Test data for Urukul

[TheCakeIsAPi]

I took some detailed test data to measure power levels and harmonics. I think it may be useful to others. I suggest creating a place on the Wiki to catalog this and other such data for each piece sinara-hw.

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Readings for urukul0_ch0, AD9910 model, Urukul v1.3, s/n TS 92/19 0027, with 125 MHz external clock from Wenzel 501-31911, via Mini-Circuits ZB4PD-52-20W-S+ power splitter, measured on Keysight N9343C (which only has spec'd response from 1 MHz to 13.6 GHz). Attenuation and reference level of the N9343C were set to minimum levels that support each measurement. All readings were allowed to average until stabilized to +/-0.05 dBm

At attenuation = 0.0 dB

Setpoint [MHz]	Fundamental [dBm]	1st [dBm]	2nd [dBm]	3rd [dBm]	4th [dBm]	5th [dBm]	6th [dBm]	7th [dBm]	8th [dBm]
0.1	-21.14	-59.03	-54.93	-93.07	-73.38	-94.07	-84.78	-91.77	-96.61
0.5	4.51	-15.45	-11.61	-25.02	-24.35	-51.70	-35.14	-34.46	-37.85
1	7.67	-16.80	-12.32	-18.27	-29.25	-30.87	-34.51	-39.28	-39.84
10	10.67	-12.69	-13.94	-26.12	-27.76	-36.11	-55.32	-43.85	-42.65
20	10.86	-24.90	-13.65	-22.87	-28.67	-47.68	-35.85	-35.45	-38.48
50	10.74	-14.18	-15.01	-27.57	-29.01	-38.05	-51.52	-44.53	-42.71
100	9.70	-33.59	-16.72	-34.36	-26.81	-40.14	-41.07	-43.88	-56.89
200	8.97	-22.22	-16.23	-24.89	-30.49	-37.97	-37.79	-38.80	-40.14
300	8.27	-19.17	-19.51	-29.80	-34.75	-38.90	-51.92	-53.38	-57.95
400	7.68	-17.82	-21.60	-33.04	-37.80	-50.37	-57.45	-59.80	-64.68
500	-1.80	-41.57	-51.71	-72.36	-89.35	-91.63	-93.15	-84.54	-107.57

At attenuation = 10.0 dB

Setpoint [MHz]	Fundamental [dBm]	1st [dBm]	2nd [dBm]	3rd [dBm]	4th [dBm]	5th [dBm]	6th [dBm]	7th [dBm]	8th [dBm]
0.1	-27.06	-81.35	-62.09	-97.37	-84.11	-103.78	-91.37	-100.48	-104.22
0.5	-3.2	-37.82	-52.21	-66.76	-77.86	-85.92	-86.37	-97.59	-120.76
1	-0.43	-34.47	-47.80	-75.28	-86.45	-101.91	-93.22	-96.14	-106.71
10	1.95	-31.04	-28.23	-51.76	-57.29	-76.26	-78.15	-83.85	-80.20
20	2.10	-33.05	-28.30	-54.50	-52.31	-72.39	-70.96	-82.98	-82.58
50	1.89	-33.24	-28.50	-52.67	-48.35	-74.77	-77.26	-79.33	-73.58
100	0.80	-38.51	-63.22	-61.73	-71.97	-97.45	-97.67	-107.40	-93.03
200	0.05	-38.25	-42.16	-63.01	-84.55	-82.66	-108.85	-116.62	-99.45
300	-0.51	-35.91	-48.83	-82.43	-100.53	-111.79	-118.62	-120.05	-97.72
400	-1.20	-38.37	-49.77	-89.45	-74.66	-108.12	-116.75	-114.08	-102.29
500	-11.20	-61.47	-77.59	-74.73	-100.23	-93.12	-99.83	-86.71	-112.63

