XTBR Assembly Notes
Preliminary 12/29/09
Please check for the latest version before beginning assembly.
The XTBR has a densely populated circuit board. Assembly requires experience working with small components, and also the ability to correctly identify component values. A low-wattage soldering iron with a 1/16" tip is recommended. Care must be taken to not overheat the semiconductor devices.
BEFORE ASSEMBLY
DO NOT MIX UP THE COMPONENTS. A few people have had trouble identifying components. The zener diode has been packaged with the other semiconductors to help identify it. It is best to keep it packaged until you are ready to install it. You will need a magnifier to read the some of the part numbers. Be sure you have correctly identified ALL the diodes before you begin installing them. I also recommend sorting out the capacitors and resistors before soldering any onto the board. Be careful to correctly identify the 10K and 47K 5% resistors (orange 3rd band). The 1% resistors and the small 220uH inductor may be blue, so be careful identifying them.
PRINTED CIRCUIT BOARD ASSEMBLY:
Please read these Detailed Assembly Instructions before beginning actual assembly to avoid any problems. Also, please refer to the parts list, board layout, and high resolution photograph of the assembled board while assembling your own unit:
Do not try to assemble the XTBR with a high wattage soldering iron having a tip larger than 1/8". A variable temperature iron with a 1/16" tip works well. I recommend installing all diodes and resistors that mount flush to the board first, followed by the DIP socket and other low-profile devices, such as U1. Many components stand on end to save space. Work your way up to larger and larger components. Leave the transformer, large capacitor, and LED for last. The XTBR Board Photograph shows the board before the large components are mounted.
Things to watch out for:
1) The small 220uH inductor L5 looks like a resistor. It can be identified with an ohmmeter because its resistance is about 5 ohms. All resistors are 10 ohms and up.
2) C9 is a polarized tantalum capacitor. Be very careful to get the polarity correct. The positive (+) lead is marked "+", and may also have a long vertical line.
3) There is not much clearance underneath the board. To leave room for the receptacle ground lug, all pins in that area must be clipped flush with the board. This includes the U3 socket, C14, D1, D6, R2, R3, R12, and R14.
4) The PCB can accept several different power transformers, and there are pads for jumpers needed when not using the standard transformer. These pads will not normally be connected. Depending on the transformer manufacturer, the pin numbers may be labeled on the bobbin near the pins, or there may be a mark at pin 1. Verify the transformer is oriented with pin 1 near the MOV before soldering it down.
5) The LED is mounted full-length with sleeving over both pins. The parts kit should contain a 2" length of clear sleeving. Cut that exactly in half and trim slightly so the shortest lead extends just through the circuit board. The longest lead goes into the + pad. If the cover isn't pre-drilled, drill a 7mm hole in the cover 1/2" up from the bottom, and 5/8" in from the side. When the cover is installed, the LED should be bent so it will slip into the red lens snapped into the cover.
6) J2 provides a test point that is checked during electrical test. Do not install a jumper across J2.
RECOMMENDED ASSEMBLY ORDER:
D1, D2, D3, D4 (clip D1 leads flush with the board)D5 (zener)
D6, D7 (clip D6 leads flush with the board)
D8, D9, D10, D11
R5, R6
L5
R13
C6, C7
U1
U3 socket (clip all pins flush with the board)
C3, C4, C13, C14 (clip C14 leads flush with the board)
C10, C11
J2 2-pin header
R3, R2, R12, R14, R9 (clip all leads flush with the board)
R10, R11, R8, R7
NOTE: no 1/4W resistors should be left
C1, C2, C8
C5
MOV (lean toward the edge of the board so it will clear the transformer)
C9 (be sure of polarity)
F1, F2
R1, R4
L1, L2
L3, L4 (mount with narrow end up for best lead clearance)
U2 (small 5V regulator that looks like a transistor)
Q1 (metal tab facing inductors)
C12 (be sure of polarity)
X1 Transformer (pin 1 at corner near the MOV)
D12 LED (cut sleeving in half, insulate leads, mount full height with longer lead at +)
Plug U3 into socket (be sure the notched end faces C14)
XTBR Assembled PCB before installing C12 & transformer X1
INTERWIRING & FINAL ASSEMBLY:
IMPORTANT: The Polycase base must be modified to prevent conflict between the XTBR circuit board and the internal extension of the AC plug ground pin. That extension will be removed from bases shipped with XTBR kits. If your base has not been modified, use a rotary tool with a small cutoff disc to remove the internal extension of the ground pin so that it is flush with the plastic base. It was impossible to create a layout that provided enough clearance so the ground pin extension did not have to be removed. I don't know why Polycase did this, as it is clearly not required for any mechanical reason.
