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Quasonix Compact RDMS Installation And Operation Manual Download Page 58

 

Compact RDMS

TM

 Telemetry Receiver

 

44

 

Quasonix, Inc. 

 

 

Figure 18: "Clean" Eye Pattern 

 

13.5  Know Your Transmitter 

If you know the brand and type of transmitter, these tips can help determine when to use PNC. 

If your transmitter was manufactured by these companies, PNC should be OFF: 

 

Quasonix – guaranteed 

 

Nova Engineering – highly likely 

 

L3 – probably, but digital transmitters only 

If the transmitter was manufactured by the companies below, PNC should be ON: 

 

Microwave Innovations 

 

Emhiser 

 

Southern California Microwave 

 

L3 (analog transmitters) 

 

 

 

 

 

 

Summary of Contents for Compact RDMS

Page 1: ...reproduced for distribution without prior written approval from Quasonix Inc Copyright Quasonix Inc All Rights Reserved Installation and Operation Manual Compact RDMSTM Telemetry Receiver Quasonix Inc 6025 Schumacher Park Dr West Chester OH 45069 06 November 2014 Revision 2 1 2 ...

Page 2: ...OQPSK TG and Tier II Multi h CPM Commands 7 5 Performance Specifications 20 5 1 DC Input 20 5 2 RF Frequency Error 20 5 3 Bit Error Rate 20 5 4 Synchronization 21 5 4 1 RF Input 23 6 IF Module 25 7 Maintenance Instructions 30 8 Product Warranty 31 9 Technical Support and RMA Requests 32 10 Appendix A Bit Error Rate Testing 33 11 Appendix B Pinouts for Optional 37 Pin Connector 37 12 Appendix C Det...

Page 3: ...ter Responses Wide Group Plotted on 100 MHz Span 27 Figure 11 Optional SAW Filter Responses for 70 kHz to 6 MHz 28 Figure 12 Optional SAW Filter Responses for 14 MHz and 28 MHz 29 Figure 13 Optional 37 Pin Numbers 37 Figure 14 Ideal PCM FM Phase Tree h 0 7 41 Figure 15 Phase Trajectory Never Forgets 42 Figure 16 Trellis Detection Gain with Zero to Minimum Phase Noise 42 Figure 17 Trellis Detection...

Page 4: ...eceiver iii Quasonix Inc Table 10 Optional 37 Pin Assignments 37 Table 11 QPSK Factory Reset Values 45 Table 12 PCM FM Factory Reset Values 46 Table 13 SOQPSK Factory Reset Values 47 Table 14 Multi h CPM Factory Reset Values 48 ...

Page 5: ...e need for any outboard bit synchronizer The RDMS is manufactured by Quasonix Inc 6025 Schumacher Park Drive West Chester OH 45069 CAGE code 3CJA9 1 2 Nomenclature The RDMS is available in a number of variations depending on the options specified at the time of order The features and modes installed in each unit are identified in the model number as depicted in Figure 1 Q Compact RDMS Part Numberi...

Page 6: ...5 VDC 35 VDC For example a model QSX RDMS 1 A15 Q0 1110 00 EQ is configured as follows Table 1 Model Configuration Example Identifiers Description QSX Quasonix product R Receiver Demodulator Bit Synchronizer DMS Demodulator Bit Synchronizer 1 Channels A15 15 pin MDM Male TTL Outputs Q Frequency band code 0 No Extended Tuning 1110 Tier 0 present Tier I present Tier II present Legacy PSK absent 00 P...

Page 7: ...and arrive at the receiving antenna with different time delays carrier phases and relative strengths The sum of these multiple transmission paths can produce serious distortion and signal fading resulting in poor data quality and long periods of data outage Contrary to most situations increasing the transmit power will not improve the link quality and may actually make the situation worse Narrowin...

Page 8: ...le decoder is used Each decoder is compatible with the convolutional encoding described in the Consultative Committee for Space Data Systems Recommendation for Space Data System Standards TM Synchronization and Channel Coding CCSDS 131 0 B 1 Blue Book September 2003 Section 3 1 2 2 8 Wide Voltage WV This option specifies a wide voltage operating range 15 VDC 35 VDC ...

