Difference between revisions of "Kits and Parts Mixers"

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== Kits and Parts Mixers Features in Common ==
+
[[file:K&P_ADE_Mixer-P1899-720px.jpg]]
  
* All Ports are 50Ω
+
== Kits and Parts Mixers - Features in Common ==
* +7dBm Local Oscillator Injection Design
+
 
* Full Diplexer at the IF Port
+
* Available as [https://kitsandparts.com/DBDM.php Diode Ring Mixer] or [https://kitsandparts.com/ADE.php ADE-1 || ADE-6 Double Balanced Diode Ring Mixer] kits from [https://kitsandparts.com/ Kits and Parts]
* Optional Attenuators for RF & LO Ports
+
* LO, IF, RF Ports are all 50Ω
 +
* +7dBm Local Oscillator injection level
 +
** As measured into 50Ω load
 +
*** Mixers are not linear and loads should not be measured at the mixer
 +
* ~5dB RF > IF conversion loss in HF region
 +
* IF Port
 +
** Full Diplexer at the IF Port
 +
** Low Pass Filter can be populated if used as Product Detector / Balanced Modulator
 +
* Board has pads (1206 SMT or 1/8W resistor pads) for optional Attenuators on RF & LO Ports
 +
* 3 pin, 0.1" pads at board edges allow SMA edge connectors to be used
 +
* Mounting holes in all 4 corners
  
 
== Kits and Parts ADE-1 Mixer ==
 
== Kits and Parts ADE-1 Mixer ==
  
 
* [https://kitsandparts.com/ADE.php Kits and Parts Mixer]
 
* [https://kitsandparts.com/ADE.php Kits and Parts Mixer]
* 7 MHz RF, 40 M band
+
* Mini-Circuits ADE-1+ Double Balanced Diode Mixer with built in 50Ω transformers
* 16 MHz LO
+
** [https://www.minicircuits.com/pdfs/ADE-1+.pdf ADE-1+ Datasheet]
** Si5351A square wave drive, 50 Ohm source impedance, 1.65V peak
+
* Not necessary to build and tune diplexer first if using [[NanoVNA]] and/or [[tinySA]]
* 9 MHz IF feeds Crystal Filter
+
** Only 1 cap adjust
** SSB or CW [[Crystal Filter Design|Crystal Filter Design]]
+
** Inductors can also be spread/compressed if needed
*** [[Crystal Filter Design#SSB 4 Crystal Filter on Kits and Parts Board|SSB4 Crystal filter]]
+
* Available from [https://kitsandparts.com/ADE.php Kits and Parts] as bare PCB or kit of parts
*** [[Crystal_Filter_Design#CW 5 Crystal Filter on Kits and Parts Board|CW5 Crystal Filter]]
+
** Bare board - $5
 +
** Kit - $14
 +
*** Good deal since the [https://www.mouser.com/ProductDetail/Mini-Circuits/ADE-1%2b?qs=xZ%2FP%252Ba9zWqZNkkNe3uAsRQ%3D%3D mixer itself is $6]
  
 
[[file:ADE-1.SCH.png]]
 
[[file:ADE-1.SCH.png]]
  
 
[[file:ADE-1.PCB.png]]
 
