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I understand there needs to be a frequency limit somewhere, but just wondering why 960mHz.? I would love to see it go to maybe 1.5gHz.
Keith

Me too.
Not now

My guess would be limitations of the spectral purity of the local oscillator. (I haven't seen the hardware design.)

The two ranges suggest that it works similarly to the NanoVNA: a signal source is being used to generate frequencies up to 320 MHz, and the third harmonic of that source is used for the higher frequency range. Enabling an even higher range to 1.5 GHz would require using the fifth harmonic of the LO or switching to a different LO design.

As those of you have used the original NanoVNA (probably just about everybody here) know, the dynamic range is severely limited on the highest range, the one that extends coverage to 1.5 GHz. That's because you're going way beyond what the Si5351A is intended to do. It is still useful for many applications of a VNA, but a dynamic range of 40dB is too low for most of the things you use a spectrum analyzer for. It's not enough, for example, to use it to detect non-compliance with FCC spectral purity requirements for transmitters. TinySA will not be a lab grade instrument and as such is probably not adequate for full compliance testing; you'll still need verification by a better equipped lab for that. But it can serve as a way of finding non-compliant designs.

The tinySA does a double conversion with a first high IF at 433MHz for its low input IF? range (till 350MHz). Performance is more then sufficient for measuring spectral purity of HF transmitters. The high range, till 960MHz, is not a harmonic mode like nanoVNA but uses a separate direct conversion IQ mixer to a IF of 700kHz. Hence the very different performance.
An experimental tinySA using harmonic modes and SW mirror elimination was able to reach above 4GHz with reduced sensitivity but this is not ready for wide use.
More technical details in the wiki?

Having full control over the internals of the tinySA allowed some experiments at higher input frequencies using the mixer and BPF in a creative way. This of course required the elimination of the low input low pass filter.
Here you have a short set of screen captures that demonstrates a slightly modified tinySA is able to measure higher input frequencies with some limitations as at least the power level is not reliable. Once solved, this has promise to? become a "tinySA special", or an opportunity for hackers
The input is an ADF4351 set to 2.3GHz, 2.4GHz, 2.5GHz and 2.6GHz. TinySa settings are identical in all 4 measurements.

And some practical?examples
First DECT traffic just below 1.9GHz and second WiFi traffic around 2.45GHz. Red line is current signal, yellow line is power envellop

Dear Eric,

i am new to this forum, but have ordered TinySA.?

I own a shack full of HP 141 and other boat anchors, which have hardly ever been used. I am very interested in what you have done to get a TinySA board working up to 3ghz.

i am sure there would be a market for a 300mhz-3ghz Analyser so that this and the TinySA would cover the whole range from zero to 3ghz. I could then get rid of all those boat anchors. I am having to downsize sixty years (!) of collected radio equipment and electronics stuff as I am never going to use/repair most of it. (I also have a large quantity of vintage computer stuff I want to actually get working prior to possible donation to a computer museum).

Stephen Laurence, G7PSZ

As explained in previous posts the current tinySA design with some small HW and SW modifications can go up to 3GHz (using harmonic modes) with a HUGE disclaimer.
It can be VERY difficult to interpret the measurements and we expect MANY customers complaining so it is NOT a feasible product.
I have studied how to do a more robust design up to 2GHz or 4GHz and if you are willing to drop the bottom 300MHz (0-300MHz) it is feasible for an acceptable cost.
But for now not on the priority list.

Thankyou.

I have played with my HP141 boat anchors using the highest frequency plug-in in the past and adjusted the centre freqency knob to see if signals go up or down in the display (to determine if it is a genuine signal or spurious spike due to harmonics etc). This is easier to do with a knob on the old gear rather than changing frequency via the menu (sorry if I am telling readers how to suck eggs).

i am sure your possible robust design specifically for the high frequencies (dropping 0-300mhz) would make a complementary unit to the current one . It would mean a ?pair of devices between them covering 0-3gkz) with satisfactory performance for around ?100 ($120) - a bargain. Although there are various handheld devices around now ( I have an old Deepace KC901s at ?1300), they are much more expensive, bigger, and/or do not have as good a performance ( eg rbw of 2.8khz).

I understand the worries concerning ?possible complaints of unexpected performance, but most buying this kit will have some appropriate insight and knowledge and should understand about limitations of the kit. I am sure I am not the only one to use a spectrum analyser to measure leakage from the microwave but most users have far more sophisticated tasks for these devices. I would have thought that the nanovna would be far more challenging than a spectrum analyser to use for those without a professional background but they seem to sell like wildfire ( as does the present Tinysa).