NorCal NC40A

Simplified Assembly Instructions


 

NorCal NC40A Simplified Assembly Document
Chuck Adams – K7QO
Thanks to Wayne Burdick, N6KR, for the use of the NorCal40A as a teaching exercise on qrp-tech in anticipation of the 25th anniversary of the transceiver. Thousands are assembled and ready to operate. The anniversary party is to get them all back on the air and making noise in the ionosphere and music in the ears of operators worldwide.
The series of assembly steps shown here are a minimal assembly manual for all who wish to build the NorCal40A from the QRP-Tech PCB. Experienced builders should not have problems. Others are asked to get local help, if possible, in order to avoid pitfalls and possible failure of the project. Don’t be afraid to seek help.
====== Phase 1 – Power Supply =========
Assembly steps.
o Install 4-40 x 5/8″ screw, and 4-40 nut onto PCB at each corner hole as standoffs to prevent shorts during power-up tests.
o J2 — Power Input & Power Switch Header – 4-Pin 0.1″ Wafer-Style Friction-Lock Male Header
Solder 4-Pin Male Header to PCB at location J2. Install Locking Tab towards center of PCB
o J2 — Power Input Jack – Connect 2.1mm Coaxial Power Jack to right 2 pins of J2 Female Connector
Crimp a Female Terminal to one end of the BLK wire. The BLK wire connects to J2 Pin 3 (GND)
Solder the other end of the BLK wire to the Power Input Jack Outer Barrel (GND)
Crimp a Female Terminal to one end of a RED wire. This RED wire connects to J2 Pin 4 (+12V DC)
Solder the other end of the RED wire to the Power Input Jack Center Pin (+12V DC Input)
Install both BLK and RED terminal ends into the 4-Pin Connector Shell (BLK – Pin 3, RED – Pin 4)
o S1 — SPDT Power On/Off switch – Connect S1 to left 2 pins of J2 Female Connector
Crimp a Female Terminal to one end of a RED wire. This RED wire connects to J2 Pin 1
Solder the other end of the RED wire to S1 Outer Pin
Crimp a Female Terminal to one end of another RED wire. This RED wire connects to J2 Pin 2
Solder the other end of the RED wire to S1 Center Pin
Install both RED Terminal ends into the 4-Pin Connector Shell (Outer – Pin 1 and Center – Pin 2)
o D7 — 1N5817 or 1N5818 Schottky Diode – Note Banded End of Diode on PCB
o C43 — 47nF Disc or Mono Capacitor (473)
o C42 — 10uF 25V Electrolytic Capacitor
o U5 — 78L08 TO-92 3-Pin Voltage Regulator IC
o C54 — 47nF Disc or Mono Capacitor (473)
o C8 — 47nF Disc or Mono Capacitor (473)
o C41 — 100uF 25V Electrolytic Capacitor
Testing.
o Power up.
o Measure current, if possible. Should be about 2mA or so.
o U1 Pin-8 voltage measured ~ 8V.
o U2 Pin-8 voltage measured ~ 8V.
o U3 Pin-6 voltage measured ~ 8V.
====== Phase 2 – AF AMP =======================
Assembly steps.
o J3/J4 — PCB Audio Output & Key Input Header – 4-Pin 0.1″ Wafer-Style Friction-Lock Male Header
Solder 4-Pin Male Header to PCB at location J3/J4. Install Locking Tab towards center of PCB
o J4 — Audio Output Jack – Connect 3.5mm Female Stereo Jack to right 2 pins of J3/J4 Female Connector
Crimp a Female Terminal to one end of a BLU wire. The BLU wire connects to J3/J4 Pin 3 (GND)
Solder the other end of the BLU wire to the Audio Output Jack Outer Barrel (GND)
Crimp a Female Terminal to one end of a WHT wire. This WHT wire connects to J3/J4 Pin 4 (Audio Out)
Solder the other end of the WHT wire to the Audio Output Jack Tip Connection (Audio Out)
Install both BLU and WHT Terminal ends into the 4-Pin Header Shell (BLU – Pin 3, WHT – Pin 4)
Install a short wire jumper between Tip and Ring terminals of Audio Output Jack – This jumper will feed mono audio output from the AF Amplifier to both left and right audio channels of headphones or speakers
o J3 — Key Input Jack – Connect 3.5mm Female Mono Jack to left 2 pins of J3/J4 Female Connector
Crimp a Female Terminal to one end of a GRN wire. The GRN wire connects to J3/J4 Pin 2 (Key GND)
Solder the other end of the GRN wire to the Key Input Jack Outer Barrel (Key GND)
Crimp a Female Terminal to one end of a WHT wire. This WHT wire connects to J3/J4 Pin 1 (Key Tip)
Solder the other end of the WHT wire to the Key Input Jack Tip Connection (Key Tip)
Install both GRN and WHT Terminal ends into the 4-Pin Header Shell (GRN – Pin 2, WHT – Pin 1)
o C26 — 10uF 25V Electrolytic Capacitor
o Rz — 10 ohm Resistor (BRN-BLK-BLK-GLD-BRN 1%) (mod to NC40A – Zobel filter)
o Cz — 100nF Disc or Mono Capacitor (104) (mod to NC40A – Zobel filter)
o R8 — 500 ohm Trimmer Resistor (501) – PCB mounted Audio Gain Control (Volume)
o R22 — 1.8K Resistor (BRN-GRY-BLK-BRN-BRN 1%)
o C27 — 100uF 25V Electrolytic Capacitor
o C55 — 10nF Disc or Mono Capacitor (103)
o U3 — 8-Pin DIP IC Socket
o C23 — 2.2uF 25V Electrolytic Capacitor
o C22 — 10nF Disc or Mono Capacitor (103)
o R7 — 47K Resistor (YEL-VIO-ORG)
o U3 — LM386N 8-Pin DIP IC – Mount IC in Socket
Testing.
o R8 — Turn Audio Gain Pot fully Counter Clockwise to minimize volume.
o Plug amplified PC speakers into Audio Output Jack, and set at reduced volume.
o Turn power supply on.
o Turn volume up to see if you hear a hiss. Hiss will be extremely faint. Wear headphones if required.
o Test Probe made from 15cm 22AWG Solid insulated wire with 1mm exposed, probe either end of R7. Should hear an increase in noise level in speakers.
====== Phase 3 – AGC and Mute Circuits =======================
Assembly steps.
o C29 — 10uF 25V Electrolytic Capacitor
o C30 — 2.2uF 25V Electrolytic Capacitor
o D6 — 1N5817 or 1N5818 Schottky Diode
o D5 — 1N5817 or 1N5818 Schottky Diode
o R5a-d — 2.2M 8-Pin SIP Resistor Network or 4ea 2.2M 1% Thin-Film Resistors (RED-RED-BLK-YEL-BRN)
o D1 — 1N4148 Silicon Diode
o D2 — 1N4148 Silicon Diode
o D3 — 1N4148 Silicon Diode
o D4 — 1N4148 Silicon Diode
o C28 — 100nF 100V Mylar Capacitor (104)
o C20 — 100nF 100V Mylar Capacitor (104)
o C21 — 100nF 100V Mylar Capacitor (104)
o C19 — 10nF Disc or Mono Capacitor (103)
o Q2 — J113 JFET
o Q3 — J113 JFET
o R3 — 150K Resistor (BRN-GRN-YEL)
o R4 — 8.2M Resistor (GRY-RED-GRN) (this may be changed later to adjust sidetone level)
o R6 — 10K Trimmer Resistor (103) – PCB mounted AGC Threshold Control
Testing.
o Set R6 to mid position.
o Power up transceiver. Touch test probe at pads Pin-4 and Pin-5 of U2. An increase in background noise should be heard in speaker or headphones. The hiss will disappear and then come back after a few seconds or so.
o R6 can be adjusted later for threshold level of AGC.
====== Phase 4 – Product Detector and BFO =================
Assembly steps.
o C17 — 50pF Variable Capacitor (8-50pF Mica Trimmer – YEL)
o X5 — 4.915 MHz crystal
o U2 — 8-Pin DIP IC Socket
o C15 — 2.2uF 25V Electrolytic Capacitor
o C14 — 47pF Disc or Mono Capacitor (470 or 47)
o C18 — 270pF Disc or Mono Capacitor (271)
o U2 — NE602A 8-Pin DIP IC – Mount IC in Socket
Testing.
o Power up. Touch test probe to right pad of L4 or U2 Pin-2, and you should hear an increase in noise in the speaker or headphones.
o If you have an AFA or frequency counter, see if you can measure a frequency reading on Pin-7 of U2. There is an empty pad to the right of C17 for this purpose.
o If you have a crystal oscillator, take one of the other IF crystals and power up the oscillator with one of the crystals in it. With the oscillator near the NC40A, you should hear a tone in the speaker or headphones.
o Adjustment of C17 should vary the tone heard with external signal source.
o Measure about 1.4V or so at U6 Pin-5 and U6 Pin-2 with a DMM.
