Related Manuals for QRP Labs QDX
Summary of Contents for QRP Labs QDX
- Page 1 QDX: QRP Labs Digital Xcvr (transceiver) Assembly, design and operating manual QDX assembly Rev 1.00...
- Page 2 2.3 Inventory parts..............................12 2.4 Install all the ceramic capacitors..........................13 2.5 Install 1N4007 diodes............................14 2.6 Install PA transistors............................15 2.7 Install QRP Labs QDX TCXO module........................16 2.8 Assemble and install transformer T1........................17 2.9 Prepare and install tapped inductor L12......................22 2.10 Wind and install L14............................25 2.11 Install Low Pass Filter toroids..........................26...
- Page 3 Typical performance measurements are shown in the measurements section. The operation section will get you started with QDX and your WSJT-X or other digi modes software in minutes. PLEASE READ THE BASIC ASSEMBLY AND USE INSTRUCTIONS IN...
- Page 4 IMPORTANT! QDX produces 5 W power output from a supply voltage of 9V or a little over. At 12 V QDX could be producing 8 W power output which is likely to cause over-heating and perhaps failure of the BS170 final transistors.
- Page 5 Use of a good quality soldering iron and solder is highly recommended for best results! The following diagrams show the PCB layout and track diagrams of the QDX. Tracks shown in BLUE are on the bottom layer. Tracks shown in RED are on the top layer. There are only two layers (nothing is hidden in the middle).
- Page 6 QDX assembly Rev 1.00...
- Page 7 QDX assembly Rev 1.00...
- Page 8 QDX assembly Rev 1.00...
- Page 9 C15, 16, 17, 21, 22, 23, 24, 25, 26, 33, 35, 37, 39, 40, 41, 43, 46, 47, 49, 51, 53 2.2uF C1, 2, 3, 4, 8, 34, 38, 42, 48, 50, 52 220uF 16V electrolytic Extra DC supply capacitor (see text) QDX assembly Rev 1.00...
- Page 10 T37-6 toroid (yel), 393 nH (11t) L4 T37-6 toroid (yel), 1.20 uH (20t) L8 T37-6 toroid (yel), 525 nH (13t) L10 T50-2 toroid – tapped, see text L12 FT37-43 10t BN43-202 binocular, 3:3 FT37-43 10t trifilar QDX assembly Rev 1.00...
- Page 11 Top, Bottom Extruded aluminium top and bottom cover Front panel Laser etched, drilled for 3mm LED Rear panel Laser etched, drilled for three connectors M2.5 machine screw Screws to secure end panels Rubber foot Self-adhesive rubber foot QDX assembly Rev 1.00...
- Page 12 2.3 Inventory parts QDX assembly Rev 1.00...
- Page 13 56pF Through-hole, label “56J” C10, 28 82pF Through-hole, label “820” 1200pF Through-hole, label “122” 820pF Through-hole, label “821” C13, 18 180pF Through-hole, label “181” 22pF Through-hole, label “220” 220pF Through-hole, label “221” 30pF Through-hole, label “300” QDX assembly Rev 1.00...
- Page 14 The white stripe end must be aligned with the white stripe on the image on the PCB silkscreen. In the diagram below, all the white strip ends of the diodes are on the left of each diode position. So far, the assembly should look like this → QDX assembly Rev 1.00...
- Page 15 Install the transistors in the positions shown, with their flat faces flush against the PCB. Use the 12mm M3 bolt, washer and nut to firmly press the transistor faces against the PCB, as shown. Refer to the diagram and photographs below. QDX assembly Rev 1.00...
- Page 16 (Photo, below left). Next, slide the TCXO module onto the wires and lower it to sit flat on the main QDX PCB. Solder the wires carefully and quickly – the TCXO PCB is only a single sided board so the pads will not withstand a lot of heat or abuse –...
- Page 17 Step 3: Now pass the wire through the top hole of the binocular core, back from left to right. This is the next half-turn of the primary winding, bringing the number of turns so far to 1.5; now we must make the center tap. QDX assembly Rev 1.00...
- Page 18 Now we have three turns on the secondary. Cut the wire leaving about 1cm spare. QDX assembly Rev 1.00...
- Page 19 Do this for the 4 winding ends first, leave the two center-tap for later, to make it easier. Step 13: Cut each of the four wire-endings, leaving about 2mm or less, sticking up from the PCB. QDX assembly Rev 1.00...
- Page 20 My cheap DMM hasn’t got a continuity mode and I’m using the 2000-ohm resistance mode; in this mode when there is continuity, the reading on mine shows 001 (not zero- ohms; this is just a DMM thing, of no significance). QDX assembly Rev 1.00...
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