ELECRAFT K3 HIGH-PERFORMANCE 160 – 6 METER TRANSCEIVER KDVR3 DIGITAL VOICE RECORDER OPTION INSTALLATION INSTRUCTIONS Rev C, February 16, 2012 Copyright © 2012, Elecraft, Inc.
Contents Introduction............................................................................................................................................... 3 Customer Service and Support ............................................................................................................................ 3 Technical Assistance ....................................................................................................................................... 3 Repair / Alignment Service ...
Introduction The KDVR3 Digital Voice Recorder allows you to prerecord voice messages to be transmitted and to record received audio. The KDVR3is contained on a single circuit board that plugs into the main DSP board. This manual describes how install the KDVR3 in your K3. See Digital Voice Recorder (DVR) in your K3 Owner’s Manual for instructions for using the KDVR3. Only a few basic hand tools are needed (see page 5) to perform the installation. No soldering or wiring is required.
Preventing Electrostatic Discharge Damage There is no climate or work location where the components of your K3 are safe from Electrostatic Discharge (ESD) unless you take specific steps to prevent such damage. Many of the components in your K3 can be damaged by static discharges of only a few volts: far too little for you to notice. It is those low-voltage but destructive discharges that easily happen anywhere and under virtually any environmental conditions. ESD damage may not be apparent at first.
Wear a conductive wrist strap with a series 1-megohm resistor. If you do not have a wrist strap, touch a ground briefly before touching any sensitive parts to discharge your body. Do this frequently while you are working. You can collect a destructive static charge on your body just sitting at the work bench. DO NOT attach a ground directly to yourself as this poses a serious shock hazard. Use a grounded anti-static mat on your work bench.
Installation Procedure Removing the Front Panel Assembly Disconnect power and all cables from your K3. Remove the nine screws to free the top cover as shown in Figure 1. After the cover is open, lift it gently to reach the speaker wire connector. Unplug the speaker then set the top cover aside in a safe place. Whenever you remove screws from a panel, if one screw seems too tight to loosen without damaging it, first loosen the other screws then try again.
Remove the screw shown in Figure 3. It is located directly behind the front panel microphone connector. There may be a lock washer under the screw. If so, save it with the screw. Removing the screw ensures the pc boards on the front panel assembly will have adequate clearance when the front panel assembly is removed in a later step. Remove only the screw shown. Leave the other screw in place as shown in the figure. Figure 3. Removing the 2D Screw.
CAUTION: Before continuing on with the next step, be sure you have removed the three top Front Panel Assembly screws shown in Figure 4. You may bend and damage the front panel or shield assemblies if the screws are not removed! Use a screwdriver in the pry tool openings to press back against the circuit board while pushing the lip on the front panel assembly toward the front as shown in Figure 6.
With the three screws removed, the main DSP board is held on to the front panel board by two multi-pin connectors. Slip your finger tips between the boards and pull the main DSP board away from the front panel board to unplug it. A large, thick spacer washer should be lying on the front panel near the hole for the phones jack (see Figure 9). This spacer fits between the phones jack and the back of the front panel board to provide a solid mechanical ground connection when the boards are in place.
Hardware Upgrades The following changes have been implemented in newer K3s to avoid the possibility of shorts or intermittent operation in some K3s. All the hardware needed is supplied with your KDVR3 kit. If you have the KRX3 installed, check the three screws securing the auxiliary DSP board to the main DSP board to see if they are nylon or metal (see Figure 11). A nylon screw was originally used in one location. If the other two are metal, replace them with the 4-40, 1/4” (6.4mm) nylon screws supplied.
Check the VFO B encoder and trim the pins as shown below if they haven’t been trimmed already to ensure they cannot short against the main DSP board. If trimming is needed, remove the encoder to ensure clipped ends don’t get lost in the front panel assembly. To remove the encoder, loosen the set screws and remove the knob, then remove the felt washer and nut and lift the encoder out. You need trim only the five pins shown close to the back of the pc board. Replace the encoder by reversing the process.
Turn the chassis upside down and position the front panel so the pins of P30 and P35 on the bottom of the RF board just begin to engage the connectors on the lower edge of the front panel assembly as shown in Figure 14). Do not fully mate them yet. Figure 14. Mounting the Front Panel Assembly- Mating P30 and P35. Hold the front panel in place against the chassis assembly and turn the unit over to look at the two multipin connectors on the top of the RF board.
Replace the left side panel (with the handle) as follows: Start the seven 4-40 3/16” (4.8 mm) black flat head screws through the panel: three along the bottom, one at the top rear, one at the top front, and one just below the front end of the handle. It is normal to adjust the position of the panels slightly when assembling so the screw holes line up. The cabinet will become structurally sound and rigid when all the panels, including the top and bottom covers, are mounted. Tighten all seven screws.
Using the Digital Voice Recorder Note: You must have MCU firmware version 2.73 or later installed. Hold AF P L AY to start play. The icon will flash quickly. A seconds counter will be displayed on VFO B, along with an asterisk (*) if you’re within the most recently recorded audio segment. Rotating VFO B jumps forwards/backwards through recorded audio. To stop play, tap any button. The KDVR3 option allows you to record and play voice messages as well as capture received audio.