====== Phase 5 – IF Crystal Filter ======================
Assembly steps.
o L4 — 18uH Molded Inductor (Green RF Choke) (BRN-GRY-BLK)
o C13 — 270pF Disc or Mono Capacitor (271)
o C12 — 270pF Disc or Mono Capacitor (271)
o C11 — 270pF Disc or Mono Capacitor (271)
o C10 — 270pF Disc or Mono Capacitor (271)
o C9 — 270pF Disc or Mono Capacitor (271)
o X1 — 4.915 MHz crystal
o X2 — 4.915 MHz crystal
o X3 — 4.915 MHz crystal
o X4 — 4.915 MHz crystal
Testing.
o Power up transceiver as before.
o Touch test probe to either pad of C9 or pad 3 of T3 and you should hear an increase in noise in the speaker or headphones. Note that the frequency range of the noise is reduced from previous tests because of the band pass frequency range of the IF filter. The noise level will be reduced in amplitude also.
====== Phase 6 – Receive Mixer =============================
Assembly steps.
o T3 — FT37-61 Black Toroid Transformer – 23T 16″ #28 RED (Primary), 6T 6″ #26 GRN (Secondary).
Note: Wind all toroids in a Counter-Clockwise direction to maintain proper RF phase and PCB fit.
Refer to the Wilderness Radio NorCal 40A assembly manual (Pages 10-12) for proper winding directions
o C6 — 47pF Disc or Mono Capacitor (470 or 47)
o C5 — 10nF Disc or Mono Capacitor (103)
o C4 — 5pF (4.7pF) Disc or Mono Capacitor (4.7)
o U1 — 8-Pin DIP IC Socket
o U1 — NE602A 8-Pin DIP IC – Mount IC in socket
Testing. – No test at this time without VFO operating.
====== Phase 7 – Receiver Bandpass Filter (BPF) and Muting Circuit =====================
Assembly steps.
Rcvr Bandpass Filter.
o T2 — FT37-61 Black Toroid Transformer – 20T 14″ #26 GRN (Primary), 1T 2″ #26 GRN (Secondary). Wind Counter-Clockwise.
o C2 — 50pF Variable Capacitor (8-50pF Mica Trimmer – YEL)
o R2 — RF Gain Control Header – 3-Pin 0.1″ Wafer-Style Friction-Lock Male Header
o S2 — PCB RIT Switch Header – 3-Pin Male Wafer-Style Friction-Lock Male Header
o R16 — PCB RIT Control Header – 2-Pin 0.1″ Wafer-Style Friction-Lock Male Header
Note: Fit and Install Headers at R2, S2, and R16 as a single unit for proper fit
Place the Shells over the Header Pins of all three headers, and align them side-by-side on the PCB
Check for proper fit. The Shells are slightly wider than the Headers and it may be necessary to remove some material from the mating edges of the Shells by sanding them on a flat surface
When satisfied with the fit, hold all three in position on the PCB and solder a single pin on each Header. Check again for proper fit, adjust if necessary by re-flowing the solder joint, and solder the remaining pins
o R2 — 1K RF Gain Potentiometer. Connect 1K Pot to 3-Pin Female Wafer-Style Friction-Lock Header Shell
Looking at the Knob end of RF Gain Pot R2 the pins are (Left – CCW) (Center – Wiper) (Right – CW)
Crimp a Female Terminal to one end of a YEL wire. Check for continuity.
Solder the free end of the YEL wire to the (Right – CW) Pin of RF Gain Pot R2
Crimp a Female Terminal to one end of a WHT wire. Check for continuity.
Solder the free end of the WHT wire to the (Center – Wiper) Pin of RF Gain Pot R2
Crimp a Female Terminal to one end of a BLK wire. Check for continuity.
