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The spectra below have been taken with a netmca-3 during a 2 month pre-purchase evaluation period of their netMCA at the institute Jozeph Stefan in Ljubljana, Slovenia.
We would like to thank everyone involved there for the effort and for the kind permission they gave us to publish the data - and wish them many years of efficient use of their netMCAs.
Each spectrum is available in 4 formats:
.spc - this is the netMCA native format and contain the complete infortmation,
.asp - plain ASCII channel data only,
.spe - ASCII format including live time, energy calibration etc.,
.spm - binary nucleus-like format, includes energy calibration.

The spectra cover practically all tests to which the netMCA was subjected during the evaluation period (which were chosen by the people there). On all occasions it performed excellently, delivering results better than their old NIM system in terms of resolution, counting loss compensation over a wide range of input count rates and it matched their analog system in terms of extended low energy range covering <8keV to >2.7MeV in a single spectrum (their NIM system had been custom enhanced to perform well at that).
The whole test was practically "plug and play", for their second detector the netmca never even was given a source it normally would need to adjust its PZ.
We were monitoring the entire procedure over the internet from our facility in Sofia, Bulgaria - the netmca was with its online support feature on so we had full access to it all the time.

In all spectra they had a pulser feeding into the detector preamp which was delivering 9.9 cpS; its peak is at the top end of each spectrum, around channel 8050 or somewhat above (all spectra being 8192 channels long).

Weak 60Co with a 1.6kcpS 241Am. Counting loss error in the pulser peak is <0.3%
Some very weak source, not much except the pulser coming in.
Another very weak source with some 7Be in the sample.
Yet another sample with some 7Be in it.
Some weak source (the background in their shield?).
Some other weak source.
A coctail with some 60Co, 137Cs, 57Co, 109Cd, 88Y, 241Am and some more
Pretty similar to ijscoct1 (same source?) but with a detector with a Be window, i.e. with an extended low energy range
Some other low cpS coctail with plenty of x-ray lines down, apparently intended to check the low energy range - which is quite good to even below 8keV - that at a 2.7MeV upper spectrum limit.
The above (ijscoc3) spectrum scaled twice for illustrative purposes in answer to a question of halving the gain.
Taken with their old NIM system and emailed to us; same sample as above (according to them), evidently taken apr. 500 days earlier. Used as a basis for our claim for better resolution achieved with the netMCA.
Weak 60Co source and 9.9cpS pulser plus a 3.8kcpS 241Am. Peak for the pulser line (top of the spectrum) - 0.33 channels @ 8k, practically undetectable. Resolution degradation well below 0.1 keV; counting loss compensated to < 1.7% error (seen at the 9.9 cpS peak pulse).
Comparison of two spectra taken simultaneously with the netMCA and their NIM equipment.
Some apr. 100 cpS source measured with the same Be windowed detector as the others but at twice the gain. Just a little better resolution because of less quantization etc. noise, just as one would expect.
Some apr. 350 cpS source measured with the same Be windowed detector as the others but at twice the gain. Just a little better resolution because of less quantization etc. noise, just as one would expect. Much better resolution than with their old NIM equipment, 1.97 vs. 2.2 keV @ 1332.5 .
Taken at very low gain, so that the full spectrum range is up to 5.6MeV, 16k channels.

A weak 60Co with a 1.6kcpS 241Am. Counting loss error in the pulser peak is <0.3%
ijsamco1.spc screenshot
ijsamco1.spc - DPS/nuvi (netMCA) object format
ijsamco1.spm - Nucleus-2 format
ijsamco1.asp - Plain ASCII format
ijsamco1.spe - ASCII format with some details

Some very weak source, not much except the pulser coming in.
ijssrc2.spc screenshot
ijssrc2.spc - DPS/nuvi (netMCA) object format
ijssrc2.spm - Nucleus-2 format
ijssrc2.asp - Plain ASCII format
ijssrc2.spe - ASCII format with some details

Another very weak source with some 7Be in the sample.
ijs7be.spc screenshot
ijs7be.spc - DPS/nuvi (netMCA) object format
ijs7be.spm - Nucleus-2 format
ijs7be.asp - Plain ASCII format
ijs7be.spe - ASCII format with some details

Yet another sample with some 7Be in it.
ijs7be2.spc screenshot
ijs7be2.spc - DPS/nuvi (netMCA) object format
ijs7be2.spm - Nucleus-2 format
ijs7be2.asp - Plain ASCII format
ijs7be2.spe - ASCII format with some details

Some weak source (the background in their shield?).
ijswks1.spc screenshot
ijswks1.spc - DPS/nuvi (netMCA) object format
ijswks1.spm - Nucleus-2 format
ijswks1.asp - Plain ASCII format
ijswks1.spe - ASCII format with some details

Some other weak source.
ijswks2.spc screenshot
ijswks2.spc - DPS/nuvi (netMCA) object format
ijswks2.spm - Nucleus-2 format
ijswks2.asp - Plain ASCII format
ijswks2.spe - ASCII format with some details

A coctail with some 60Co, 137Cs, 57Co, 109Cd, 88Y, 241Am and some more.
ijscoct1.spc screenshot
ijscoct1.spc - DPS/nuvi (netMCA) object format
ijscoct1.spm - Nucleus-2 format
ijscoct1.asp - Plain ASCII format
ijscoct1.spe - ASCII format with some details