[[file:ADE-1.PCB.png]]
 +
 +
=== ADE-1 Schematic ===
 +
 +
[[file:ADE-1_Schematic.PNG]]
 +
 +
=== Performance ===
 +
 +
[[file:Chart_dBm-to-Volts.PNG]]
 +
 +
[[file:ADE-1_Performance.PNG]]
 +
 +
[[file:ADE-1_ElectricalSpecs.PNG]]
 +
 +
=== Port VWSR ===
 +
 +
* Measured VSWR of 2.23 at 9 MHz with NanoVNA matches spec nicely
 +
 +
[[file:ADE-1_LO_VSWR.PNG]]
 +
 +
[[file:ADE-1_IF_VSWR.PNG]]
 +
 +
[[file:ADE-1_RF_VSWR.PNG]]
 +
 +
=== ADE-1 Measurements ===
 +
 +
==== NanoVNA Measurements ====
 +
 +
* No RF in
 +
* LO driven by NanoVNA Tx
 +
** About -10dBm output
 +
* IF output to NanoVNA Rx
 +
* IF at 9 MHz
 +
** VSWR: 2.233
 +
** S21 Gain: -67 dB
 +
 +
[[file:ADE-1.NanoVNA_LO-to-IF.png]]
 +
 +
* NanoVNA
 +
* No LO in
 +
* RF driven by NanoVNA Tx
 +
* IF output to NanoVNA Rx
 +
* IF at 9 MHz
 +
** VSWR: 2.216
 +
** S21 Gain: -42 dB
 +
 +
[[file:ADE-1.NanoVNA_RF-to-IF.png]]
 +
 +
* Scanning from 1 to 100 MHz
 +
 +
[[file:ADE-1.NanoVNA_RF-to-IF_1-100MHz.png]]
 +
 +
==== tinySA Measurements ====
 +
 +
===== LO to IF port isolation =====
 +
 +
* Driven by [[VFO-001]] 3.3V squarewave output
 +
** Signal level about 0.5 dBm
 +
** CLK0 = 9 MHz into LO port
 +
* Monitor IF output from mixer on tinySA
 +
** Output through 20 dB attenuator (tinySA set to -20dB gain)
 +
 +
[[file:ADE-1.tinySA_RF-to-IF_9Mhz-center.png]]
 +
 +
===== Mixer Operation =====
 +
 +
* Mixer is driven by [[VFO-001]] 3.3V squarewave outputs
 +
** Signal output levels about 0.5 dBm
 +
** CLK0 = RF @7 MHz [[VFO-001]] output with 30 dB attenuator
 +
** CLK1 = LO @16 MHz no attenuator
 +
* Monitor IF output from mixer on [[tinySA]]
 +
** IF out to tinySA with 20 dB attenuator (tinySA set to -20dB gain)
 +
 +
[[file:ADE-1.tinySA_LO-16MHz_RF-7MHz-to-IF_9Mhz-center.png]]
 +
 +
* Same but 9 MHz picked out
 +
* Approx. 8 dB insertion loss
 +
 +
[[file:ADE-1.tinySA_LO-16MHz_RF-7MHz-to-IF_9Mhz-at9MHz.png]]
 +
 +
* Look at 7 MHz RF freq on IF output
 +
 +
[[file:ADE-1.tinySA_LO-16MHz_RF-7MHz-to-IF_9Mhz-at7MHz.png]]
 +
 +
* Look at 16 MHz LO freq on IF output
 +
 +
[[file:ADE-1.tinySA_LO-16MHz_RF-7MHz-to-IF_9Mhz-at16MHz.png]]
  
 
== Kits and Parts Diode Mixer ==
 
== Kits and Parts Diode Mixer ==
  
 
* [https://kitsandparts.com/DBDM.php Double Balanced Diode Ring Mixer Kit]
 
* [https://kitsandparts.com/DBDM.php Double Balanced Diode Ring Mixer Kit]
* All Ports are 50Ω
+
* Not necessary to build and tune diplexer first is using a [[NanoVNA]] or [[tinySA]] to adjust
* +7dBm Local Oscillator Injection Design
+
* Available from [https://kitsandparts.com/ADE.php Kits and Parts] as bare PCB or kit of parts
* Full Diplexer at the IF Port
+
** Bare board - $5
* Optional Attenuators for RF & LO Ports
+
** Kit - $12
 +
 
 +
=== Diode Mixer Card Schematic ===
  
 
[[file:DBDM.SCH.png]]
 
[[file:DBDM.SCH.png]]
Line 35: Line 135:
 
