background image

Page 

1

 of 

8

 

 

 

 

efhw_tuner_assy_090110.pdf

 

 
 

  QRPGuys EFHW 40m-15m Mini Tuner Assembly Manual

 

 

 

     

 

 

 

 

 

 

 

First, familiarize  yourself  with  the  parts  and check for  all  the  components.  If  a  part  is missing,  please 
contact us and we will send one. You must use 

[email protected]

 to request a part.  

 

Parts List

 

 
1 – QRPGuys EFHW Tuner PCB 
1 – Slide switch – DPDT 
1 – C1, polyvaricon, w/shaft and mtg. hardware, 1 long, 2 short metric screws, and nylon spacer 3/8”L 
1 - T50-6 toroid core (yellow) 
1 – FT37-43 toroid core (black) 
1 – 48” of 26AWG magnet wire for the toroids 
1 – Medium size control knob 
1 - BNC PCB connector 
2 – 4mm x 30mm long SS Phillips screw 
4 – 4mm nut 
2 – 4mm lock washer 
2 – 4mm SS wing nut 
2 – 4-40 x 1/2” long nylon screw 
2 – 4-40 nylon nut 
2 – 3/8” diameter #4 nylon washer 
2 - 1/8”diameter x 1/2” long vinyl Caplug 
1 – C2, .1uF mono capacitor, marked 104 
1 – D1, Red LED w/clear lens 
1 – R4, 470 ohm resistor (yellow-violet-brown-gold) 
3 – R1-3, 51 ohm 2W power resistor (green-brown-black-gold, or value is printed on the component) 
1 – D2, 1N4148 signal diode, sm. glass, w/black band on one end 
1 – 8mm round self-adhesive rubber foot 
 
 
 

Summary of Contents for EFHW

Page 1: ...6 toroid core yellow 1 FT37 43 toroid core black 1 48 of 26AWG magnet wire for the toroids 1 Medium size control knob 1 BNC PCB connector 2 4mm x 30mm long SS Phillips screw 4 4mm nut 2 4mm lock wash...

Page 2: ...w as to which is front and back of the PCB Install D1 the clear lens LED on the FRONT side of the board The polarity must be correct The short lead is negative and goes towards the top of the board Th...

Page 3: ...e the two toroids on the BACK side of the board For L1 use the T50 6 yellow core and 24 of the supplied magnet wire You are winding a total of 23 turns with a tap at 3 turns from the beginning of wind...

Page 4: ...trim to 1 4 long and tin the leads prior to soldering them to the backside of the board The magnet wire supplied Is Thermaleze brand and will tin easily with a soldering iron Always tin the leads bef...

Page 5: ...on the PCB and centered on the screw hole You will notice the tap hole is indicated and is slightly larger in diameter to accept the double twisted wire Install the toroid flush with the backside of t...

Page 6: ...oard and secure it with the two short metric Phillips screws from the top Solder and clip the three leads flush Install the slide switch on the FRONT side of the board soldering all four corners and e...

Page 7: ...brilliance your SWR is approximately 2 1 and the LED will completely extinguish at 1 1 Tip from Dan If your led does not go out at 1 1 there may be a little too much gain on L2 the indicator transfor...

Page 8: ...u use a counterpoise try to lay it out in a straight line when possible Additionally after the antenna is tuned up keeping the bridge in the circuit Tune position will reduce the power by a factor of...

Reviews: