Spectrum analyzer with tracking generator (Reincarnation of nanoVNA) is develeperd by hugen79 (of NanoVNA-H, -H4, v2.2N) and Erik Kaashoek. TinySA uses different analog hardware for the Spectrum Analyzer and Signal Generator functions. Same screen and case. Some of the NanoVNA code has been used for the screen and user interface. There was an attempt to write different firmware to turn the NanoVNA into a Spectrum Analyzer but the analog hardware is just not suitable.
If you are doing RF experimenting it might be a good idea to have both gadgets. By having both tinySA and the NanoVNA (which can also work as a signal generator) you’ve basically got $100-120 to get the RF equivalent of a DMM.
“How does it compare to the RTL-SDR?” Apples to oranges. The tinySA is a spectrum analyzer. The RTL-SDR is a receiver. tinySA offers significantly better bandwidth and a lower noise floor ~100dB for the frequency range spec. Works well below -30dB so consider using with attenuation or signals of interest. tinySA offers small and stand alone operation. RTL-SDR needs to have a computer and has ~-70db noise floor, has more limited dynamic range and slow frequency scanning. On the other hand, the RTL-SDR gives you real time I and Q samples at 2 megasample/sec or more over USB, making it a very flexible receiver when used with a computer. You can build almost arbitrarily complex virtual receivers the GNU Radio software and an RTL-SDR. One of the bigger problems with the RTL-SDR is that there are no pre-selector filters, making it susceptible to overload and intermodulation of out-of-band signals with the signal you want. The RTL-SDR is OK but not great for 1.0 MHz – 30 MHz.
For more information:
The tinySA firmware code is available on github because parts of it are based on open source NanoVNA (and other) code, it had to be open source: https://github.com/erikkaashoek/tinySA
How to Test EMP Proof Container with tinySA. Let’s Test The Tactical Trash CanErik Kaashoek Youtube with new tinySA videos