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− | == A Termination Insensitive Amplifier for Bidirectional Transceivers ==
| + | [[file:AudioAmp380-Mechs_Rev2.png]] |
| | | |
− | === Through Hole Version === | + | == Parts List == |
| | | |
− | [[file:TIA_P1015_720px.jpg]]
| + | {| class="wikitable" |
− | | + | ! Qty |
− | === Surface Mount Version === | + | ! Value |
− | | + | ! RefDes |
− | [[file:W7Z01_TIA_SMT_P1837-720PX.jpg]]
| + | ! |
− | | + | ! Qty |
− | == W7ZOI Design ==
| + | ! Value |
− | | + | ! RefDes |
− | * Paper - [http://w7zoi.net/bidirectional_matched_amplifier.pdf A Termination Insensitive Amplifier for Bidirectional Transceivers] - W7ZOI (Wes Hayward) design
| + | |- |
− | * [http://w7zoi.net/transistor_models_and_the_fba.pdf Transistor Models and the Feedback Amplifier]
| + | | 3 |
− | * Termination Insensitive - input impedance that does not depend upon the output load
| + | | Cap, 100nF |
− | * Bi-directional - amplifiers in both directions
| + | | C1,C3,C8 |
− | * 50 ohms in/out
| + | | |
− | * BNC or SMA Connectors
| + | | 1 |
− | * Transformer-less
| + | | IC, [https://www.mouser.com/ProductDetail/Texas-Instruments/LM380N-NOPB?qs=QbsRYf82W3FZTPVTV5PPcQ%3D%3D LM380N] |
− | * Power applied to one half at a time - determines signal flow direction
| + | | U2 |
− | * ~30 mA per side
| + | |- |
− | * SMT or Through Hole versions
| + | | 2 |
− | ** SMT version fits in 80x50x20mm aluminum case
| + | | Cap, 10uF |
− | | + | | C2,C6 |
− | === W7ZOI Schematic ===
| + | | |
− | | + | | 1 |
− | [[FILE:W7ZOI_SCHEMATIC.PNG]] | + | | IC, [https://www.mouser.com/c/semiconductors/amplifier-ics/operational-amplifiers-op-amps/?q=NE5534&mounting%20style=Through%20Hole&instock=y NE5534] |
− | | + | | U1 |
− | === * Use ===
| + | |- |
− | | + | | 1 |
− | * Between RF/LO mixer (IF output/input) and crystal filter
| + | | Cap, 470uF |
− | * Between Crystal Filter and Product Detector / Balanced Modulator
| + | | C4 |
− | | + | | |
− | [[file:FARHADPNG.PNG]]
| + | | 1 |
− | | + | | Res, Trimmer, 500 |
− | == Schematic in KiCAD ==
| + | | RV2 |
− | | + | |- |
− | * [http://land-boards.com/W7ZOI_TIA/W7ZOI_TIA_SCHEMATIC_REV1.pdf Schematic] (pdf file)
| + | | 2 |
− | * Single channel
| + | | Cap, 100uF |
− | * With SPICE directives
| + | | C5,C9 |
− | | + | | |
− | [[file:W7ZOI_SCHEMATIC_KiCAD.PNG]]
| + | | 1 |
− | | + | | Res, POT, 10K |
− | * Both channels
| + | | RV1 |
− | * With SPICE directives
| + | |- |
− | | + | | 1 |
− | [[file:W7ZOI_SCHEMATIC_KiCAD-2.PNG]]
| + | | Cap, 0.47uF |
− | | + | | C7 |
− | == NGSPICE Simulation ==
| + | | |
− | | + | | 1 |
− | * NGSPICE run from KiCAD
| + | | Jack, DCJ0202 |
− | ** [http://ngspice.sourceforge.net/ngspice-eeschema.html Tutorial: ngspice simulation in KiCad/Eeschema]
| + | | J3 |
− | * +24 dB @12V
| + | |- |
− | * 2N3904 Alternate Node Sequence (MMBT3903 - SOT23)
| + | | 1 |
− | ** KiCAD order 1 2 3 is the SPICE normal order
| + | | Res, 51, 1/4W |
− | ** NGSPICE order: 3 1 2
| + | | R1 |
− | | + | | |
− | [[file:W7ZOI_Simulation_KiCAD-3.PNG]]
| + | | 2 |
− | | + | | Jack, RCA |
− | * Closely matches
| + | | J1,J2 |
− | | + | |- |
− | [[file:W7ZOI_Gainz.PNG]]
| + | | 1 |
− | | + | | Res, 10, 1/4W |
− | * Across Band
| + | | R2 |
− | [[file:W7ZOI_Simulation_KiCAD_S2.PNG]]
| + | | |
− | | + | | |
− | == Measurements ==
| + | | |
− | | + | | |
− | * Powering only L-R side
| + | |- |
− | * 30 mA power supply current
| + | | 2 |
− | * 12V
| + | | Res, 10K, 1/4W |
− | | + | | R3,R4 |
− | === NanoVNA Measurements (Through-hole) === | + | | |
− | | + | | |
− | ==== Left-to-right flow ====
| + | | |
− | | + | | |
− | * At 9 MHz
| + | |- |
− | | + | | 1 |
