Receive Performance Comparisons

 

 

K2 Product Reviews and Comments Links

 

 

Lab Receiver Test Data Comparisons

(ARRL QST Review Data, plus some data from Sherwood Engineering)

XX/YY =  (preamp-off) / (preamp-on); 14Mhz operation, 500 Hz CW filter, AGC off, High Ip mode.

All measurements in dB. Lab tests and rigs can vary by several dB, so results within 2-3 dB are roughly equivalent.

Numbers in RED indicate data that is 10 dB or more worse than for the K3. (A factor of ten signal power difference.) 

RIG 
MDS (dBm)

Sensitivity

pre off / on

BDR

'Desense'

 5 kHz spacing

pre-amp  off

BDR 

'Desense'

 20 kHz spacing 

pre off / on

IMD DR3 

'Intermod'

5 kHz spacing

pre-amp off

IMD DR3
 

'Intermod'

20 kHz spacing

pre off / on

 Ip3 (dBm)

20 kHz spacing 

5 kHz spacing  

pre off / on

Ip2 (dBm)

Out of band Signal Rejection  pre off / on

Phase Noise (dBc at +4 kHz) Receive Current

(Also see below)

K3 (ARRL)

K3  (Sherwood Eng.)

-130/-137

-130/-138

139 (2 kHz)

139/134

140 (100 kHz)

102 (2 kHz)

101 (2 kHz)

103/99

104

+26/+14

+26 (2 kHz)

+79/+79

-133 (4 kHz)

-139 (10 kHz)

800 mA

K2 

-130/-136

 135

  

134 / 126

 91

97 / 95

+21/+8  (20kHz)

+21/+8 (5kHz)

+80 / +79

 -124 150-200 mA
Ten-Tec Orion II -127/-137 136 136/134 96 92/90

+20/+6 (20kHz)

+20 (5 kHz pre off)

+82/+80 -138 3.6A
FTdx9000D -122/-134 127 138/137 95 99/99 +27/+15 (20kHz)

+20/+10 (5 kHz)

+64/+66 -120 110 V Supply

IC-7800

See Note 2

-127/-138/-142 115 137/138/135 89 104/103/102 +37/+21/+11  (20kHz)

+22/+7.7/+0.5 (5 kHz)

+98/+87/+84 -120

110 V Supply

Ten-Tec Omni6+

See Note 1

-133

 119

123 (nl)

 86

97

+12  (20kHz)

+58

 -117 2A
Ten-Tec OMNI VII -130/-140 135 137/134 84 91/91

+11/-0.5

+6.5 (5 kHz)

+73/+75 -110 2.2A

FT-1000MP

-128  /-135

119

142 / 137

 83

97 / 94

+15 / +5  (20kHz)

+86/+88

 -118 2.8A

SDR-5000

  (Sherwood Eng.)

-123/-135

123

96 (2 kHz)

96

-123 (10 kHz)

SDR-3000 -121/-135 113 113 98 99/99 +26/+14

+22 (2 kHz)

+69/+45 -120 2.8A
IC-7600 -131/-139 113 122 94 (5 kHz)

88 (2 kHz)

106/102 +28/+12

+10 (5 kHz pre-off)

+63/+59 -118 2.4A
IC-756PRO III

See Note 2

-131/-139/-141 101 121/119/113 77 103/100/99 +25/+14/+5  (20kHz)

-17/-29/-35 (5 kHz)

+73/+71/+68 -126 3.4A
IC-756PRO II

See Note 2

-131/-139/-141 100 118/116/107 76 97/95/91 +20.2/+10.2/-4.1  (20kHz) +75/+71/+59 -130 3.5A

IC-756PRO

See Note 2

-128 / -136 / -140

104

127 / 125 / 120

80

95 / 92 / 88

+15.4 / +4.3 / -6.9

+64 / +63 / +43

-130 3A
IC-746PRO

See Note 2

-132/-140/-142 100 125/123/118 75 97/96/92 +13.5/+3.7/-4 +72/70/+54 -123 1.9A

TS-870

-129 / -139

not tested

127 / 123

not tested

97 / 95

+16 / +4

+63 / +63

-118 2A

TS-930

See Note 1

-139 not tested noise limited not tested 86.5 -7.75 not tested not tested 110V supply