Solder the free end of the BLK wire to the (Left – CCW) Pin of RF Gain Pot R2
Install the YEL, WHT, and BLK Terminal ends into the 3-Pin Header Shell (BLK – Pin 1, WHT – Pin 2, YEL – Pin 3)
Note: Optional – Install a Berg jumper across Pins 2-3 at R2 to simulate pot set to maximum gain for testing.
o L1 — 15uH Molded Inductor (Green RF Choke) (BRN-GRN-BLK)
o C1 — 50pF Variable Capacitor (8-50pF Mica Trimmer – YEL)
Muting circuit.
o Q1 — 2N3904 NPN transistor
o C3 — 47nF Disc or Mono Capacitor (473)
o R1 — 1.8K 1/4W Resistor (BRN-GRY-RED)
Testing. – No testing done at this time.
====== Phase 8 – VFO Section and RIT =======================
Assembly steps.
o C7 — 10nF Disc or Mono Capacitor (103)
o C32 — 150pF Disc or Mono Capacitor (151)
o R23 — 1.8K Resistor (BRN-GRY-RED)
o RFC2 — 1mH Molded Inductor (Note: Tan RF Choke – Looks like a 1/4W resistor) (BRN-BLK-RED-SLVR)
Note: This choke has proven to be subject to failure. We suspect the failure is due to either high electrical or RF currents in the circuit that exceed it’s 38mA rating, or more likely due to excess soldering heat applied during installation. We suggest using one of the following substitutes if you experience VFO problems during testing:
Alternate 1 (Tested) – Fair-Rite 73 Shield Bead #2673000801, 12T 14″ #28-32 Wire (10T = 600uH, 12T 1mH)
Alternate 2 (Not-Tested) – FT37-43 Black Toroid, 53-54T 30″ #32 Wire (53.5T = 1000uH = 1mH)
o Q8 — J113 JFET
o C52 — 1200pF Polystyrene Capacitor (1200)
o C53 — 1200pF Polystyrene Capacitor (1200)
o D9 — 1N4148 Silicon Diode
o R21 — 47K Resistor (YEL-VIO-ORG)
o C51 — 390pF Polystyrene Capacitor (390)
o L9 — 21uH Toroid Inductor, T68-7 White Toroid, 60T 56″ #28 RED. Wind Counter-Clockwise.
After soldering L9 in place on PCB, secure with 6-32 nylon screw, washers, and nut from underneath.
o C50 — 2-25pF Air Variable Capacitor – Adjust to bring the lower end of the VFO tuning range to desired value
Note: the provided air variable cap may require adding an additional NP0 cap in parallel across it’s terminals on the bottom side of the PCB
o C49 — 47pF NPO or C0G cap (470)
o D8 — MVAM109 2-Pin TO-92 Varactor Diode – this will determine the bandwidth of the tuning range
o R19 — 47K Resistor (YEL-VIO-ORG)
o R20 — 4.7K Resistor (YEL-VIO-BLK-BRN 1%)
o R15 — 510 ohm Resistor (GRN-BRN-BRN)
o U6 — 8-Pin DIP IC Socket
o U6 — LM393 8-Pin DIP IC – Mount IC in Socket
o R17 — PCB Tuning Control Header – 2-Pin 0.1″ Wafer-Style Friction-Lock Male Header
Solder 2-Pin Male Header to PCB at location R17. Install Locking Tab towards center of PCB
o R17 — 10K Tuning Potentiometer – Connect 10K Pot to 2-Pin Female Friction-Lock Connector Shell
Looking at the Knob end of Tuning Pot R17 the pins are (Left – CCW) (Center – Wiper) (Right – CW)
Crimp a Female Terminal to one end of a GRN wire. Check for continuity.
Solder the free end of the GRN wire to the (Right – CW) Pin & also to the (Center – Wiper) of the Tuning Pot R17
Crimp a Female Terminal to one end of a BLU wire. Check for continuity.
Solder the free end of the BLU wire to the (Left – CCW) Pin of the Tuning Pot R17
Install the GRN, and BLU Terminal ends into the 2-Pin Header Shell (BLU – Pin 1, GRN – Pin 2)
o R16 — PCB RIT Control Header – 2-Pin 0.1″ Wafer-Style Friction-Lock Male Header (Installed in step 7)
o R16 — 1K RIT Control Potentiometer – Connect 1K Pot to 2-Pin Female Wafer-Style Friction-Lock Connector Shell
Looking at the Knob end of RIT Control Pot R16 the pins are (Left – CCW) (Center – Wiper) (Right – CW)
Crimp a Female Terminal to one end of a YEL wire. Check for continuity.
