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NUE-PSK Digital Modem Kit Notes
Constructing the modem yourself |
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Here's the latest version of the Kit Manual ... Kit Manual, rev B2
In addition to the guidance given in the Kit Manual, here are a few extra notes that we've collected along the way. These tips should help you get your modem assembled without incident.
The flex cable used for connecting the LCD to the pc board is really short ... there's no room to spare. (We had a heck of a time finding such a 20-wire cable and this was the only size available.) However it will work out just fine if you follow the guidance offered in the manual, and again here. See the photo sequence below illustrating guidance that is guaranteed to be successful.
~ Photo Guide for Attaching LCD to the PC Board ~
(Click on photos for full-sized view)
Insert controls all the way into the pcb ... Be sure you press the encoder, pushbutton, and (especially) the mini potentiometer R13 all the way down flush to the pcb. The pot is the tightest fit. If these are not inserted all the way, and perpendicular to the board, you will have trouble fitting the board into the enclosure.
Orientation of the Select pushbutton ... This is just an extra (important) reminder to orient the pushbutton with the white tabs on the left and right sides (i.e., one of the white tabs will be closest to Q3).
Aluminum LCD standoffs ... Some kits were supplied with aluminum standoffs for attaching the LCD, whereas others' standoffs were nylon. With the aluminum standoffs, you should be care not to screw them down so hard that they cut through the soldermask and touch the close by traces. Doing so could short the signals on the trace to ground (notably the 5V bus) and cause problems. Normally you'll be fine, unless you use extraordinary force to attach the standoffs.
Different LCDs ... Most of the LCDs we provide in the kits have the "normal" black graphics & text on a grey background, with a white LED for a backlight when turned on. However because of LCD shortages from the manufacturer (Crystalfontz), we accepted some alternate LCDs from them in order to be able to make the kits available in a timely manner. Thus some kit customers will receive a blue or yellow background LCD with white letters. When the backlight is on, it actually looks quite attractive, as seen below ...
Piezo not sounding ... This is normal, as the piezo is not currently being used. We added the piezo for a downstream feature (Morse audio output of Tx and Rx characters), which will come along in a future release.
Slight delay when modem turned on for the very first time ... When powering up your modem for the very first time after construction, you may experience a blank screen for perhaps up to 5 seconds. Then the familiar splash screen and normal display operation will be seen. This initial delay is due to the microcontroller initializing the U4 memory device. This occurs only once, and every time thereafter the splash screen will be seen immediately upon applying power.
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Page last updated: Jul7 24, 2008