Ten Tec Argo V

Model 516

See Note 1

-132 67 118 62 85 -3.4 +47 -108 1A

Ten-Tec Jupiter

See Note 1

-135

not tested

123(nl)

not tested

85(nl)

+7.3

+53.6

-115 1.5A

Ten-Tec Scout

See Note 1

-125

 not tested

119

 not tested

87

+5.5

 not tested -95 600 mA

Ten Tec Pegasus

See Note 1

-132

not tested

110 (nl)

not tested

77

+7.2

+44.3

-104 1A

TS-50

-132/-139

 not tested

113 / 109

 not tested

90 / 88

+3 / -7

 not tested -115 800 mA
FT-100

See Note 3

 -133/-137 ~100 +130/+125 ~70 94/91 +10/+4.2 +51.7/+52.8 -118 1.5A

FT-817

-126/-134

not tested

106/104

not tested

87/84

+5/-5.6

+84/+88.4

-103 450 mA
FT-897 -133/-137 96 (nl) 109/106 67 89/86 -1.3/-6.7 +67/+62 -102 900 mA
IC-703 -131/-141 95 121(nl)/122(nl) 76 89/91 +11/+1.9 +56/+47 -118 320-580 mA

IC-706MKIIG

-136/-142

 86

122(nl) / 120(nl)

 74

89 / 86

-1.3 / -11

+36.4 / +38.5

-118 2A

Kachina 505DSP

-133 / -142

not tested

103 / 103

not tested

99 / 97

+15.5 / +3.5

+49 / +30

-117 2A

Note 1: Only one set of numbers is listed because these radios use a fixed gain front end which is not switchable. Compare their dynamic range and IP3 numbers to other rig's by using similar MDS figures to determine which set of numbers to use (pre-on / pre-off) for comparison.

Note 2:  The IC-7800, IC-756PRO & PROII  and IC-746PRO have two different gain preamps. Numbers are for Pre-Off / Pre #1 / Pre #2.  Pre #2 adds more RX gain than Pre #1 at the expense of  dynamic range. Higher preamp gain reduces strong signal dynamic range. For comparison, Pre-Off and Pre #1 most closely match the K2's and other radio's settings and are the most commonly used positions.

Note 3:  FT-100 5 kHz dynamic range numbers taken from swept dynamic range graphs in ARRL expanded test report.

ARRL Results are from QST rig reviews (K2, 2/04 (K2/100) and  3/00  (K2) reviews);  IC756 PRO, 6/00; Omni6+, 11/97; FT1000MP, 4/96; Scout, 12/93; TS-50, 9/93; SGC-2020, 10/98; IC706MKII, 7/99; Ten Tec Pegasus, 2/00; Ten Tec Jupiter, 6/01; TS-930, 1/84; Kachina 505DSP, 5/98; Patcom PC-1600A, 12/00; FT817, 4/01; FT-100, 6/99, Argo V 4/2003; FT-897, 5/2003; IC-703, 7/2003; Orion II 9/06; IC-7800, 8/04; 756PRO-III, 3/05; FTdx9000D,  8/05; SDR-3000, 10/09; IC-7600, 11/09). Sherwood Engineering results are from their receiver test results page. K3 (QST, 4/08) (Sherwood Engineering, 2/08); SDR-5000 (Sherwood Engineering, 2/08); OMNI VII, 7/2007

5 kHz Signal Spacing (ARRL Lab Results & Comments)

