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Sunday, 30 October 2016

UPDATE: New version of SMA Simple Spectrum Analyser Software


I just uploaded a new version of the SMA Simple Spectrum Analyser software!

This versions brings support to both ADF4350 and ADF4351 versions. Finally!

As you should know by now:
  • ADF4350 = 138MHz - 4.4GHz
  • ADF4351= 35MHz-4.4GHz
The NWT4000 versions use one of both frequency ranges, also. They just use two of those IC's, instead of just one in the "SMA Simple" versions.

I have not tested this, since I don't own a ADF4351 version, but I think it should work fine. Please let me know if it does work, indeed.

Download link:


Licensing of the SMA Simple Spectrum Analyser


I made up my mind about licensing the SMA Spectrum Analyser.

  1. The software is free for anyone requesting an activation code. I will not make it totally free, without a licensing mechanism, because I do not want to do free support for the Chinese manufacturers/sellers of the SMA device. They ship their devices with a shareware (WinNWT) without prior consent of the author!
  2. I will give out activation codes valid up to three months. The expiry dates will be:
    1. March, 31st
    2. June, 30th
    3. September, 30st
    4. December, 31st
  3. You will always get the next expiry date.
  4. You can ask for new codes as many time as you want.
  5. You can request more than one activation code.
  6. Depending upon my free time / personal life, issuing the activation codes can take minutes to days - no warranty what so ever.
  7. The activation codes work with any future release.
  8. I will accept donations of 10 Euro / 10 US$ / 10£. In return I will issue a permanent activation code (31.12.2099). I am not sure how to do that with PayPal, so this is not working at the time being. I will not provide any extra support, bug fixing, etc. to people who donated: the donation is only for the permanent activation.

New version: SMA Simple Spectrum Analyser


One user (thanks Mark), pointed out that the window of the SMA Simple Spectrum Analyser wouldn't fit on his screen. Because I use FullHD on all my PC's, I never thought about this.

Anyway, his request was more than reasonable and most spectrum analysers have their controls on the right side of the screen, so I moved everything to that position.

The result looks like this:

Hopefully, the software can be used on screens with lesser vertical resolution.

By the way and because this is a frequent question: "why is the window not sizeable?" or "please make the spectrum screen bigger".

The answer is: the spectrum screen is exactly 1000 pixels wide, because this way I can render 1000, 500, 250, 200 and 100 samples without having to mess around with non-integer values of the Y-coordinate!

This is actually a similar, why the Siglent SSA3021X spectrum analyser uses exactly 751 data points (see discussion here: You determine how many data points/samples you want (read: can) to capture in a reasonable time and you select an appropriate screen resolution. If you wanted to render more pixels, these would have to be interpolated: that doesn't add anything useful and costs time, especially if non-integer numbers arise.

You can download the latest release here:

(NOTE: this version was replaced by the 2016-10-30b version!)

Have fun!

Saturday, 29 October 2016

Important warning for the SMA Simple Spectrum Analyser


This is to warn you: you need to attenuate the input signal to a level compatible with the SMA device!

Also, you must use a DC blocker if a voltage I present, for example if you are connecting the SAT cable from the Loop Through port of your receiver.

Please remember that TV, CATV and SAT cables often carry a voltage, used to feed amplifiers, switches and LNB.

On amateur radio antennas, make sure that you are not too close to a transmitter: the signal power might be too high. Use an attenuator!

Otherwise chances are you kill the IAM-81008 IC! On the PCB this is an SO-8 package IC with "M810" printed on it. This has of course happend to me...

Fortunatly, the IC can be ordered on eBay or AliExpress. To exchange it, one can use a hot air soldering station.


EDIT: It is the M810 that gets killed, not the ADF4350 as mentioned previously!

Monday, 24 October 2016

VU+ DUO repair: fixed tuner problems!

I have several satellite dishes, but two are special: a 100cm with multi feed and a 80cm with just one LNB. The cables go down to a multi switch and from there one cable to each of 8 rooms.

In the past, the multi switch got broken (the power source literally burned) and was repaired, but over the years I started to struggle with corrosion on the cables on the roof. More precisely, the cables come from the LNB and attach to the cable going down by means of an F-type male-male connector. This connector gets corroded and after some years/month, needs to be replaced and the corroded part of the cable must be cut off. This annoys me a lot, because the length of the installed cable going down to the distribution box is getting shorter every year.

This whole thing started of wrong: when I was building the house, I wanted to go cheap and imagined having the multi switch on the roof. Hence I only passed down 8 cables. After two multi switches breaking down due to humidity, rain, sun, heat, cold, etc., I accepted that the multi switch really needed to go inside the house. Naturally it was protected in a box, but it was not ventilated and, well, it did not work. One of the drawback was that I only had a total of 9 cables, which meant that I could only pass the signal of two satellites (19.2E + 13.0E) and one band of the third satellite (30.0W), when originally it was planned to have 19.2E, 13.0E, 30.0W and 28.2E.

Also, this is why I ended up with too short cables on the roof and the requirement to use the F-type male-male connector.

Because I have other dishes, two of which are motorized, and all of them go to my shack, where I pass my time messing around with TV, CATV and SAT equipment, I haven't lately bothered to fix the fact that in the bedroom I wasn't really receiving anything anymore. I have been spending awake time using a tablet instead.

Anyway, this weekend I decided to sort this out once for all. I went to the roof and replaced the QUADRO-LNB's with QUATTRO-LNB's and redone all the cables. I put a simple DiSEqC-1.0 switch and used a single cable to the bedroom. I wasn't using SAT on any other TV anyway. Also, this solution gives me the option to pass SAT to 3 further rooms. I removed the multi switch, which was at the end of its life cycle, anyway.

