_________________________________________________________________ From the shack of Paul MacDonald! Packet Radio: WA1OMM@KB4N.NH.USA Modification Instructions for the IC-W2A Handheld Two mods, one for Cross Band Repeat and one for extended TX range Cross Band Repeat Function To access the cross-band repeat function, first perform the extended receive mod by holding down the Light/B/# keys while turning on the power. To enable cross-band repeat, set each band to the frequency and mode desired. Set the current band to VHF. Press (Function-2) (Function-Enter) and the little "L" indicator will flash. The radio is now in the cross-band repeat mode. Do disable, press (Function-Enter) again. Extended Transmit Mod Call the ICOM parts department ((206) 454-8155) and order a pair of MA133 diodes (P/N 1790000850). These are the three terminal surface mount diode packages. It is probably not advisable to substitute conventional leaded glass diodes here due to size restraints. The modification involves removing one surface mount component and installing two others. The working parts are extremely small and the mod should not be performed unless you are comfortable with working while using a loop eyepiece or other magnifying device. This is a "surgical" operation. Take all the usual precautions with respect to static electricity, etc. Remove 5 screws holding back on, and two screws on side of case below the PTT switch. Gently pry the unit apart. Inside the unit are two RF "stack" units. The complete RF "stack" is composed of two enclosed sheet metal boxes sandwiched together, about 1.5" wide, 2" tall and .5" thick. Each RF stack unit (one per band) is totally self contained, is about .25" thick, and plugs into the "motherboard" using connectors mounted on one end. First, remove the stack units. To do this, remove one screw from each side of the stack. Remove the single screw off the bottom end of the stack and gently remove the metal spring clip holding the stack together. Carefully lift each stack unit out by pulling it back and down. They should easily unplug from the upper motherboard. Set them aside for now. At this time the back side of the front panel is clearly accessible and the two CPU's are visible side-by-side across the top. Now refer to the following illustration: Top of Radio, Back side of Front Panel _____________________________________________________ | -------- -------- | | | | | |--- | CPU-1 | | CPU-2 | | | | | | | | P | -------- -------- | T | | T | -------- | | -------- |--- .<: <-D1 ---------- | .. | |fuse | | | D2-> V ---------- | .. | D3-> V | .. | V <-D? | | D1, D2 and D3 are locations on the board. Only D2 is installed at the factory. To perform the mod, you must do the following: Remove D2 Install D1 Install D3 The locations of D1 and D3 are clearly silk screened onto the circuit board and are easy to locate. Don't attempt to re-use D2. The periods (..) show the approximate location of the solder pads for the 2-legged sides of the diodes. Diode D2 may be removed by carefully heating the leads and prying it up using a sharp tool. Be very careful since it's easy to lift the solder pads. One method of installing diodes D1 and D3 is to use a very small drop of super glue to mount the part, and then use a soldering iron to tack down the pins. After the parts are installed, reassemble the radio. Although the manufacturer recommends that the microprocessor be reset after this mod, I have found it to be unnecessary. All memories retained their settings after the mod. Tests using a dummy load and a frequency counter showed TX ability on UHF from under 400MHz to over 490MHz. TX on VHF covers from 136MHz to 174MHz. -fred AA7BQ -- | Fred Lloyd AA7BQ Fred.Lloyd@West.sun.com | | Sun Microsystems, Inc. ...sun!flloyd | | Phoenix, AZ (reality -- what a concept!) (602) 275-4242 | ________________ Now for the added part - multi-digit entry for mhz After doing the above, REQUIRED!! select the VHF band as MAIN push F (above the PTT button) and SET (the 8 button) then using the ^/SCAN button make the lower right symbol of the band say PL rotate the right knob to set the display to 1,10, or 100 as desired 1 sets entry to single digits only 10 sets entry to 10's and single digits 100 sets entry to all digits hit PTT Now - repeat the above for the UHF band - Note It WILL NOT work unless you do it for BOTH bands. You now have a walkie that requires all the digits (assuming you chose 100) to program it's frequencies. /s/ Bob Gettys N1BRM ________________