== Bridged Tee Diplexer ==
 
== Bridged Tee Diplexer ==
  
<blockquote>Diplexor is a bandpass/band-stop filter popularized by [https://www.youtube.com/watch?v=iVUv8C-8g-Y Joe Reisert W1JR] that is used after a double Balanced Mixer to provide a 50 ohm termination to all frequencies at the mixer's IF port, and to the following amplifier stage.  Maintaining a consistent load at the mixer avoids overload and Inter-Modulation Distortion (IMD) effects that these mixers are prone to when not properly terminated.</blockquote>
+
Diplexor is a bandpass/band-stop filter popularized by [https://www.youtube.com/watch?v=iVUv8C-8g-Y Joe Reisert W1JR] that is used after a double Balanced Mixer to provide a 50 ohm termination to all frequencies at the mixer's IF port, and to the following amplifier stage.  Maintaining a consistent load at the mixer avoids overload and Inter-Modulation Distortion (IMD) effects that these mixers are prone to when not properly terminated.
  
 +
=== LTSpice simulation ===
 +
 +
* 9 MHz
 +
* FT37-67, 20T-12" = 8 uH
 +
* T37-17, 13T-10" = 250 nH
 +
* C2 adjusts peak from left to right
 +
 +
[[FILE:DIPLEXER_SPICE_SIM.PNG]]
 +
 +
* [https://www.changpuak.ch/electronics/calc_16a.php Diplexer Calculator (Bridged Tee) Diplexer Calculator]
 
* [https://www.qsl.net/g3oou/mixerterminations.html Mixer Diplexer description]
 
* [https://www.qsl.net/g3oou/mixerterminations.html Mixer Diplexer description]
* [https://www.changpuak.ch/electronics/calc_16a.php Diplexer Calculator (Bridged Tee) Diplexer Calculator]
+
 
 +
[[file:Diplexer.PNG]]
 +
 
 +
[[file:Diplexer_pass.PNG]]
  