When I finally tested the now full 4 satellites in the bedroom: nothing!
Still no reception... :(

Could I have a fault in any cable? Up to the roof, replaced one cable I had reused from the previously installed ones.

Tested again: nothing.

Took on of my TV analysers and checked: all OK. Could the TV analyser have a much more sensitive tuner?


Took another SAT receiver (AZBox Ultra HD) and... 3800 channels.

So after all, the culprit had to be the VU+ DUO sat receiver, which I have for some 4-6 years.

I did a full RESET and got about 500 channels. Far too few, but everything else was working fine.

Started reading in the forums and found out that this is a common problem: missing the High-Band/Horizontal channels, due to dried capacitor! This causes the required 16V for upper band channels to not be generated properly.

*** Repair starts here ***

Changed a 100uF capacitor (C852) and... nothing.
Changed two 1000uF capacitors (C848 and C819) and... IT WORKED AGAIN!

*** Repair ends here ***

  • Spend 1 day on the roof for nothing.
  • Changing the whole SAT reception distribution for nothing (OK: now I have 4 full satellites, in one room, with option for a total of 4 rooms, instead of having 2+1 satellites in 8 rooms).
  • Did a repair in 1 hour (can be reproduced now in about 15 minutes), with a total cost of 3 capacitors worth 1.20 Euro.


I will now buy a complete set of capacitors and replace them all. It was sheer luck to have the 100uF and 1000uF capacitors lying around, but I did not have enough of them and i lack the 220uF ones, too.

Also, the ones I used are fairly old and probably sub-standard, so they will be replaced again.

Anyway, that saved me from having to buy a new VU+ receiver (they are really good products).


Wednesday, 12 October 2016

New update: SMA Simple Spectrum Analiser Software


Today I added what I consider the remaining fundamental spectrum analyser functionality that my software was missing:

  • Direct input of the center frequency
  • Direct input of the frequency span
  • Quick zoom in/out of the frequency span 

Also, I cleaned up the user interface. Hope you like it!

As always, you can download the software here:

Have fun!

Tuesday, 11 October 2016

Siglent SSA3021X

In case you were wondering were some of my inspiration for the SMA Simple Spectrum Analyser software came from: it came from my recently purchased Siglent SSA3021X!

I always wanted to own a REAL spectrum analyser and Siglent made it possible by offering a real deal... For 1449 Euro (ex. VAT) you get a 9kHz to 2.1GHz spectrum analyser.

I took some screenshots:

Here I am looking at the local DVB-T transponder, to the right are the LTE transponders.

Same range, but with the waterfall diagram!

Zooming into the DVB-T transponder.

And measuring the channel power!

 In case you missed it, I have a Youtube video showing the SSA3021X in action. I am using the included EasySpectrum software to remote control the spectrum analyser!

More information:

Long-term spectrum monitoring


I left the SMA Simple Spectrum Analyser software running with the waterfall diagram in the large upper window, rendering the Astra 19.2E satellite.

It takes about 20 Minutes to render the complete graph at 500 samples (500 lines).

This was the result:

The horizontal line shows where the waterfall graph is being updated. I don't scroll the graph, instead I refresh it from top to bottom.

The region marked with rectangle 1 shows the loss in gain due to the fact that it started to rain...
The region marked with rectangle 2 shows something interesting: a very small transponder drops is signal power, while a similar transponder raises signal power. If you look to where the horizontal line is, you see the frequency difference.

Sometimes it can be usefull to run a long-term measurement on the spectrum to visualize drifts, trends, sporadic transmissions, etc.!

Changing the SMA Simple Spectrum Analyser software to 1000 samples, a complete run with the waterfall diagram in the main window will take about 45 minutes:


Monday, 10 October 2016

SMA Simple Spectrum Analyzer Software: small update

I updated the rendering engine of the small graphics window. It now uses the same code as the main graphic window. This makes the software more consistent and it is finally possible to do an ALT+PRTSCN to grab the window contents and paste it to Paint, Word or whatever software you are using for your reports.

Download the latest release here:

Tuesday, 4 October 2016

Update: SMA Simple Spectrum Analyzer - New graphics engine!


I have been working on the graphics engine again.

The improvements are:

  • The spectrum is drawn with a best fit curve, instead of connecting the sampled points with straight lines. This gives a much nicer representation of the spectrum, especially when less samples are used.
  • I managed to improve the refresh rate slightly. The bottleneck is now the hardware of the SMA Spectrum Analyzer - I don't think I can squeeze more speed out of it.
  • The spectrum can be rendered with shading ("solid curve"). This makes the simultaneous view of LIVE, MIN, MAX and AVG much nicer.
  • I *finally* implemented a proper colour map for the waterfall diagram.

Local DVB-T transponder at 754MHz with LTE transponders to the right.
The spectrum shows three traces: LIVE, MIN and MAX.

Live spectrum of the CATV band with new "Shaded Spectrum" option activated.

Waterfall diagram of WLAN traffic in the 2.4GHz band.

As always, go ahead and download the lates release here:

Make sure to watch the new video:


Sunday, 2 October 2016

Update: SMA Simple Spectrum Analyzer


Well, nothing big changed, but still I find it convenient...
...the software now shows the RBW value!

Because the SMA Simple Spectrum Analyzer 138MHz-4.4GHz works with number of samples at a given start frequency and frequency increment, it doesn't make much sense in having the user specifying the RBW directly.

I made the software work with a 1000 pixel wide window, which allows for integer inbterpolation of 1000, 500, 250, 200 and 100 samples per scan. No you know why!

But I was missing the information of what RBW I was looking at, so today I decided to add this missing information.

Grab the latest release at:

Have fun!