Receiver Performance Tests - Revision history

OZ1HFT: catspec

2010-01-26T18:35:52Z

catspec

OZ1HFT: +cat

2010-01-25T18:56:32Z

+cat

W9KFB: added reference:Mercury - intermodulation (IMD) tests

2009-11-04T03:54:43Z

added reference:Mercury - intermodulation (IMD) tests

W9KFB: /* SSB Phase Noise */ Added caution on using 10 MHz oscillators

2009-11-02T00:08:35Z

‎SSB Phase Noise: Added caution on using 10 MHz oscillators

W9KFB: /* Third-Order Intercept Tests */ correct call

2009-10-31T08:39:14Z

‎Third-Order Intercept Tests: correct call

VK2NRA: change to media file type

2009-10-31T06:06:04Z

change to media file type

W9KFB: corrected reference to file uploaded.

2009-10-31T02:48:14Z

corrected reference to file uploaded.

W9KFB: Added reference to pdf doc uploaded.

2009-10-31T02:45:35Z

Added reference to pdf doc uploaded.

W9KFB: /* Third-Order Intercept Tests */ Added first text.

2009-10-31T01:53:56Z

‎Third-Order Intercept Tests: Added first text.

W9KFB: /* IMD Dynamic Range */ Put in the word "about" instead of "will be"

2009-10-30T02:27:03Z

‎IMD Dynamic Range: Put in the word "about" instead of "will be"

← Older revision		Revision as of 18:35, 26 January 2010
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	This file compares measurements taken at W9KFB's lab, Walter, HB9AJG's lab, and the ARRL Lab (Flex 3000 data) [[media:ARRL FLX3000&HB9AJG tests.pdf ]].		This file compares measurements taken at W9KFB's lab, Walter, HB9AJG's lab, and the ARRL Lab (Flex 3000 data) [[media:ARRL FLX3000&HB9AJG tests.pdf ]].

−	[[Category:~~Hardware~~]]	+	[[Category:Mercury]]

← Older revision		Revision as of 18:56, 25 January 2010
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	This file compares measurements taken at W9KFB's lab, Walter, HB9AJG's lab, and the ARRL Lab (Flex 3000 data) [[media:ARRL FLX3000&HB9AJG tests.pdf ]].		This file compares measurements taken at W9KFB's lab, Walter, HB9AJG's lab, and the ARRL Lab (Flex 3000 data) [[media:ARRL FLX3000&HB9AJG tests.pdf ]].
		+
		+	[[Category:Hardware]]

@@ Line 30: / Line 30: @@
 [[Image:Image-HPSDR IMD DR test block Dia.jpg|thumb|300px|A block diagram of the IMD dynamic range test setup]]
 IMD Dynamic Range measures the effect of two-tone IMD on a HPSDR receiver. IMD is the production of spurious responses that results when two or more signals mix. IMD occurs in any receiver when signals of sufficient magnitude are present. IMD Dynamic Range is the difference, in dB, between the noise floor and the strength of two equal incoming signals that produce a third-order product 3 dB above the noise floor. For more information on IMD Dynamic Range measurement, see the 2009 ARRL Handbook, Test procedures, Chapter 25, page 25.43.
-''Important note: To get good performance with respect to the IMD Dynamic Range tests, be sure to check "Dither Enabled" and "Random Enabled" in the Setup > HPSDR > Mercury Options panel''. If this is not done your IMD Dynamic Range will be reduced by about 50%.
+''Important note: To get good performance with respect to the IMD Dynamic Range tests, be sure to check "Dither Enabled" and "Random Enabled" in the Setup > HPSDR > Mercury Options panel''. If this is not done your IMD Dynamic Range will be reduced by about 50%. Reference:[[Mercury - intermodulation (IMD) tests]].
 ==== Third-Order Intercept Tests====