Rig Minimum Supply Voltage and Current Requirements

RIG  Min. RX Current Drain Min. Supply Voltage Notes

K2 

150 mA to 200 mA

9V Note 1A, 1B

FT-1000MP

2.8A

13.5 V  

IC-756 PRO*

3A 11.7 V  
IC-756 PRO II* 3.5A 11.7 V  

Ten-Tec Omni6+

2A 12.0 V  
Ten-Tec Orion 3.1A    

Ten Tec Argo V

Model 516

1A    
IC-703 320 mA to 580 mA    
FT-897 900 mA    

TS-870

2A 11.7V Note 3
TS-930 110 V supply 110 V supply  

Kachina 505DSP

2A unknown  

Pegasus 550DSP

1A 12V  

Ten-Tec Jupiter

1.5A 12 V  

Patcom PC-1600A

3.3A unknown Note 4

FT-817

450mA 8 V  
FT-100 1.6 A unknown  

IC-706MKIIG

2A 11.7 V  

TS-50

800mA 11.7 V Note 4

Ten-Tec Scout

600mA 12 V  

SGC-2020

430mA 10.5 V Note 2

Note 1A (K2 supply voltage): The table below shows the recommended maximum power output setting vs. supply voltage. Supply voltage was measured at K2 DC input jack in transmit mode. (The reverse-polarity protection diode, D10 on the K2 RF board, was a 95SQ015. This diode is supplied with all K2s with s/n 3000 or higher. Older K2s used an SB530 diode; add 0.3 V to the DC voltages in the table in this case. Upgrading to the 95SQ015 diode is recommended for use at low  supply voltages.)

DC VOLTAGE  POWER OUTPUT
9.0 V 2.0 W
9.5 V  5.0 W
10.0 V  7.0 W
10.5 V  10.0 W

Note 1B (K2 current drain): 0.15-A minimum receive current is with receiver in OPT BATT (battery save) mode. In OPT PERF (performance) mode, minimum receiver current is approx. 0.2 A. All K2 receiver performance measurements were made using OPT PERF mode (see "ARRL Lab Receiver Test Data Comparisons" table, above).

Note 2 (SG2020): Different user's manual editions claim 11 V or 9 V minimum. SGC tech support says the 9 V claim is incorrect, and that the actual minimum is
10.5 V. This is consistent with the LM2940-10 voltage regulator used. Max power output at reduced voltages not specified.

Note 3 (TS870): Standby current drain shown. Active current drain not specified.

Note 4 (Patcomm, TS-50): Current drain not specified. Used ARRL test data.

Definitions of Receiver Comparison Test Results 

 

nl = test was noise limited (noise floor rose 1db before 1db of blocking desense occurred)

MDS = Minimum Discernible Signal (3db increase above noise floor). Larger negative numbers are generally better, but too much sensitivity can reduce strong signal dynamic range and Ip3. Pre-Amp On MDS numbers of -130 dBm or more are more than adequate for most HF band operating, since band noise is typically above this number. (Lower frequencies need less MDS (more +number) due to an increase in atmospheric noise.)

IMDDR3 = 2 tone (20 kHz spacing) 3rd order Two tone IMD Dynamic Range. This test shows how the RX performs in the presence of multiple strong nearby signals in relation to its sensitivity (MDS). Higher is better. Pre-Amp Off  IMDDR3 numbers of +95dB (20 kHz spacing) and +90 dB (5 kHz spacing) or more are considered good. 

Ip3 = 2 tone (20 kHz spacing) 3rd order Intercept Point. This test also shows how the RX performs in the presence of multiple strong nearby signals. Higher is better. Pre-Amp OFF IP3 numbers of +15dBm are good, and +20dBm or more is excellent. Note: Low RX sensitivity artificially increases the measured Ip3.

Ip2 = 2 tone (8.020MHz, 6.000MHz) 2nd order Intercept Point This test shows how the RX performs in the presence of multiple strong out of band signals (such as broadcast signals on 6Mhz and 8Mhz creating birdies at 14Mhz). Higher is better. A Pre-Amp OFF IP2 of +55dBm is OK, and +70dBm or more is considered excellent.

BDR = Blocking Dynamic Range  (20 kHz spacing). This test shows when the receiver's sensitivity begins to drop in the presence of strong near by signals. (Desense). A Pre-Amp OFF BDR (20 kHz signal spacing) of greater than 120dB is good. Greater than 130dB is considered excellent. BDR decreases on most multi-conversion receivers as the interfering signal spacing from the receiver's listening frequency is reduced. Single conversion receivers like the K2 typically do not see as much of a BDR degradation as interfering signal spacing is reduced.

Phase Noise = value read from ARRL test graph at  +10 kHz from the carrier. Numbers are for the worst case band. Larger negative numbers are better. Bad phase noise contributes to poor RX Blocking Dynamic Range (desense from nearby signals) and broadband TX noise. Good values are  -130 dBc or better at +10 kHz. See the actual ARRL phase noise plots in each review for details of other spurious phase noise components.