 
<video type="youtube">zOk_0IiIgZY</video>
 
<video type="youtube">zOk_0IiIgZY</video>
 +
 +
==== Toroid Winding Direction ====
 +
 +
* Toroids needs to be wound to match the pad locations/offsets on the PCB
 +
 +
[[file:toroid-cw.jpg]]
 +
 +
=== Adjust IF Diplexer C1 (ADE-1) ===
 +
 +
* Drive RF port from [[NanoVNA]]
 +
** Nominal 0 dBm drive level
 +
* IF port is output
 +
** Listen on IF port on [[NanoVNA]]
 +
* No drive on LO
 +
* 9 MHz is IF design frequency
 +
* Nano VNA set to scan from 1 Mhz to 30 MHz
 +
** Shows peak expected signal around 9 MHz
 +
 +
[[file:ADE-1.NanoVNA_RF-to-IF.png]]
 +
 +
* Scan from 8 to 10 MHz
 +
* Adjust C1 to peak near 9 MHz
 +
** Eliminate double peaks
 +
 +
[[file:ADE-1.NanoVNA_RF-to-IF_8-10MHz.png]]
 +
 +
== ADE-1 Mixer as Product Detector ==
 +
 +
[[FILE:P1927-720PX.jpg]]
 +
 +
* RF is 9 MHz from IF stage
 +
* LO is 9 MHz BFO from [[VFO-003]]
 +
** Minor adjustments to get to side of the base band offset
 +
* IF output is audio
 +
** Mixer goes down to DC
 +
* IF needs Audio Filter
 +
** IF port wants to see 50 Ohm termination across output
 +
** 0.33 uF cap/50 ohms terminates higher frequencies at 50 ohms
 +
** [https://www.mouser.com/ProductDetail/871-B78108S1155J 1.5 mH inductor] in series as filter on audio output
 +
* LTSpice Simulation
 +
 +
[[file:LP_Audio-2.PNG]]
 +
 +
* Circuit Mods
 +
 +
[[file:ADE-1_AF_Filter-2.PNG]]
 +
 +
* IF section
 +
 +
[[file:ADE-1_AF_Filter_Physicals-4.PNG]]
 +
 +
== Typical Application ==
 +
 +
* 7 MHz RF, 40 M band
 +
* 16 MHz LO
 +
** Si5351A square wave drive
 +
* 9 MHz (difference 16-7=9) IF feeds Crystal Filter
 +
** SSB or CW [[Crystal Filter Design|Crystal Filter Design]] - 9 MHz nominal
 +
*** [[Crystal Filter Design#SSB 4 Crystal Filter on Kits and Parts Board|SSB4 Crystal filter]]
 +
*** [[SSB6_Design|SSB6 Design Crystal filter]]
 +
*** [[Crystal_Filter_Design#CW 5 Crystal Filter on Kits and Parts Board|CW5 Crystal Filter]]
 +
* Use Si5351 to drive LO port
 +
** Drive pad attenuator may be required
 +
* Use Si5351 to drive RF port for testing
 +
** Use large external pad attenuator for low level signal insertion
 +
 +
[[FILE:MIXER_TEST.png]]
 +
 +
=== Si5351A Drive Level ===
 +
 +
* [https://www.skyworksinc.com/-/media/Skyworks/SL/documents/public/data-sheets/Si5351-B.pdf Si5351A] used to drive LO and/or RF ports
 +
** 3 outputs
 +
** LO at full level (+7dBm)
 +
** RF at various levels with attenuators to drop to expected RF signal levels
 +
* Don't want more than 7 dBm into LO or RF ports
 +
* Two Si5351 Designs to drive ADE-1 LO or RF ports
 +
** [[VFO-001]]
 +
*** Uses the Si5351 without external drivers
 +
*** Set drive levels to 2mA, 4mA, 6mA or 8mA
 +
** [[VFO-003]] - Adds 50Ω drivers
 +
*** Level is fixed
 +
*** Three 74AC14 parts with 150 ohms outputs paralleled
 +
*** 13 dBm output
 +
*** Install 6 dBm attenuator on board (13-6=7)
 +
 +
==== VFO-001 drive ====
 +
 +
* The RMS value is for square-wave voltages whose pulse duration (ti) and pause (tp) have the same length:
 +
 +
[[file:RMS-SquareWave.PNG]]
 +
 +
* [https://www.redcrab-software.com/en/Calculator/Electrics/Rectangular-Voltage-RMS-Value#:~:text=The%20rms%20value%20is%20for%20square-wave%20voltages%20whose,rms%20value%20is%20equal%20to%20the%20peak%20value Square Wave Calculator]
 +
 +
[[file:RMS-SquareWave-2.PNG]]
 +
 +
* Drive level of 3.3V
 +
 +
[[file:RMS-SquareWave-3.PNG]]
 +
 +
* 100 mW is 20 dBm
 +
* ADE-1 needs 7 dBm level
 +
* Would need a 13 dB attenuator
 +
** Not actually true
 +
*** Although the Si5351 datasheet says it drives 50 Ohms loads this is not exactly the case
 +
*** Drive levels are controlled by the output current setting
 +
* Si5351A outputs measured on [[VFO-001]]
 +
** Drive Level 2 mA = 0.2 dBm
 +
** Drive Level 4 mA = 6.2 dBm << Use this level
 +
** Drive Level 6 mA = 9.7 dBm
 +
** Drive Level 8 mA = 11.7 dBm
 +
 +
==== VFO-003 drive ====
 +
 +
* [[VFO-003#Output_Power_-_Power_Calculation|VFO-003 Output_Power - Power Calculation]]
 +
 +
* RMS Voltage of square wave
 +
 +
[[file:SquareWace-3.3V.PNG]]
 +
 +