− | [[file:L-R_1-30MHz_meas.png]]
| + | | Res, 2.7, 1/4W |
− | | + | | R5 |
− | * S21 - sweep 1-30 MHz
| + | | |
− | | + | | |
− | [[file:L-R_1-30MHz_S21.png]]
| + | | |
− | | + | | |
− | * S11 VSWR - sweep 1-30 MHz
| + | |- |
− | | + | |} |
− | [[file:L-R_1-30MHz_S11.png]]
| |
− | | |
− | ==== Right-to-Left flow ====
| |
− | | |
− | * At 9 MHz
| |
− | | |
− | [[file:R-L_1-30MHz_meas.png]]
| |
− | | |
− | * S21 - sweep 1-30 MHz
| |
− | | |
− | [[file:R-L__1-30MHz_S21.png]]
| |
− | | |
− | * S11 VSWR - sweep 1-30 MHz
| |
− | | |
− | [[file:R-L_1-30MHz_S11.png]]
| |
− | | |
− | === NanoVNA Measurements (SMT) ===
| |
− | | |
− | * Re = 150
| |
− | ** A bit more gain
| |
− | | |
− | ==== Left-to-right flow ====
| |
− | | |
− | * At 9 MHz
| |
− | | |
− | [[file:L-R_1-30MHz_meas_SMT.png]]
| |
− | | |
− | * S21 - sweep 1-30 MHz
| |
− | | |
− | [[file:L-R_1-30MHz_S21_SMT.png]]
| |
− | | |
− | * S11 VSWR - sweep 1-30 MHz
| |
− | | |
− | [[file:L-R_1-30MHz_S11_SMT.png]]
| |
− | | |
− | ==== Right-to-Left flow ====
| |
− | | |
− | * At 9 MHz
| |
− | | |
− | [[file:R-L_1-30MHz_meas_SMT.png]]
| |
− | | |
− | * S21 - sweep 1-30 MHz
| |
− | | |
− | [[file:R-L__1-30MHz_S21_SMT.png]]
| |
− | | |
− | * S11 VSWR - sweep 1-30 MHz
| |
− | | |
− | [[file:R-L_1-30MHz_S11_SMT.png]]
| |
− | | |
− | == CAD ==
| |
− | | |
− | === Through Hole CAD ===
| |
− | | |
− | * 2.4" x 2.4"
| |
− | * 2.0 hole center-to-center
| |
− | | |
− | [[FILE:W7ZOI_CAD.PNG]]
| |
− | | |
− | === SMT CAD ===
| |
− | | |
− | [[FILE:W7ZOI_TIA_SMT_CAD.PNG]]
| |
− | | |
− | == Test Procedure ==
| |
− | | |
− | === Test Equipment ===
| |
− | | |
− | * Unit Under Test (UUT)
| |
− | * [[NanoVNA]]
| |
− | * [[RF_Attenuators#Triple_Attenuator|30 dB attenuator]] tap on Triple attenuator
| |
− | * [[NanoVNA#RF_Demo_Kit|RF Demo Kit]]
| |
− | * (3) SMA to SMA Male:Male cables
| |
− | * [[Benchtop Power Supply DPS3005]]
| |
− | ** 12V Power Supply
| |
− | ** Current Limit set at 100 mA
| |
− | | |
− | === Calibrate NanoVNA ===
| |
− | | |
− | * Cable #1 from RF out of NanoVNA (upper jack) to left side of 30 dB attenuator
| |
− | * Cable #2 from right side of 30 dB attenuator to left side of RF Demo Kit
| |
− | ** Multiple positions for open, through, and short
| |
− | * Cable #3 from right side of RF Demo Kit to input of NanoVNA (lower jack)
| |
− | | |
− | === Test UUT ===
| |
− | | |
− | * Replace RF Demo Kit with UUT
| |
− | * Test each direction at a time
| |
− | ** Power up Left to right, test
| |
− | ** Power up right to left, test
| |
− | * Should show gain of about 20 dB at 10 MHz
| |
− | | |
− | == Enclosure ==
| |
− | | |
− | * The SMT version is designed to fit in a [https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2047675.m570.l1313&_nkw=80x50x20mm&_sacat=0 80x50x20mm Extruded Aluminum Project Box]
| |
− | * [http://land-boards.com/W7ZOI_TIA/W7ZOI_TIA_SMD_CUTOUTS.pdf W7ZOI_TIA_SMD_CUTOUTS.pdf Panel marking template]
| |
− | | |
− | [[file:Dimensions_80x50x20.jpg]]
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− | | |
− | == Videos ==
| |
− | | |
− | <video type="youtube">JjcxEYk9atg</video>
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− | | |
− | <video type="youtube">CpQK0W7TY5g</video>
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− | | |
− | <video type="youtube">7TtKE39TWpI</video>
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− | | |
− | <video type="youtube">T8lq8Qtjqe0</video>
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− | | |
− | == Assembly Sheet ==
| |
− | | |
− | * [[W7ZOI TIA Assembly Sheet - Rev 1]] - Through-hole version
| |
− | * [[W7ZOI TIA SMT Assembly Sheet - Rev 1]] - SMT version
| |