Page 9: ...Band Configuration Codes P Lower L Upper L C 200 0 400 0 1150 0 1415 0 1435 5 1534 5 1585 0 1650 0 1750 0 1850 0 1855 0 4400 0 5150 0 5250 0 S 2185 0 2200 0 2394 5 2500 0 Base Base Base Base Base Extended Extended Extended Extended Extended Freq Code A C E F G H L M P Q R S U W X Y Z Legend Frequency Gap Standard Base Frequency Range Extended Frequency Range available by selecting Extended Tuning ...

Page 10: ...etry Receiver 1 Quasonix Inc 1 2 3 1 Additional Band Codes Two additional band codes are available Band Code 7 70 MHz standard range 0 5 MHz 20 MHz 70 MHz extended range Band Code T 2025 0 MHz to 2110 0 MHz standard range ...

Page 11: ...um LO phase noise measured at 70 MHz IF output 115 dBc Hz 1 MHz offset Maximum RF input 20 dBm 10 dBm for C band Available gain to 70 MHz IF output 114 dB Gain control 128 dB control range User selectable AGC or MGC AGC freeze AGC time constant Adjustable 0 1 ms to 1000 ms First IF bandwidth 60 MHz nominal IF rejection 90 dB Image rejection 70 dB RF input impedance 50 ohms Second IF Section IF fre...

Page 12: ...s Tier II 7 0 dB Eb N0 RF Input dBm 117 0 1 Mbps 107 0 10 Mbps Sensitivity BER 1e 5 Tier 0 8 6 dB Eb N0 RF Input dBm 101 4 1 Mbps 91 4 10 Mbps Tier I 11 2 dB Eb N0 RF Input dBm 98 8 1 Mbps 88 8 10 Mbps Tier II 13 0 dB Eb N0 RF Input dBm 97 0 1 Mbps 87 0 10 Mbps Bit Synchronizer Section Input codes NRZ L M S BIФ L M S Output codes NRZ L M S BIФ L M S Data and clock out TTL or RS 422 Lock detector o...

Page 13: ...Receiver 4 Quasonix Inc 3 Installation Instructions 3 1 Mechanical The Compact RDMS is designed to be mounted by eight 8 6 32 screws through the holes along the front and back edges as depicted in Figure 2 on the following page ...

Page 14: ...Compact RDMSTM Telemetry Receiver 5 Quasonix Inc Figure 2 RDMS in 4 00 x 3 00 x 1 00 Compact Housing ...

Page 15: ... an IF output Note that first generation hardware did not include the IF output The pin numbering and wiring for the MDM 15 male connector is shown in Figure 3 Refer to Appendix B for optional 37 pin information Figure 3 MDM 15 Pin Numbers Table 3 MDM 15 Pin Assignments Position Signal Description 1 28 VDC Primary 28 VDC power to module 2 Ground Primary power return 2 amps maximum Internally tied ...

Page 16: ...g this pin is equivalent to power cycling the module 12 Clock Return Ground for LVTTL outputs Clock for RS 422 outputs 13 Data Return Ground for LVTTL outputs Data for RS 422 outputs 14 Ones Detect LVTTL signal use for sync time testing 15 RS 232 Rx Input RS 232 commands from host controller By default the output data is valid on the falling edge of the clock as shown in Figure 4 The polarity of t...

Page 17: ...ses The IF is resistively coupled from the input of the demodulator Therefore the signal level on the IF output should be within 2 dB of the demodulator s input The IF output must have a 50 ohm load at all times Therefore if it is not connected to external test equipment then the 50 ohm terminator that comes installed on the port must remain attached ...

Page 18: ...eters are typically stored in binary format That is 1 designates the feature is enabled 0 designates the feature is disabled Table 5 Stored Parameters Parameter Name Description Default Value Bit Rate 24 kbps 40 Mbps depending on mode 1 Mbps Clock Polarity 1 or 0 denoting clock polarity inverted or not respectively 0 inversion OFF Data Polarity 1 or 0 denoting data polarity inverted or not respect...

Page 19: ...d adjust to Modulation Indices not at ideal 0 7 A Auto Tracking Note If the user cannot guarantee that the transmit source is a new generation digitally synthesized transmitter the receiver should be left in Tracking mode Failure to do so will cause the receiver to fail to acquire improperly deviated signals altogether All tracking loops are already optimized for fastest synchronization and should...