At attenuation = 20.0 dB

Setpoint [MHz]	Fundamental [dBm]	1st [dBm]	2nd [dBm]	3rd [dBm]	4th [dBm]	5th [dBm]	6th [dBm]	7th [dBm]	8th [dBm]
0.1	-31.06	-82.29	-68.34	-109.04	-92.48	-111.23	-99.94	-109.85	-112.36
0.5	-11.99	-56.69	-71.73	-95.76	-101.86	-114.37	-102.81	-106.94	-116.72
1	-9.94	-54.54	-56.49	-89.12	-105.94	-110.93	-102.79	-107.01	-117.29
10	-7.89	-50.19	-57.35	-91.36	-97.88	-107.95	-103.53	-96.04	-108.26
20	-7.79	-52.72	-58.03	-90.75	-99.82	-102.07	-101.55	-104.73	-103.31
50	-7.96	-52.36	-59.26	-84.44	-87.55	-86.88	-97.76	-92.61	-83.19
100	-9.04	-57.40	-61.76	-78.50	-91.80	-117.64	-107.40	-112.64	-102.07
200	-9.73	-57.39	-72.31	-72.66	-93.26	-95.95	-125.22	-122.35	-130.24
300	-10.27	-58.65	-74.60	-109.24	-107.74	-115.75	-125.36	-124.54	-98.86
400	-10.94	-59.62	-79.36	-98.48	-74.72	-111.95	-119.18	-114.63	-104.34
500	-21.00	-78.52	-99.07	-74.91	-99.55	-92.91	-103.02	-87.33	-114.87

At attenuation = 31.5 dB

Setpoint [MHz]	Fundamental [dBm]	1st [dBm]	2nd [dBm]	3rd [dBm]	4th [dBm]	5th [dBm]	6th [dBm]	7th [dBm]	8th [dBm]
0.1	-37.89	-85.04	-77.41	-122.04	-114.29	-115.58	-110.65	-120.06	-123.70
0.5	-22.38	-71.24	-89.84	-107.81	-108.76	-127.83	-114.12	-118.34	-127.07
1	-21.01	-72.10	-90.08	-111.97	-111.30	-127.43	-114.38	-118.07	-128.06
10	-19.22	-72.13	-90.74	-110.14	-105.28	-114.04	-113.51	-94.85	-116.15
20	-19.28	-75.95	-94.72	-91.71	-107.55	-112.85	-112.24	-116.33	-114.02
50	-19.27	-74.93	-92.21	-95.77	-101.06	-97.92	-108.30	-103.60	-93.96
100	-20.27	-79.05	-87.48	-89.73	-104.00	-117.98	-112.12	-110.51	-105.80
200	-21.19	-78.33	-106.81	-82.70	-92.31	-109.93	-133.86	-120.94	-102.95
300	-21.58	-80.96	-112.44	-110.40	-108.11	-115.68	-122.51	-125.25	-99.63
400	-22.44	-82.73	-105.55	-98.03	-74.84	-113.93	-119.41	-114.93	-104.55
500	-31.73	-93.37	-99.74	-75.03	-99.27	-92.84	-104.14	-87.46	-116.22

[sbourdeauducq]

Thanks!

[jordens]

With "1st" you mean the first overtone but the second harmonic, right?

[TheCakeIsAPi]

@jordens yes. Fundamental = setpoint. 1st = 2 x setpoint. 2nd = 3 x setpoint. Sorry if that was unclear. I did also see some other peaks that were on occasion bigger than the nearby harmonics, but I couldn't think of a decent way to tabularize that, so those are not recorded here.

[dhslichter]

Thanks for the data, @TheCakeIsAPi!

I did also see some other peaks that were on occasion bigger than the nearby harmonics, but I couldn't think of a decent way to tabularize that, so those are not recorded here.

One way would be to have a column for "largest spur", so that people can see the spur-free dynamic range. Another thing that might be nice (for a final table in a wiki) would be to convert the harmonics into dBc (relative to fundamental), to help save on the mental gymnastics of the doing the math each time.

[jordens]

Some of the the data look suspicious to me. E.g.

• A -26.4 dBc third harmonic at 100 MHz, 0 dB is much worse than what I measured way back (AD9912 v1.0, -53.5 dBc third harmonic at 80 MHz, 0 dB).
• At 10 dB attenuation for 10, 20, 50 MHz the third harmonic is 20-35 dB worse than for both 1 or 100 MHz.
• At 0 dB attenuation the high harmonics of 400 MHz (2.8, 3.2, 3.6 GHz) at -57, -60, -65 dBm (w.r.t. 8 dBm fundamental).
• Many measurements appear to be the dynamic range/floor of the spectrum analyzer and not the power of the harmonics.

Attenuation and reference level of the N9343C were set to minimum levels that support each measurement

Minimizing input attenuation (below the typical/automatic min(0 dBm, ref_level) + 10 dB) in spectrum analyzers is risky. Sure you didn't create harmonics yourself?