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 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. 73's, -fred AA7BQ ============================================================================== > I've heard of a mod to increase the UHF out of band receive sensitivity of > the W2A. Could anyone please send me or post more information about this. I've got a diagram that shows how to do it but it's not real good at labeling pin numbers so I'll try to describe it. One word of warning. The parts involved here are surface mount and are very tiny. It's very easy to screw something up and loose UHF receive. You need to open up the the UHF unit inside the radio and look at the component side of the board. Q7 is a 5 pin surface mount IC that is near the edge of the board, about a half an inch from the URF unit. There are 2 pins on the side nearest the URF unit. You must lift the one nearest the edge of the board. Most of the people that I know who've tried this have broken off the IC leg or lifted the pad from the circuit board. I don't see Q7 in the schematic, I think it's D7 in there. Q3 is a surface mount transistor thats near the center of the board about three quarters of an inch from the URF unit. Once you've lifted the pin on Q7 you attach the cathode end of a 1N34 diode to it. The anode end of the diode goes to the pin on Q3 that only has one pin on that side. It sounds easy but Q7 is in a very tight corner. Here's an attempt at diagramming the locations. The "<-" mark where the connections should be. ----------------------------------------------------------- Q3 _ ___ |_|<- |L1 | ----------- |___| ---------------- | | VCO | Q7 | UNIT | _ | URF unit | | | | | | | | ----------- |_|<- ---------------- ----------------------------------------------------------- ============================================================================== Subject: IC-W2A multi-digit MHZ entry procedure More stuff on the IC-W2A - Thanks to Paul for this part which is REQUIRED for the next step!! This is less of a mod than it is a function. To expand the receiver frequency range of the new Icom IC-W2A to 118.00-170.00, 322.00-513.00, and 800.000-970.000, do the following: o Hold down the Light, B, and # keys while turning the power on. That's actually a four button sequence, since power on is controlled by a keypad button. 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. ============================================================================== AH the truth of the matter is that if you set PL to 100 you can enter and recieve any frequency between 100MHz and 999MHz, then by rotating the tuning dial you can push the radio beyond the 1GHz mark and keyboard enter all the way to 1.2GHz. Here is the complete Mod....try it for yourself. Hold Down 3 # B Turn power on Hold for 30 seconds Enter Set Mode Use ^/Scan key to select PL Use tuning dial to change the PL Setting as below: PL = 1 range 140.000 to 149.995 PL = 10 range 100.000 to 199.995 PL = 100 range 100.000 to 999.995 note reception above 999.995MHz and below 100.000MHz is possible but very poor selectivity. ============================================================================== For crossband repeat, just set up each band with the mode which you want to use, and then hit 2 ENTER - To cancel hit 2 ENTER again. This is less of a mod than it is a function. To expand the receiver frequency range of the new Icom IC-W2A to 118.00-170.00, 322.00-513.00, and 800.000-970.000, do the following: o Hold down the Light, B, and # keys while turning the power on. That's actually a four button sequence, since power on is controlled by a keypad button. ============================================================================== I saw your message in my BBS SK7DD in the southern part of Sweden. I have a W2E and its modified to recive from 126 MHZ to 999 MHZ with transmiting posibility from 144 MHZ to 146 MHZ (VHF) and 430 MHZ to 440 MHZ (UHF), I know that the W2A can transmit on higher freq becuse you have a lager ham band on both 2M and 70cm. The file below have been sent to me from England, and I hope that you will find it interesting as I did................................ ****************************************************************************** => Display test / Rx Expanding; ---------------------------- Turn the porto off, press the #,3 and the B, hold this buttons, now turn on your porto (Red Button), you will see now all the functions who are in the lcd display. When you quit pressing the #,3 and the B button, your porto can now go (On Display) from 100khz <> 999.90Mhz at the 2m Display, and on the 70cm Display he will go from 100khz <> 1310.00Mhz, of course he will not recieve from 100khz <> 1310Mhz, but the low vfo receive at least from 126Mhz <> 190Mhz, the high vfo receive at least from 390Mhz <> 999Mhz, with some steps between 390Mhz <> 999Mhz where he not receive signals, because the vfo is out of his lock. => Enter Freq via keyboard; ------------------------ When you enter a freq (in vfo mode) by pressing enter (ENT) you will see that you can press only the last 3 digits, this is simply to change by pressing the function button (above the ptt) and the set (8) button, push now with the ^/scan until you see on the display 'PL', now you can dial 1 - 10 -100 = 1Mhz - 10Mhz - 100Mhz, set this option to 100 (dial), now you press the clr (*). Done !!!! If you now press enter (#) (in vfo mode) you will see that you now can press the whole freq. The same for the other vfo, this go's the same for 1Mhz - 10Mhz PL function. => Steps with the dial; -------------------- Dialing a freq go's with steps in Khz, by pressing the function key (above the ptt) the steps will be now steps of 10Mhz. Here are some RX reports by JBE; -------------------------------- RX Freq Sensitivity (12db sinad) ------------------------------------------------- 126MHz - 111dBm 136MHz - 123dBm 145MHz <*** Main ***> - 125dBm 160MHz - 123dBm 174MHz - 110dBm 190MHz - 67dBm Low vfo ------------------------------------------------- 390MHz - 108dBm 430MHz <*** Main ****> - 124dBm 452MHz - 105dBm 470MHz - 103dBm 485MHz - 104dBm 850MHz - 110dBm 900MHz - 116dBm 925MHz - 114dBm 935MHz - 112dBm 950MHz - 107dBm 999MHz - 96dBm Hi vfo -------------------------------------------------