Page 20: ...cher Park Drive West Chester Oh 45069 513 942 1287 www Quasonix com http www Quasonix com CAGE CODE 3CJA9 FPGA Revision 0x3132 0x0000 PSK FW Revision 2 0 043 7 29 2008 PSK Figure 5 RDMS Welcome Message All commands are one or two alphabetic characters followed by 0 1 or 2 arguments If the command is issued with arguments there must be a space after the alphabetic characters The commands are not ca...

Page 21: ...stalled returns an Option Not Installed message Table 6 Standard and Optional User Commands Mnemonic Name Description Option s Required Basic or Advanced Command Mode Restriction Help Message Displays abbreviated list of available commands Standard Basic None AD Downconvert Antenna AD Report the downconvert antenna state AD 0 Set downconvert antenna state to OFF Disabled AD 1 Set downconvert anten...

Page 22: ...Rate Testing Standard Advanced Command None BL Break Lock Breaks false locks No additional parameters Standard Basic PSK legacy BM Bit Rate Measurement Report bit rate measurement Standard Basic PSK legacy BR Bit Rate Report or set baseband bit rate Examples BR Report the bit rate setting BR 5 Set bit rate to 5 Mbps BR 0 6 Set bit rate to 600 Kbps Standard Basic For Asynch PSK legacy modes BR A an...

Page 23: ...e differential decoding setting DE 0 Set differential decoding OFF DE 1 Set differential decoding ON Standard Basic SOQPSK DP Data Polarity Report or set data polarity inversion state Examples DP Display the current data polarity DP 0 Set data polarity to NOT inverted OFF DP 1 Set data polarity to inverted ON Standard Basic For Asynch PSK legacy modes DP A and DP B must be specified separately FL ...

Page 24: ... FS A Set IF filter to automatic FS 0 7 Manually set IF filter not recommended Standard 14 option permits 7 additional filters Basic None GO Start Restart Apply changes then reset demodulator Initiate demodulation with current parameters This command is required when setting both the modulation and the bit rate GO command is issued any time the bit rate is changed This forces the demodulator to re...

Page 25: ...rrent decoder state LD 1 Enable the LDPC decoder LD 0 Disable the LDPC decoder LD Advanced Command PSK legacy Select mode 7 OQPSK LP Lock Output Polarity Report or set the active level of the lock indication to active high or active low Examples LP Show the current lock output polarity LP 1 Set the active level to high LP 0 Set the active level to low Standard Advanced Command None MA Modulations ...

Page 26: ...e Examples MI Report Mod Index Track Status MI O Disable Mod Index Tracking Set to h 0 7 MI A Acquire mode enable MI A D Sets the maximum delta h indicates a change in h defaults to 0 005 MI A S Sets the delta h settling time defaults to 500 ms MI H Hold Mod Index Tracking at current position MI I Sets Trellis Index MI T Tracking mode enable MI T H x Sets the Tracking Hold threshold Standard Basic...

Page 27: ...Multi h CPM MO 3 Set modulation to BPSK MO 4 Set modulation to QPSK MO 5 Set modulation to AQPSK MO 6 Set modulation to AUQPSK MO 7 Set modulation to OQPSK MO 8 Set modulation to UQPSK MO 9 Set modulation to Digital PM DPM Standard Basic Limited to modes installed NZ NRZ Encoding Report or set the non return to zero NRZ value used by the receiver Examples NZ Show the current NRZ value NZ L Set the...

Page 28: ...et the operation of clock and data output muting clock and data outputs can be disabled after some period of time without lock Examples OM Show the output muting state OM 0 Disables output muting OM 1 Enables output muting OM T x Sets the delay between loss of lock and muted outputs in milliseconds from 0 to 46016 Standard Advanced Command None PA Reset Stored Configuration Resets ALL parameters i...

Page 29: ... the receiver the signal level into the demod the digitally scaled signal level the SNR and eb N0 Standard Advanced Command None PN Phase Noise Compensation Report or set phase noise compensation state Examples PN Report the phase noise compensation state PN 0 Set phase noise compensation to OFF PN 1 Set phase noise compensation to ON Standard Basic PCM FM PR Reset Defaults for Currently Selected ...

Page 30: ...ate Examples RN Report the derandomizer state RN 0 Set the derandomizer OFF RN 1 Set the derandomizer ON Standard Basic None SN Show Serial Number Report the serial number for the unit Standard Basic None SV Save Parameters Saves the current parameters in non volatile memory including frequency modulation bit rate data polarity clock polarity AGC state verbosity level etc Standard Basic None ...