* [https://www.redcrab-software.com/en/Calculator/Electrics/Rectangular-Voltage-RMS-Value Square Wave Calculator]
 +
* 2.33V^2/100 = 0.0542W
 +
* Power is split between Source and load resistors
 +
* 0.02714W
 +
 +
* dBm Calculation
 +
 +
* [https://www.rapidtables.com/convert/power/dbm-converter.html mW to dBm calculator]
 +
 +
[[file:SquareWave-3.3V_dBm.PNG]]
 +
 +
* Expect 14.3 dBm drive
 +
* Measured 12.6 dBm with [[NanoVNA]] - Pretty close
 +
* Need a 6 dB attenuator on the LO input to reduce [[VFO-003]] for Level 7 mixers (like the ADE-1 mixer)
 +
** 6 dB 150-36-150
 +
 +
===== Mixer with SSB4 IF Crystal Filter =====
 +
 +
* Mixer is driven by [[VFO-001]] 3.3V squarewave outputs
 +
** Signal output levels about 0.5 dBm
 +
** CLK0 = RF @7 MHz [[VFO-001]] output with 20 dB attenuator
 +
** CLK1 = LO @15.998,6 MHz no attenuator
 +
*** Adjusted to center of the [[W7ZOI_Filters_on_Kits_and_Parts_Boards#SSB_4_Crystal_Filter_on_Kits_and_Parts_Board|SSB4 Crystal filter]]
 +
* IF output from mixer to [[W7ZOI_Filters_on_Kits_and_Parts_Boards#SSB_4_Crystal_Filter_on_Kits_and_Parts_Board|SSB4 Crystal filter]] input
 +
* Monitor [[W7ZOI_Filters_on_Kits_and_Parts_Boards#SSB_4_Crystal_Filter_on_Kits_and_Parts_Board|SSB4 Crystal filter]] output on [[tinySA]]
 +
** No attenuator on IF output into tinySA
 +
 +
[[file:tinySA_ADE-1-MixerwCystalFilter_9MHz_center.png]]
 +
 +
* Scan from 1 to 30 MHz
 +
* Note other signals are now well into the noise floor of the [[tinySA]]
 +
** LO present but down
 +
 +
[[file:tinySA_ADE-1-MixerwCystalFilter_1_to_30MHz.png]]
 +
 +
* 16 MHz LO level
 +
* 16 dB lower with crystal filter
 +
 +
[[file:tinySA_ADE-1-MixerwCystalFilter_16MHz_LO-Suppression.png]]
 +
 +
===== Mixer with CW5 IF Crystal Filter =====
 +
 +
* Mixer is driven by [[VFO-001]] 3.3V squarewave outputs
 +
** Signal output levels about 0.5 dBm
 +
** CLK0 = RF @7 MHz [[VFO-001]] output with 20 dB attenuator
 +
** CLK1 = LO @15.997,9 MHz no attenuator
 +
*** Adjusted to center of the [[W7ZOI_Filters_on_Kits_and_Parts_Boards#CW_5_Crystal_Filter_on_Kits_and_Parts_Board|CW5 Crystal filter]]
 +
* IF output from mixer to [[W7ZOI_Filters_on_Kits_and_Parts_Boards#C_W5_Crystal_Filter_on_Kits_and_Parts_Board|CW5 Crystal filter]] input
 +
* Monitor [[W7ZOI_Filters_on_Kits_and_Parts_Boards#CW_5_Crystal_Filter_on_Kits_and_Parts_Board|CW5 Crystal filter]] output on [[tinySA]]
 +
** No attenuator on IF output into tinySA
 +
 +
[[file:tinySA_ADE-1-Mixerw_CW5CystalFilter_9MHz_center.png]]
 +
 +
* Scan from 1 to 30 MHz
 +
* Note other signals are now well into the noise floor of the [[tinySA]]
 +
** LO present but down
 +
 +
[[file:tinySA_ADE-1-Mixerw_CW5CystalFilter_9MHz_1to30MHz.png]]
 +
 +
* 16 MHz LO level
 +
* 16 dB lower with crystal filter
 +
 +
[[file:tinySA_ADE-1-MixerwCW5CystalFilter_16MHz_LO-Suppression.png]]
 +
 +
===== Mixer with CW3 IF Crystal Filter =====
 +
 +
* Mixer is driven by [[VFO-001]] 3.3V squarewave outputs
 +
** Signal output levels about 0.5 dBm
 +
** CLK0 = RF @7 MHz [[VFO-001]] output with 20 dB attenuator
 +
** CLK1 = LO @15.997,7 MHz no attenuator
 +
*** Adjusted to center of the [[W7ZOI_Filters_on_Kits_and_Parts_Boards#CW3_Crystal_Filter_on_Kits_and_Parts_Board|CW3 Crystal filter]]
 +
* IF output from mixer to [[W7ZOI_Filters_on_Kits_and_Parts_Boards#CW3_Crystal_Filter_on_Kits_and_Parts_Board|CW3 Crystal filter]] input
 +
* Monitor [[W7ZOI_Filters_on_Kits_and_Parts_Boards#CW3_Crystal_Filter_on_Kits_and_Parts_Board|CW3 Crystal filter]] output on [[tinySA]]
 +
** No attenuator on IF output into tinySA
 +
 +
[[file:tinySA_ADE-1-Mixerw_CW3CystalFilter_9MHz_center.png]]
 +
 +
* Scan from 1 to 30 MHz
 +
* Note other signals are now well into the noise floor of the [[tinySA]]
 +
** LO present but down
 +
 +
[[file:tinySA_ADE-1-Mixerw_CW3CystalFilter_9MHz_1to30MHz.png]]
 +
 +
* 16 MHz LO level
 +
* 16 dB lower with crystal filter
 +
 +
[[file:tinySA_ADE-1-MixerwCW3CystalFilter_16MHz_LO-Suppression.png]]
 +
 +
== Videos ==
 +
 +
<video type="youtube">GvadQpkZ8l0</video>
 +
 +
<video type="youtube">Mm7WfVzr1ao</video>
 +
 +
<video type="youtube">7qhY_NMNzxw</video>