Solder the free end of the YEL wire to the (Right – CW) Pin & also to the (Center – Wiper) of the RIT Control Pot R16
Crimp a Female Terminal to one end of a BRN wire. Check for continuity.
Solder the free end of the BRN wire to the (Left – CCW) Pin of the RIT Control Pot R16
Install the YEL, and BRN Terminal ends into the 2-Pin Header Shell (BRN – Pin 1, YEL – Pin 2)
o S2 — PCB RIT Switch Header – 3-Pin Male Wafer-Style Friction-Lock Male Header (Installed in step 7)
o S2 — SPDT RIT Switch – Connect to 3-Pin Female Wafer-Style Friction-Lock Connector Shell
Looking at the side of the RIT Switch S2 the pins are (Top – RIT Off) (Center – Common) (Bottom – RIT On)
Note: The switch body has physical markings as follows (Top – On) (no center marking) (Bottom – On)
Crimp a Female Terminal to one end of a YEL wire. Check for continuity.
Solder the free end of the YEL wire to the (Bottom – RIT On) Pin of RIT Switch S2
Crimp a Female Terminal to one end of a WHT wire. Check for continuity.
Solder the free end of the WHT wire to the (Center – Common) Pin of RIT Switch S2
Crimp a Female Terminal to one end of a BRN wire. Check for continuity.
Solder the free end of the BRN wire to the (Top – Rit Off) Pin of RIT Switch S2
Install the YEL, WHT, and BRN Terminal ends into the 3-Pin Header Shell (YEL – Pin 1, WHT – Pin 2, BRN – Pin 3)
Testing.
o If you have a frequency counter, power on and measure frequency at U1 Pin-6, the VFO input into the receiver mixer. With RIT off, adjust VFO tune pot to lowest frequency of the VFO. Make adjustments to get this reading to the lowest range of operation on 40M that you want to receive.
Usually this will be approximately 7.025MHz
Note: The measured VFO frequency must be added to the IF frequency to get the actual tuned frequency.
We are looking for a measured VFO frequency in the range of 2.085 MHz – 2.125 MHz
The IF Frequency is approximately 4.915 MHz based upon our set of matched crystals
2.085 MHz + 4.915 MHz = 7.000 MHz
2.125 MHz + 4.915 MHz = 7.040 MHz
====== Phase 9 – Key Switch Circuit =====================
Assembly steps.
o J3 — Keyer Input Header, Connector, and Jack – Previously installed in Step 2
o Q4 — 2N3906 PNP Transistor
o R24 — 150K Resistor (BRN-GRN-YEL)
o R9 — 47K Resistor (YEL-VIO-ORG)
o D11 — 1N4148 Silicon Diode
o C57 — 47nF Disc or Mono Capacitor (473)
o C36 — 47nF Disc or Mono Capacitor (473)
o R25 — 100 ohm Resistor (BRN-BLK-BRN)
o C48 — 10nF Disc or Mono Capacitor (103)
Testing.
o Power up transceiver.
o See if receiver can hear any 40m signals with short wire CAREFULLY touching pad common C44, L7 or C45. You should hear at least atmospheric noise levels. Adjust C1 for maximum noise.
o Short keyline at J3 to ground or use a straight key attached to J3.
o Receiver should mute when keyline is shorted or straight key is pressed.
o Approximately 8V should be read at U4 Pin-8 when keyline is shorted to ground. After short or key closure is removed, receiver should become active again. Delay may occur due to muting time constant.
====== Phase 10 – Transmit Mixer, Bandpass Filter, and Buffer =====================
Assembly steps.
o C31 — 5pF (4.7pF) Disc or Mono Capacitor (4.7 or 5)
o C38 — 100pF Disc or Mono Capacitor (100 or 101)
o C34 — 50pF Variable Capacitor (8-50pF Mica Trimmer- YEL)
o C39 — 50pF Variable Capacitor (8-50pF Mica Trimmer- YEL)
o C35 — 270pF Disc or Mono Capacitor (271)
o C37 — 5pF (4.7pF) Disc or Mono Capacitor (4.7 or 5)
o C33 — 47nF Disc or Mono Capacitor (473)
o R10 — 510 ohm Resistor (GRN-BRN-BRN)
o L6 — 2.5uH Toroid Inductor – T37-2 Red Toroid 28T 16″ #28 RED. Wind Counter-Clockwise.