Page 31: ...SY Displays current status report settings SY 5 Sets status output period to 5 milliseconds SY 5 100 Sets status header output once every 100 status updates The SY command reports system status information about the timing and frequency tracking loops as well as mod scaling lock indication and eb n0 data This command is very effective for troubleshooting link issues Standard Advanced Command Avail...

Page 32: ...nd PCM FM TO T Tape Output Source Sets the test output to a Tape source Enables or Disables the pre detection complex baseband as the tape output source When enabled T 1 pre detection complex baseband is selected as the source of data to send on I and Q analog outputs When disabled T 0 the I and Q analog outputs frequency phase information are restored to their normal defaults which vary by mode E...

Page 33: ...t verbosity level on a scale of 0 9 Examples VL Report the verbosity level VL 0 Set the verbosity level to 0 VL 5 Set the verbosity level to 5 Standard Advanced Command None ZZ Show Options Displays the current hardware configuration and options on the receiver Standard Advanced Command None Note regarding VF command The VF command sets the observation window for the Viterbi decoder in the trellis...

Page 34: ... of acquiring a signal with a frequency error of up to 100 kHz 5 3 Bit Error Rate The RDMS meets the following BER limits when tested with a signal source which complies with IRIG 106 05 Table 7 RDMS BER Specifications Maximum Eb N0 dB BER PCM FM Tier 0 SOQPSK TG Tier I Multi h CPM Tier II 10 3 7 5 9 5 11 0 10 4 9 0 11 5 12 5 10 5 10 0 13 0 13 5 10 6 11 0 14 5 14 5 Typical BER performance plotted ...

Page 35: ...X DMS 111 Tier I QSX DMS 111 Tier II QSX DMS 111 Figure 6 BER Performance for Tier 0 I and II 5 4 Synchronization The Compact RDMS offers very fast reliable acquisition even at very low signal to noise ratio Synchronization time is a function of modulation type and IF frequency error Typical SOQPSK results from 10 000 synchronization trials are shown in Figure 7 ...

Page 36: ...Compact RDMSTM Telemetry Receiver 22 Quasonix Inc Figure 7 Synchronization Time at Various Signal to Noise Ratios ...

Page 37: ...able 8 Band Configuration Codes P Lower L Upper L C 200 0 400 0 1150 0 1415 0 1435 5 1534 5 1585 0 1650 0 1750 0 1850 0 1855 0 4400 0 5150 0 5250 0 S 2185 0 2200 0 2394 5 2500 0 Base Base Base Base Base Extended Extended Extended Extended Extended Freq Code A C E F G H L M P Q R S U W X Y Z Legend Frequency Gap Standard Base Frequency Range Extended Frequency Range available by selecting Extended ...

Page 38: ...etry Receiver 24 Quasonix Inc 5 4 1 1 Additional Band Codes Two additional band codes are available Band Code 7 70 MHz standard range 0 5 MHz 20 MHz 70 MHz extended range Band Code T 2025 0 MHz to 2110 0 MHz standard range ...

Page 39: ...onses of the eight filters are shown in Figure 9 and Figure 10 note the change of horizontal scale between the two figures Six additional filters are available allowing for a total of 14 The optional filters are 70 kHz 1 4 MHz 3 MHz 6 MHz 14 MHz and 28 MHz The measured responses of the optional filters are shown in Figure 11 and Figure 12 Contact Quasonix for information about the optional filters...

Page 40: ...Compact RDMSTM Telemetry Receiver 26 Quasonix Inc Figure 9 70 MHz IF Module in 2 x 3 Chassis SAW Filter Responses Narrow Group 10 MHz Span ...

Page 41: ...Compact RDMSTM Telemetry Receiver 27 Quasonix Inc Figure 10 SAW Filter Responses Wide Group Plotted on 100 MHz Span ...

Page 42: ...Compact RDMSTM Telemetry Receiver 28 Quasonix Inc Figure 11 Optional SAW Filter Responses for 70 kHz to 6 MHz ...

Page 43: ...Compact RDMSTM Telemetry Receiver 29 Quasonix Inc Figure 12 Optional SAW Filter Responses for 14 MHz and 28 MHz ...

