NHRC-2 User Guide
NHRC-2 Assembly Guide
Page 2
3/16/2000
Copyright © 2000, NHRC LLC
All Rights Reserved.
7. Install the crystal, Y1, being careful not to have the part body contact the trace below it.
Lifting Y1 up slightly off the PCB or using a dab of RTV or “hot glue” under the part
before soldering will solve this.
8. Install pots, VR1, VR3, VR4, VR5 & VR6 which are 10K (marked "103") and VR2
which is 500K (marked "504").
9. Install connector P1, and 2 pin header SW1.
10. Install the chip sockets. (Note: Install them so that designator for pin 1 is per the notch
shown on this chip socket on the silkscreen.) Do not install your chips at this time.
You will need to do some power up checks first.
11. Solder all of your connections using a small soldering iron of approx. 25-40 watts. (DO
NOT USE A SOLDERING GUN). Use a "63/37" rosin flux-core solder and use care not
to overheat the PCB. Carefully trim the leads of the bottom of the PCB. Clean the PCB
to remove flux residue with alcohol. You may also consider using a water-soluble flux-
core solder (such as Alpha Metals Aqualine 6000). A quick rinse under warm water in
your sink after assembly and your finished product will look professional.
12. Double-check your work. Check for any unsoldered parts, solder bridges, or improper
part placement.
You are now ready to apply power to the PCB and check some voltages before installing the IC
chips. See the Users Guide for assistance with assembly of the connections required. Apply
power and check that the +5V regulator is working and that +5 volts (VCC) is being supplied
where needed (Example: U1 pin 14, U2 pins 16 & 28, etc.). Check that VREF is approximately
1/2 of your input supply voltage is at U5 pins 3 & 5. When you are confident that all of your
voltages are OK then you are ready to install your chips. After which you can power the PCB
back up, INIT the processor (following the procedure in the Users Guide) and enjoy!
If you encounter problems go back and recheck your work, look for unsoldered connections,
solder bridges or misplaced components.
Look at the Assembly FAQ and the Troubleshooting Guide included in the Users Guide or visit
the NHRC-2 web site http://www.nhrc.net/nhrc2 for more detailed trouble shooting
instructions. We also offer troubleshooting support by email [email protected]. The circuit
is fairly simple and most problems can be resolved quickly.
Alpha Metals solder info is available at http://www.alphametals.com