o L5 — 18uH Molded Inductor (Green RF Choke) (BRN-GRY-BLK)
o X6 — 4.915 MHz Crystal
o Q5 — J113 JFET
o R11 — 510 ohm Resistor (GRN-BRN-BRN)
o U4 — 8-Pin DIP IC Socket
o U4 — NE602A 8-Pin DIP IC – Mount IC in socket
Testing.
o power up transceiver
o key the transmitter
o should hear a weak tone in the receiver
Note: Tone is extremely weak (almost inaudible) – use Headphones during testing
o adjust C34 to see if tone changes and set to desired tone for monitoring while operating CW
========== Phase 11 – Transmit Driver circuit ===============
Assembly steps.
o Z1 — FB-43 ferrite bead – Mount ferrite bead on base lead of Q6 (Center – Base)
o Q6 — PN2222A TO-92 plastic transistor with FB-43 ferrite bead mounted on Base lead
Note: Viewed from Flat Side. Pin 1 (Left) – Emitter, Pin 2 (Center) – Base, Pin 3 (Right) – Collector
o R12 — 20 ohm Resistor (RED-BLK-BLK)
o R13 — 500 ohm Trimmer Resistor – PCB mounted Drive Gain Adjust Potentiometer (set full CCW)
o C56 — 10uF 25V Electrolytic Capacitor
o D10 — 1N5817 or 1N5818 Schottky Diode
o C48 — 10nF Disc or Mono Capacitor (103) (Installed in Phase 9)
o T1 — FT37-43 Black Toroid with Orange Dot – 14T 10″ #26 GRN (Primary), 4T 4″ #28 RED (Secondary)
o R14 — 100 ohms Resistor (BRN-BLK-BRN)
Testing.
o power up transceiver
o key transmitter
o tone heard in receiver should increase as R13 is turned clock-wise.
Note: Tone is extremely weak (almost inaudible) – use Headphones during testing
=====================================================================================
WARNING. From this point forward, the transceiver should NEVER be keyed without a 50 ohm dummy load on
the antenna output connector or a tuned antenna for 40 meters. The PA will be damaged due to high SWR and
the resulting voltages on the collector of the PA if this is not done.
=====================================================================================
=========== Phase 12 – Transmitter PA and LPF ========================
Assembly steps.
o J1 — PCB Antenna Jack Header – 3-Pin 0.1″ Wafer-Style Friction-Lock Male Header.
Modify the header by removing the center Pin before soldering it onto the PCB.
o J1 — Antenna BNC Jack – Connect BNC Jack to 3-Pin 0.1″ Wafer-Style Female Connector Shell
Crimp a Female Terminal to one end of the RED wire. The RED wire connects to J1 Pin 1 (Signal)
Solder the other end of the RED wire to the Center Pin of the BNC Connector
Crimp a Female Terminal to one end of the BLK wire. The BLK wire connects to J1 Pin 3 (Shield/GND)
Solder the other end of the BLK wire to the Ground Lug of the BNC connector
Install both RED and BLK terminal ends into the 3-Pin Connector Shell (RED – Pin 1, BLK – Pin 3)
o R18 — 1K Resistor (BRN-BLK-BLK-BRN-BRN 1%)
o RFC1 — 18uH Molded Inductor (Green RF Choke) (BRN-GRY-BLK)
o C44 — 47nF Disc or Mono Capacitor (473)
o C45 — 330pF Disk or Mono Capacitor (331)
o C46 — 820pF Disk or Mono Capacitor (821)
o C47 — 330pF Disk or Mono Capacitor (331)
o D12 — 1N4755A 43V 1W Zener Diode
o L7 — 1.3uH Toroid Inductor – T37-2 Red Toroid, 18T 12″ #26 GRN. Wind Counter-Clockwise.
o L8 — 1.3uH Toroid Inductor – T37-2 Red Toroid, 18T 12″ #26 GRN. Wind Counter-Clockwise.
o Q7 — 2SD882 NPN Final PA Transistor – Mount via inline pads on PCB
Note: Viewed from Text side. Pin 1 – Emitter, Pin 2 – Collector (Common to Mounting Tab/Heat Sink), Pin 3 – Base
Final Testing and Alignment.
Please refer to pages 15-18 of the Wilderness Radio NC40A Assembly and Operating Manual for complete alignment and testing procedures.
===========================================================
See Qrp-Tech at groups.io for information and help, if needed.
73, and Good Luck!
Chuck Adams – K7QO