Page 44: ... Receiver 30 Quasonix Inc 7 Maintenance Instructions The Compact RDMS requires no regular maintenance and there are no user serviceable parts inside Please consult the factory for any maintenance upgrade or repair requirements ...

Page 45: ...Compact RDMSTM Telemetry Receiver 31 Quasonix Inc 8 Product Warranty The Compact RDMS carries a standard parts and labor warranty of one 1 year from the date of delivery ...

Page 46: ...horized return shipments must be addressed in the following manner Quasonix Inc ATTN Repair RMA 6025 Schumacher Park Drive West Chester OH 45069 To ensure that your shipment is processed most efficiently please include the following information with your product return Ship To Company name address zip code and internal mail drop if applicable Attention Contact person Name Title Department Phone nu...

Page 47: ...mmands BE c Bit Error Rate Status Report bit error rate status c is optional and indicates channel 0 or 1 If channel is omitted the current tracking channel TC is used If TC is 2 a channel number is required Examples BE Show the bit error rate status BE 1 Show the status of channel 1 BE D Bit Error Rate Status Continuous Report a continuous display of bit error rate status Examples BE D 0 Show con...

Page 48: ...tted the current tracking channel TC is used If TC is 2 a channel number is required T indicates type where n is one of the following C continuous clears limits T x time limit where x is between 0 and 4 29497E 06 seconds B x bit limit where x is between 0 and 9 3825E 13 E x error limit where x is between 0 and 3 1275E 13 BE G n Set Bit Error Measurement Gating Sets bit error measurement gating The...

Page 49: ...egister status c is optional and indicates channel 0 or 1 If channel is omitted the current tracking channel TC is used If TC is 2 a channel number is required Example BE 1 R Report bit register state for channel 1 BE c W reg value Set Hardware Bit Error Register Sets hardware bit error register reg to value c is optional and indicates channel 0 or 1 If channel is omitted the current tracking chan...

Page 50: ...g in the first three columns The following shows an example display with a five 5 second repeating test E R Time Bit Count Error Count Error Rate 0 00 00 03 772 3 773e 07 2 5 301e 08 0 00 00 04 023 4 023e 07 2 4 971e 08 0 00 00 04 276 4 276e 07 2 4 677e 08 0 00 00 04 527 4 528e 07 2 4 417e 08 0 00 00 04 779 4 780e 07 2 4 184e 08 0 00 00 05 000 5 000e 07 2 4 000e 08 0 00 00 00 251 2 512e 06 0 0 000...

Page 51: ...A Analog output 5VDC 2 DAC B Analog output 5VDC 3 RSSI Received Signal Strength Indication 0 3 3VDC 4 Data C Clock and Data pairs 5 DNC Factory use only Do Not Connect 6 DNC Factory use only Do Not Connect 7 28 VDC In System power 8 Ground System power 9 Ground System power 10 Clock A Clock and Data pairs 11 Data A Clock and Data pairs 12 Serial Ground RS232 Serial Connection Ground 13 Lock Detect...

Page 52: ...t Connect 25 SDI Signal Degradation Indication RF Networks 2241 26 28 VDC In System power 27 Ground System power 28 Power on Reset 29 Clock A Clock and Data pairs 30 Data A Clock and Data pairs 31 Ones Detect LVTTL Indicator Line 32 Serial RXD RS232 Serial Connection Received 33 Clock C Clock and Data pairs 34 Clock B Clock and Data pairs 35 Data B Clock and Data pairs 36 DNC Factory use only Do N...

Page 53: ...he state settings use the alpha O not a number zero 0 Mnemonic Name Description OC Help Message Displays abbreviated list of available commands OC Current Settings This is an example current settings will vary O_0 CLK_I0 O_1 DATA_I0 O_2 CLK_Q0 O_3 DATA_Q0 O_4 CLK_I1 O_5 DATA_I1 O_6 CLK_Q1 O_7 DATA_Q1 OC D Set Default Outputs O_0 CLK_I0 O_1 DATA_I0 O_2 CLK_Q0 O_3 DATA_Q0 O_4 CLK_I1 O_5 DATA_I1 O_6 ...

