JJJelectronics- 2 band HF transceiver 40m/80m

* Output power: 2.0w RF.

* Frequency 3.48-3.82MHz /6.98-7.13MHz

* Output impedance 50 ohm.

* Voltage 10v-14v

* Double side board

* Protection diode for wrong polarity

* Side tone stage so that you can hear the mores tone when you transmit.

*Audio power amplifier

* LED power indicator

* Terminal for frequency counter

* Terminal for S-meter

Tool required.

Soldering iron (25w-40w), small cutter, trimming tool for coils and 50 ohm load resistor for

testing the transmitter.

Now let’s build the transceiver

I would recommend fitting the parts in the order they appear in the part list.

Resistor first, then semiconductors, coils and Capacitors.

Make sure you put the electrolytic capacitors and diodes in the right way round .keep all

components leads as short as possible.

When you have finished assembly of the board, check all the parts are in the right places.

The soldering looks bright and good. Re-solder any suspect joints with a little fresh solder, check

that there are no short or splashes of solder between tracks.

When you are sure all is well, connect up a power meter or SWR bridge and a 50 ohm dummy

load of at least 5w rating. Link a Morse key to” K1” and “K2” terminals. Connect the transmitter

to a suitable power supply (the right way round please).

Do not hold the key down for long periods at full power; the heat sink is rated for normal CW

use

Resistors

R1 33k 1

R2, R26 56k 2

R3 5k6 1

R4, R7, R13, R23 47R 4

R5 27R 1

R6 100R 1

R15 short Solder a wire instead

R9 2R2 1

R10, R24, R29, R33 1k 4

R11 1M 1

R12,R8 2k7 2

R14, R28, R35 150R 3

R16 220R 1

R17 15k 1

R18, R19, R20, R21,R25 100k 5

R27, R34 47k 2

R31 120R 1

Transistor, Diode and IC

D1, D2, D6, D7, D8, D11,D4 1N4148 7

D3, D5, D9 8.2v Zener 3 Zener diode

D12 5.1v Zener 1 Zener diode

D13 1N4004 1

LED1 3mm LED 1

IC1 MC3361P 1

IC2 LM386 1

IC5 555 1

Q1 Bf245 1

Q2, Q4 PN2222 2

Q3 2SC1162 1

Q5, Q6 See note 2

Please check the polarity of each diode they should be installed in the board as the outline

printed on the board shows

Coils

L7, L10 220uH Red-red-brown

L2, L8 Variable inductor 2

L3, L4 Variable inductor 2

L6 Toroid black 1

L9, L11 toroid red 2

L5, L12 toroid yellow 2

L1 1mH Brown-black-red

T2 Binocular ferrite core 1

Binocular ferrite core, T2

You have to make 2 coils

Wind 4 turns of the thin enameled yellow wire tightly onto the two holes balun core. Passing the

wire through one hole and then back out of the other counts as one turn. Do this 4 times for foure

turns. Both ends of the wire should project from the same side as shown.

Wind 1 turn of the enameled yellow wire as shown. Passing the wire through one hole and then

back out of the other counts as one turn

You have to remove the varnish from the enameled wire ends, you can use fine sandpaper or you

can use hobby knife.

Solder the T2 as shown below , the 1 turn to 1T and 4 turn to 4T

Toroids

5 toroids

2 red toroids, 2 yellow toroids and one small black toroids

For yellow toroids (L9 and L11) use thick wire (22SWG) and wind 11 turns , Passing the wire

through the hole and then back out, counts as one turn, picture for illustrated only

You have to remove the varnish from the enameled wire ends, you can use fine sandpaper or you

can use hobby knife.

Yellow toroid has 11 turns of thick wire (22SWG)

For red toroid ( L5 and L12)use thick wire (22SWG) and wind 20 turns , Passing the wire

through the hole and then back out, counts as one turn

For small black toroids use thin wire (28SWG) and wind 20 turns , Passing the wire through the

hole and then back out, counts as one turn , picture for illustrated only

Small black toroid has 20 turns (28SWG)

Capacitors

C1, 100pf 2 Marked 101

C2 220pf 1 Marked 221

C3, C5 22pf 2

C4, C11, C39 47nf 3 Marked 473

C6, C35 1nf 2

C7, C13, C14, C19, C34, C48, C51 10nf 7 Marked 103

C8, C50 See note 1 2

C9, C49 See note 1 2

C10, C42 NPO See note 1 2

C12, C29 47uf/25v 2

C15, C17, C20, C24, C25, C28, C30, C31, C32, C33, C36,

C40, C47

100nf 13 Marked 104

C16, C37 100uf/25v 2

C18, C27 10uf/16v 2

C21 See note 1 1

C22 10pf 1

C23 See note 1 1

C26 220uf/25v 1

C41 NPO See note 1 1

C43, C44 NPO See note 1 2

C46 NPO See note 1 1

C45 NPO See note 1 1

C12, C29, C16, C27, C18, C26 and C37 are electrolytic capacitors and must be installed the

correct way round. The Longest lead is normally positive, this lead should go to the hole marked

“+“on the circuit board.

Solder the yellow relay, variable resistor (volume) 2 way switch all coils , toroids and pin

terminals.

Solder a piece of wire between J1 and J2

Note 1 : you will get the capacitors values on a paper with your purchase

Power transistor and heat sink The TRX300 come with Small heat sink and heat transfer pad

Screw the transistor to the heat sink with heat transfer pad

It is really important to put the heat transfer pad between the

transistor and the heat sink otherwise you will damage the power

transistor

The pad must be placed between the transistor and the heat sink. The metal insert in the transistor

is the side of the device that must be towards the heat sink

Cut and bend one leg of the transistor (emitter) as shown

. Bend the 2.2R resistor 0.5 watt as shown

Then solder them as shown

Then insert and solder the transistor to PCB as shown

How to fix the standard heat sink with BNC, speaker socket (6.35mm

This is an option only

This a standard heat sink come with BNC for antenna, 6.35mm speaker

socket ,heat transfer pad and 3 screws/nuts

Please follow same procedure for the transistor and resistor 2.2R. The heat sink has 2 holes which can be fit directly to the 2 holes on the board with 2 screws and nuts (M2 screws and M2 nuts)

First: fixed the power transistor with M3 screw and nut, don’t forget the

heat transfer pad

It is really important to put the heat transfer pad between the

transistor and the heat sink otherwise you will damage the power

transistor

Second: after that you can fix the heat sink to the board using screw and nut and then

solder the transistor