Latest revision as of 18:18, 5 November 2021

K&P ADE Mixer-P1899-720px.jpg

Kits and Parts Mixers - Features in Common

  • Available as Diode Ring Mixer or ADE-1 || ADE-6 Double Balanced Diode Ring Mixer kits from Kits and Parts
  • LO, IF, RF Ports are all 50Ω
  • +7dBm Local Oscillator injection level
    • As measured into 50Ω load
      • Mixers are not linear and loads should not be measured at the mixer
  • ~5dB RF > IF conversion loss in HF region
  • IF Port
    • Full Diplexer at the IF Port
    • Low Pass Filter can be populated if used as Product Detector / Balanced Modulator
  • Board has pads (1206 SMT or 1/8W resistor pads) for optional Attenuators on RF & LO Ports
  • 3 pin, 0.1" pads at board edges allow SMA edge connectors to be used
  • Mounting holes in all 4 corners

Kits and Parts ADE-1 Mixer

ADE-1.SCH.png

ADE-1.PCB.png

ADE-1 Schematic

ADE-1 Schematic.PNG

Performance

Chart dBm-to-Volts.PNG

ADE-1 Performance.PNG

ADE-1 ElectricalSpecs.PNG

Port VWSR

  • Measured VSWR of 2.23 at 9 MHz with NanoVNA matches spec nicely

ADE-1 LO VSWR.PNG

ADE-1 IF VSWR.PNG

ADE-1 RF VSWR.PNG

ADE-1 Measurements

NanoVNA Measurements

  • No RF in
  • LO driven by NanoVNA Tx
    • About -10dBm output
  • IF output to NanoVNA Rx
  • IF at 9 MHz
    • VSWR: 2.233
    • S21 Gain: -67 dB