Page 54: ...before the changed parameter For example changing the secondary Clock and Data to match the primary commands are OC O_2 CLK_I0 OC O_3 DATA_I0 When the changes are made the list displays as follows OC O_0 CLK_I0 O_1 DATA_I0 O_2 CLK_I0 O_3 DATA_I0 O_4 CLK_I1 O_5 DATA_I1 O_6 CLK_Q1 O_7 DATA_Q1 Now the user has the clock and data I0 the letter I and the number 0 on both the primary A channel and secon...

Page 55: ...ow nominal data 0 Makes no use of adjacent symbols for error correction Trellis Detection Uses the phase tree for data detection Uses adjacent symbols to help decide on iffy bits Improves BER performance by 3 5 to 5 0 dB The Phase Tree shown in Figure 14 shows all of the possible paths the phase trajectory can take over a period of seven bits Figure 15 shows the two unique paths based on whether t...

Page 56: ...r decisions about each individual bit This process improves BER performance by about 3 5 to 5 dB over conventional FM detection However this assumes that the transmitter is really following the known and correct phase tree and this assumption is NOT always true High phase noise can reduce the trellis detection gain because phase noise corrupts the tree The following figures illustrate the differen...

Page 57: ...ock rate or have clock stability issues especially under harsh vibration conditions While the RDMS is capable of tracking static clock rate errors as large as 1000 ppM excessive jitter causes the integrated bit sync to lose lock Enabling the PNC mode opens the tracking loop bandwidth to accommodate for these issues This increase in bandwidth does have a tradeoff A wider tracking range allows the R...

Page 58: ...s can help determine when to use PNC If your transmitter was manufactured by these companies PNC should be OFF Quasonix guaranteed Nova Engineering highly likely L3 probably but digital transmitters only If the transmitter was manufactured by the companies below PNC should be ON Microwave Innovations Emhiser Southern California Microwave L3 analog transmitters ...

Page 59: ...set values for each mode are listed in the following tables Table 11 QPSK Factory Reset Values Parameter Reset State Bit Rate 1 Modulation Scaling N A Clock Polarity Normal Data Polarity Normal Derandomizer Disabled Differential Decoder N A IF Filter Auto Downconvert Antenna Disabled AGC Enabled Convolutional Decoder Disabled Lock Output Polarity Active High NRZ Encoding NRZ L Output Control Defau...

Page 60: ... Tracking Clock Polarity Normal Data Polarity Normal Derandomizer Disabled Differential Decoder N A IF Filter Auto Downconvert Antenna Disabled AGC Enabled Convolutional Decoder Disabled Lock Output Polarity Active High NRZ Encoding NRZ L Output Control Default Output Muting Disabled Phase Noise Compensation Disabled Tape Output Disabled ...

Page 61: ...ling N A Clock Polarity Normal Data Polarity Normal Derandomizer Disabled Differential Decoder Enabled IF Filter Auto Downconvert Antenna Disabled AGC Enabled Convolutional Decoder N A Lock Output Polarity Active High NRZ Encoding N A Output Control Default Output Muting Disabled Phase Noise Compensation Disabled Tape Output Disabled ...

Page 62: ...n Scaling N A Clock Polarity Normal Data Polarity Normal Derandomizer Disabled Differential Decoder N A IF Filter Auto Downconvert Antenna Disabled AGC Enabled Convolutional Decoder N A Lock Output Polarity Active High NRZ Encoding N A Output Control Default Output Muting Disabled Phase Noise Compensation Disabled Tape Output Disabled ...

Page 63: ...Disk CPM Continuous Phase Modulation DB 9 D subminiature 9 pin Serial Connector DC Diversity Combiner DHCP Dynamic Host Configuration Protocol DPM Digital Phase Modulation FPGA Field Programmable Gate Array IF Intermediate Frequency IP Internet Protocol kbps Kilobits per second KHz Kilohertz LCD Liquid Crystal Display Mbps Megabits per second MCX Snap on subminiature connector MHCPM multi h Contin...

Page 64: ...S 232 Recommended Standard 232 Serial Communications SAW Surface Acoustic Wave SDI System Degradation Indication SOQPSK Shaped Offset Quadrature Phase Shift Keying SOQPSK TG Shaped Offset Quadrature Phase Shift Keying Telemetry Group TRL Tracking Loop TTL Transistor Transistor Logic UDP User Datagram Protocol UQPSK Unbalanced Quadrature Phase Shift Keying USB Universal Serial Bus VAC Voltage Alter...

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