@@ Line 14: / Line 14: @@
 [[Image:MDS & SSB Phase Noise Test.jpg|thumb|300px|Block Diagram of MDS and SSB Phase Noise Measurement Setup]]
-[[Image:HPSDR SSB Phase Noise.jpg|thumb|300px|Actual measurement of the SSB Phase Noise on a HPSDR Mercury with the Pre-Amp OFF by W9KFB 10/26/2009. Note the output limit for the oscillator was reached at an ofset of 1KHz.]]
+[[Image:HPSDR SSB Phase Noise.jpg|thumb|300px|Actual measurement of the SSB Phase Noise on a HPSDR Mercury with the Pre-Amp OFF by W9KFB 10/26/2009. Note the output limit for the oscillator was reached at an offset of 1KHz.]]
-[[Image:HPSDR SSB Phase Noise PA=ON.jpg|thumb|300px|Actual measurement of the SSB Phase Noise on a HPSDR Mercury with the Pre-Amp ON, CW BW=100 by W9KFB 10/26/2009. Note the the A/D Overload limit was reached at an offset frequency of 1 KHz.]]
 [[Image:HPSDR PN.jpg|thumb|300px|Measurement of Mercury's SSB Phase Noise by Marco IK1ODO / AI4YF and some comparables]]
-The SSB Phase Noise tests require a very low phase noise oscillator to run the tests. Most synthesized oscillators will not be good enough. Before you choose an oscillator to do the testing, check its SSB phase noise specifications. If the oscillator has a worst case spec of greater than -130 dBc/Hz, find one that is better as your noise measurement results will never be better than the test oscillator noise level.
+The SSB Phase Noise tests require a very low phase noise oscillator to run the tests. Most synthesized oscillators will not be good enough. Before you choose an oscillator to do the testing, check its SSB phase noise specifications. If the oscillator has a worst case spec of greater than -130 dBc/Hz, find one that is better as your noise measurement results will never be better than the test oscillator noise level. Also note that in choosing a test oscillator for SSB Phase Noise measurement, 10 MHz should be avoided as there is usually a 10 MHz signal from the Mercury clock source that will interfere with measurement of SSB Phase Noise close to the 10MHz carrier signal.
 #Use the MDS obtained per the process above as A0, then tune away from the signal until you can't distinguish a tone in the noise or to your first defined offset frequency. At this frequency, increase the amplitude of the signal until the displayed amplitude (using the PowerSDR meter set to "SigAvg") is the same as A0 plus 3 dB (the MDS will be a minus number, so this number will be 3 dB lower in absolute value), note the frequency f1, and then go back to f0 and measure the amplitude A1 using the PowerSDR meter set to "SigAvg".
 #To calculate SSB Phase Noise use this equation from KI6WX's March and April, 1988, QST article (The 2009 and earlier ARRL Handbooks have a missing minus sign in the equation): L(f)=A1-A0-10Log(BWnoise), Where L(f)= SSB phase noise in dBc/Hz; A1= The attenuation required at the offset frequency for the same noise level as A0 plus 3 dB; A0= MDS; and BWnoise= The CW bandwidth used during the test.

← Older revision		Revision as of 08:39, 31 October 2009
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	The "IMD Level" is a target level of -97 dBm for all HPSDR receiver designs.		The "IMD Level" is a target level of -97 dBm for all HPSDR receiver designs.

−	This file compares measurements taken at W9KFB's lab, Walter, ~~DJ6AJC~~'s lab, and the ARRL Lab (Flex 3000 data) [[media:ARRL FLX3000&HB9AJG tests.pdf ]].	+	This file compares measurements taken at W9KFB's lab, Walter, HB9AJG's lab, and the ARRL Lab (Flex 3000 data) [[media:ARRL FLX3000&HB9AJG tests.pdf ]].

← Older revision		Revision as of 06:06, 31 October 2009
Line 43:		Line 43:
	The "IMD Level" is a target level of -97 dBm for all HPSDR receiver designs.		The "IMD Level" is a target level of -97 dBm for all HPSDR receiver designs.

−	This file compares measurements taken at W9KFB's lab, Walter, DJ6AJC's lab, and the ARRL Lab (Flex 3000 data) [[~~Image~~:ARRL FLX3000&HB9AJG tests.pdf ]].	+	This file compares measurements taken at W9KFB's lab, Walter, DJ6AJC's lab, and the ARRL Lab (Flex 3000 data) [[media:ARRL FLX3000&HB9AJG tests.pdf ]].

← Older revision		Revision as of 02:48, 31 October 2009
Line 43:		Line 43:
	The "IMD Level" is a target level of -97 dBm for all HPSDR receiver designs.		The "IMD Level" is a target level of -97 dBm for all HPSDR receiver designs.

−	This file compares measurements taken at W9KFB's lab, Walter, DJ6AJC's lab, and the ARRL Lab (Flex 3000 data) [[~~ARRL_FLX3000~~&~~HB9AJG_tests~~.~~pdf‎~~ ]].	+	This file compares measurements taken at W9KFB's lab, Walter, DJ6AJC's lab, and the ARRL Lab (Flex 3000 data) [[Image:ARRL FLX3000&HB9AJG tests.pdf ]].

← Older revision		Revision as of 02:45, 31 October 2009
Line 42:		Line 42:

	The "IMD Level" is a target level of -97 dBm for all HPSDR receiver designs.		The "IMD Level" is a target level of -97 dBm for all HPSDR receiver designs.
		+
		+	This file compares measurements taken at W9KFB's lab, Walter, DJ6AJC's lab, and the ARRL Lab (Flex 3000 data) [[ARRL_FLX3000&HB9AJG_tests.pdf‎ ]].

← Older revision		Revision as of 01:53, 31 October 2009
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	==== Third-Order Intercept Tests====		==== Third-Order Intercept Tests====
		+	The recommended method of calculating the third-order intercept going for HPSDRs is as follows:
		+	IP3=(3*(Input Level)-(IMD Level))/2
		+
		+	Where IP3 is the level where the desired response and the third-order IMD would theoretically be the same, if extended beyond their linear regions (In reality these levels would be a Mercury A/D overload level... positive dBm values). The values are considered a figure of merit.
		+
		+	The "Input Level" is the dBm value of the two signals of equal level that provides a given third order product level.
		+
		+	The "IMD Level" is a target level of -97 dBm for all HPSDR receiver designs.