The AC receptacle should be pressed into the opening in the Polycase cover with the same alignment as the plug on the base. The receptacle may not lock in securely unless a screwdriver is used to force the plastic tabs slightly outward until they click into place. Also, press the red LED lens into the hole in the cover. Sometimes it is a tight fit. If so, the hole can be enlarged slightly with a file.
Six connections go to the AC sockets. The 6" green wire supplied with the kit will run directly between the ground pin on the plug and the ground pin on the socket. While not necessary for proper operation, this connection should be installed for safety. The parts kit should include short pieces of 1/8 and 3/16 shrink sleeving to keep the ground tab isolated from the printed circuit board. Connect the green wire to the plug ground tab, and double insulate the tab with the shrink sleeving. It helps to flatten the shrink sleeving by pressing down on it while it is still hot. Keeping the ground tab flush with the plastic base, the ground wire should be routed to the side of the case where it will come up through the notch cut into the edge of the board.
Cut the white wire into 3" and 6" lengths. Cut the black wire into 5 1/2" and 6 1/2" lengths. Strip 1/8" from one end, and 1/4" from the other end of each of these wires. Tin only the longer end because the connections to the PCB may be a tight fit. The short end of each wire is soldered to the printed circuit board as follows:
3" white at the right COM hole near the large capacitor ground lead
6" white at the left COM hole near the large capacitor ground lead
5 1/2" black at AC hole near L1
6 1/2" black at X10 hole near L2
Make sure all leads are cut very close to the circuit board, especially in the area around U3 to provide maximum clearance for the ground tab when the printed circuit board is mounted. The board mounts to the base with 4 short screws. The double insulated portion of the ground lead will be compressed slightly when board is mounted, but that portion of the circuit board contains no solder connections. Make sure the ground lead itself is routed off to the side and up through the notch at the edge of the board.
After the board is mounted, the AC connections are made as follows:
6" green ground wire to the AC receptacle ground tab3" white wire from COM to the AC plug prong near the power FET
5 1/2" black wire from AC to the AC plug prong near the LED
6" white wire from COM to the AC receptacle wide prong tab
6 1/2" black wire from X10 to the AC receptacle narrow prong tab
Check the AC & X10 connections because the XTBR will not work if they are reversed.
XTBR Interconnections
Bend the LED so that it will slip into the lens when the cover is attached. Carefully push excess wire going to the AC receptacle into the free space inside the cover, and attach the cover with the 4 black self tapping screws.
Add the 24 watt warning label to the cover just above the receptacle, and the XTBR label to the recessed portion on the back.
TEST & OPERATION:
As a final check before applying power, verify the resistance between the two plug prongs is about 160 ohms. If it reads much lower, the transformer may have been installed backwards.
Once assembled, plug it into an AC outlet with a manual X10 controller plugged into the receptacle for testing. The LED should flash once when initially plugged in, and whenever the XTBR is receiving or transmitting a command. The LED will not be illuminated all the time like the one on the TW523/PSC05. The LED will also flash in several different patterns to indicate an error. Continuous rapid flashing indicates the XTBR transmitter has shut down due to excess powerline traffic. Please see the XTBR Mode Options document for more information. If the LED does not flash at all, then it is likely something is wired wrong.
The X10 input receptacle on the XTB is rated for 24 watts resistive. More than one device plugged into it will degrade the return signal level. It is important not to exceed the 24-watt limit to prevent damage to internal components. While a typical X10 transmitter consumes less than 3 watts, its load is reactive. To remain safely within the rating, no more than two X10 transmitter loads should be powered by the XTB. The board contains a 3/8A Pico fuse F2 that will pop if the 24 watt limit is exceeded by even a small amount. That should never happen when the XTBR is used for its intended purpose. Obviously, the cause of the fault should be found if either of the fuses must be replaced. While not recommended, a popped Pico fuse could be replaced by a single fine strand of wire from a length #18 flexible lamp cord. To offer protection, that #18 lamp cord should have at least 40 fine strands of wire. Form that into a loop away from the printed circuit board before soldering. X10 modules use a similar inexpensive wire loop for protection.
Please contact me if you have any questions at: jeff@jvde.us
If you don't receive a response within 24 hours, try: xtbjeff@gmail.com
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