Pretty similar to ijscoct1 (same source?) but with a detector with a Be window, i.e. with an extended low energy range.
ijswcoc2.spc screenshot
ijswcoc2.spc - DPS/nuvi (netMCA) object format
ijswcoc2.spm - Nucleus-2 format
ijswcoc2.asp - Plain ASCII format
ijswcoc2.spe - ASCII format with some details

Some other low cpS coctail with plenty of x-ray lines down, apparently intended to check the low energy range - which is quite good to even below 8keV - that at a 2.7MeV upper spectrum limit.
ijscoc3.spc screenshot
ijscoc3.spc - DPS/nuvi (netMCA) object format
ijscoc3.spm - Nucleus-2 format
ijscoc3.asp - Plain ASCII format
ijscoc3.spe - ASCII format with some details

Taken with their old NIM system and emailed to us; same sample as above (according to them), evidently taken apr. 500 days earlier. Used as a basis for our claim for better resolution achieved with the netMCA. The typical for analog systems low-end oscillation can be seen before it is apparently cut off with the LLD.
ijsold.spc screenshot
ijsold.spc - DPS/nuvi (netMCA) object format
ijsold.spm - Nucleus-2 format
ijsold.asp - Plain ASCII format
ijsold.spe - ASCII format with some details

Weak 60Co source and 9.9cpS pulser plus a 3.8kcpS 241Am. Peak shift for the pulser line (top of the spectrum) - 0.33 channels @ 8k, practically undetectable. Resolution degradation well below 0.1 keV; counting loss compensated to < 1.7% error (seen at the 9.9 cpS peak pulse).
ijs4kam.spc screenshot
ijs4kam.spc - DPS/nuvi (netMCA) object format
ijs4kam.spm - Nucleus-2 format
ijs4kam.asp - Plain ASCII format
ijs4kam.spe - ASCII format with some details

These two spectra were acquired simultaneously with the netMCA and their NIM equipment (the netMCA using the "timing" output of the detector preamp). The time information is lost because we got the two spectra evaluated there emailed back to us in ASCII format; however, the netMCA spectrum is pretty much the same as this one (same spectrum recorded a bit earlier or later).
The netMCA has >5% better resolution at 1332.5 keV (2.09 vs. 2.2) and is >12% better at 59.54 keV (0.81 vs. 0.93). The energy range of the netMCA is also better, it sees a peak at 7.9 keV which the analog system does not see (at 7.9keV it only sees its own noise/oscillation). The NIM spectrum had to be calibrated by two points to compensate the offset-0 of its ADC, on the netMCA a 1 point calibration was enough (it has no offset-0 by design).
netMCA vs. NIM low range
Intercomparison spectrum taken by the netMCA:
ijsfbnmc.spc - DPS/nuvi (netMCA) object format
ijsfbnmc.spm - Nucleus-2 format
ijsfbnmc.asp - Plain ASCII format
ijsfbnmc.spe - ASCII format with some details

Intercomparison spectrum taken by their NIM equipment:
ijsfbnim.spc - DPS/nuvi (netMCA) object format
ijsfbnim.spm - Nucleus-2 format
ijsfbnim.asp - Plain ASCII format
ijsfbnim.spe - ASCII format with some details

nmcnimcp.xls - a comparative analysis they did on the two spectra in .xls format and kindly emailed us.

Some apr. 100 cpS source measured with the same Be windowed detector as the others but at twice the gain. Just a little better resolution because of less quantization etc. noise, just as one would expect.
ijshg1.spc screenshot
ijshg1.spc - DPS/nuvi (netMCA) object format
ijshg1.spm - Nucleus-2 format
ijshg1.asp - Plain ASCII format
ijshg1.spe - ASCII format with some details

Some apr. 350 cpS source measured with the same Be windowed detector as the others but at twice the gain. Just a little better resolution because of less quantization etc. noise, just as one would expect. Much better resolution than with their old NIM equipment, 1.97 vs. 2.2 keV @ 1332.5 and 0.815 vs. 0.97 @ 88keV .
ijshg2.spc screenshot
ijshg2.spc - DPS/nuvi (netMCA) object format
ijshg2.spm - Nucleus-2 format
ijshg2.asp - Plain ASCII format
ijshg2.spe - ASCII format with some details

Scaled twice mathematically by using the nuvi "scale" command from ijscoc3; to illustrate what the spectrum would be at twice lower gain setting of the netmca (therew as such a question). ijscoc3h.spc screenshot
ijscoc3h.spc - DPS/nuvi (netMCA) object format
ijscoc3h.spm - Nucleus-2 format
ijscoc3h.asp - Plain ASCII format
ijscoc3h.spe - ASCII format with some details

Like ijscoc3 but taken at half the gain as a 16 k spectrum - i.e. the full spectrum range is 5.6 MeV. The resolution is worsening very little, despite using 1/2 the dynamic range compared to ijscoc3 and 1/4 the dynaminc range compared to ijshg1. Notably the usable range is 12 keV to 5.6MeV.
ijs16k1.spc screenshot
ijs16k1.spc - DPS/nuvi (netMCA) object format
ijs16k1.spm - Nucleus-2 format
ijs16k1.asp - Plain ASCII format
ijs16k1.spe - ASCII format with some details

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