ADE-1.NanoVNA LO-to-IF.png

  • NanoVNA
  • No LO in
  • RF driven by NanoVNA Tx
  • IF output to NanoVNA Rx
  • IF at 9 MHz
    • VSWR: 2.216
    • S21 Gain: -42 dB

ADE-1.NanoVNA RF-to-IF.png

  • Scanning from 1 to 100 MHz

ADE-1.NanoVNA RF-to-IF 1-100MHz.png

tinySA Measurements

LO to IF port isolation
  • Driven by VFO-001 3.3V squarewave output
    • Signal level about 0.5 dBm
    • CLK0 = 9 MHz into LO port
  • Monitor IF output from mixer on tinySA
    • Output through 20 dB attenuator (tinySA set to -20dB gain)

ADE-1.tinySA RF-to-IF 9Mhz-center.png

Mixer Operation
  • Mixer is driven by VFO-001 3.3V squarewave outputs
    • Signal output levels about 0.5 dBm
    • CLK0 = RF @7 MHz VFO-001 output with 30 dB attenuator
    • CLK1 = LO @16 MHz no attenuator
  • Monitor IF output from mixer on tinySA
    • IF out to tinySA with 20 dB attenuator (tinySA set to -20dB gain)

ADE-1.tinySA LO-16MHz RF-7MHz-to-IF 9Mhz-center.png

  • Same but 9 MHz picked out
  • Approx. 8 dB insertion loss

ADE-1.tinySA LO-16MHz RF-7MHz-to-IF 9Mhz-at9MHz.png

  • Look at 7 MHz RF freq on IF output

ADE-1.tinySA LO-16MHz RF-7MHz-to-IF 9Mhz-at7MHz.png

  • Look at 16 MHz LO freq on IF output

ADE-1.tinySA LO-16MHz RF-7MHz-to-IF 9Mhz-at16MHz.png

Kits and Parts Diode Mixer

Diode Mixer Card Schematic

DBDM.SCH.png

DBDM.PCB.png

Bridged Tee Diplexer

Diplexor is a bandpass/band-stop filter popularized by Joe Reisert W1JR that is used after a double Balanced Mixer to provide a 50 ohm termination to all frequencies at the mixer's IF port, and to the following amplifier stage. Maintaining a consistent load at the mixer avoids overload and Inter-Modulation Distortion (IMD) effects that these mixers are prone to when not properly terminated.

LTSpice simulation

  • 9 MHz
  • FT37-67, 20T-12" = 8 uH
  • T37-17, 13T-10" = 250 nH
  • C2 adjusts peak from left to right

DIPLEXER SPICE SIM.PNG

Diplexer.PNG

Diplexer pass.PNG

Toroid Winding Direction

  • Toroids needs to be wound to match the pad locations/offsets on the PCB

Toroid-cw.jpg

Adjust IF Diplexer C1 (ADE-1)

  • Drive RF port from NanoVNA
    • Nominal 0 dBm drive level
  • IF port is output
  • No drive on LO
  • 9 MHz is IF design frequency
  • Nano VNA set to scan from 1 Mhz to 30 MHz
    • Shows peak expected signal around 9 MHz

ADE-1.NanoVNA RF-to-IF.png

  • Scan from 8 to 10 MHz
  • Adjust C1 to peak near 9 MHz
    • Eliminate double peaks

ADE-1.NanoVNA RF-to-IF 8-10MHz.png

ADE-1 Mixer as Product Detector

P1927-720PX.jpg

  • RF is 9 MHz from IF stage
  • LO is 9 MHz BFO from VFO-003
    • Minor adjustments to get to side of the base band offset
  • IF output is audio
    • Mixer goes down to DC
  • IF needs Audio Filter
    • IF port wants to see 50 Ohm termination across output
    • 0.33 uF cap/50 ohms terminates higher frequencies at 50 ohms
    • 1.5 mH inductor in series as filter on audio output
  • LTSpice Simulation

LP Audio-2.PNG

  • Circuit Mods

ADE-1 AF Filter-2.PNG

  • IF section

ADE-1 AF Filter Physicals-4.PNG

Typical Application

MIXER TEST.png

Si5351A Drive Level

  • Si5351A used to drive LO and/or RF ports
    • 3 outputs
    • LO at full level (+7dBm)
    • RF at various levels with attenuators to drop to expected RF signal levels
  • Don't want more than 7 dBm into LO or RF ports
  • Two Si5351 Designs to drive ADE-1 LO or RF ports
    • VFO-001
      • Uses the Si5351 without external drivers
      • Set drive levels to 2mA, 4mA, 6mA or 8mA
    • VFO-003 - Adds 50Ω drivers
      • Level is fixed
      • Three 74AC14 parts with 150 ohms outputs paralleled
      • 13 dBm output
      • Install 6 dBm attenuator on board (13-6=7)

VFO-001 drive

  • The RMS value is for square-wave voltages whose pulse duration (ti) and pause (tp) have the same length:

RMS-SquareWave.PNG

RMS-SquareWave-2.PNG

  • Drive level of 3.3V

RMS-SquareWave-3.PNG

  • 100 mW is 20 dBm
  • ADE-1 needs 7 dBm level
  • Would need a 13 dB attenuator
    • Not actually true
      • Although the Si5351 datasheet says it drives 50 Ohms loads this is not exactly the case
      • Drive levels are controlled by the output current setting
  • Si5351A outputs measured on VFO-001
    • Drive Level 2 mA = 0.2 dBm
    • Drive Level 4 mA = 6.2 dBm << Use this level
    • Drive Level 6 mA = 9.7 dBm
    • Drive Level 8 mA = 11.7 dBm

VFO-003 drive

  • RMS Voltage of square wave

SquareWace-3.3V.PNG

  • dBm Calculation

SquareWave-3.3V dBm.PNG

  • Expect 14.3 dBm drive
  • Measured 12.6 dBm with NanoVNA - Pretty close
  • Need a 6 dB attenuator on the LO input to reduce VFO-003 for Level 7 mixers (like the ADE-1 mixer)
    • 6 dB 150-36-150
Mixer with SSB4 IF Crystal Filter

TinySA ADE-1-MixerwCystalFilter 9MHz center.png

  • Scan from 1 to 30 MHz
  • Note other signals are now well into the noise floor of the tinySA
    • LO present but down

TinySA ADE-1-MixerwCystalFilter 1 to 30MHz.png

  • 16 MHz LO level
  • 16 dB lower with crystal filter

TinySA ADE-1-MixerwCystalFilter 16MHz LO-Suppression.png

Mixer with CW5 IF Crystal Filter

TinySA ADE-1-Mixerw CW5CystalFilter 9MHz center.png

  • Scan from 1 to 30 MHz
  • Note other signals are now well into the noise floor of the tinySA
    • LO present but down

TinySA ADE-1-Mixerw CW5CystalFilter 9MHz 1to30MHz.png

  • 16 MHz LO level
  • 16 dB lower with crystal filter

TinySA ADE-1-MixerwCW5CystalFilter 16MHz LO-Suppression.png

Mixer with CW3 IF Crystal Filter

TinySA ADE-1-Mixerw CW3CystalFilter 9MHz center.png

  • Scan from 1 to 30 MHz
  • Note other signals are now well into the noise floor of the tinySA
    • LO present but down

TinySA ADE-1-Mixerw CW3CystalFilter 9MHz 1to30MHz.png

  • 16 MHz LO level
  • 16 dB lower with crystal filter

TinySA ADE-1-MixerwCW3CystalFilter 16MHz LO-Suppression.png

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