BAND EXPANSION MODIFICATION FOR IC-02AT FOR SERIAL NUMBERS ABOVE 34000 BY LTC STEVE PETERS, CAP ------------------------------------------------------------------------ 1. Remove back from radio (5 screws) and bottom plate (4 screws). 2. Carefully remove radio chassis from front case by pulling out top of radio and lifting slightly (to remove battery contacts from bottom case). Be extremely careful of ribbon cable and heat sink compound on power amplifier module. 3. Remove diode D2 from matrix board. 4. Add diode D4 (any small diode 1N4148; 1SS211 5. The following is a schematic of the matrix board: ADD D4 REMOVE D2 I--+ --+-- --+-- + V D4 ID3 I ID2 I D1 I I I I I + + +---+ +---+ + + 6. Install radio chassis back into front cover. Leave back off temporarily. 7. Carefully apply power to radio and enter the lowest desired frequency. 8. Adjust slug through bottom hole on VCO corr for .5 VDC at VCO test point (just below VCO shield) at lowest desired operating frequency. 9. This completes the modification. A few words of caution: 1. The radio is not type accepted for use in the commercial band. 2. Make sure you reinstall the battery latch correctly on bottom of radio or battery will become permanently locked onto radio. 3. Tighten screws on bottom of radio snuggly. If they loosen while battery is connected you cannot remove the battery. (This has happened to any units and it would be prudent to periodically check these screws to assure their tightness.) ------------------------------------ ***->Be careful not to transmit out-of-band, or accidentally operate on any non-amateur, unless you are authorized to do so. DO NOT JEOPARDIZE YOUR LICENSE! ============================================================================ Another Icom IC02 Modification =============================================================================== The following method of modifying the Icom IC02 is an alternate to the IC02.MOD file. This one should give you PL out of band without jumpering 5 VDC to the tone chip. Use 1N914 or equivelent when adding diodes. 1. On the logic matrix, remove D402 and D403. 2. Add D402, D403 and D404 with the cathode at 4 o'clock and the anode at 12 o'clock. 3. Retune the VCO to cover your desired frequency spread. My 02AT did not want to go beyond 163 MHz. I have a friend whowas able to get his to the low 170s. 4. To jump from 140 to 150 or from 150 to 160 (or vice versa) you must "tune across" the boundry, in the same way that you do for an unmodified 02AT. For example, key in 149.995 and then move up until you are in the 150s. You can then enter any 150 MHz frequency (starting with the MHz). =============================================================================== ===== AUDIO MODIFICATION FOR ICOM IC02 AND IC04 RADIOS ===== ------------------------------------------------------------------------------ This audio mod works on the 02 and 04AT. It increases the level of audio, as well as rolling off some of the lows. Sounds real nice. It involves the circuit around Q105. 1. Replace C119 with a .01 uF cap (disc ceramic is fine). 2. Parallel R131 with a 1 uF cap (use a tantalum cap). 3. Parallel R132 with a .01 uF cap (disc ceramic is fine). This is not the same mod as the one International Radio is advertising, which involves changing C117. I tried an AB-1 Audiolaster from Engineering Consulting, and was very unhappy with the results. I am very pleased with the audio given by this mod (much cheaper too!). ---------------------------------- [EOF] ***->Be careful not to transmit out-of-band, or accidentally operate on any non-amateur, unless you are authorized to do so. DO NOT JEOPARDIZE YOUR LICENSE! =============================================================================== Msg Nr. : 49374 Da : IW3GRX Per : MOD Tipo/status : PN Data/ora : 0521/2129 Dimensione : 4670 Titolo : Alcune modifiche per l'IC02 Bid (Mid) : 4355_IW3GRW ллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллл BAND EXPANSION MODIFICATION FOR IC-02AT FOR SERIAL NUMBERS ABOVE 34000 BY LTC STEVE PETERS, CAP ------------------------------------------------------------------------ 1. Remove back from radio (5 screws) and bottom plate (4 screws). 2. Carefully remove radio chassis from front case by pulling out top of radio and lifting slightly (to remove battery contacts from bottom case). Be extremely careful of ribbon cable and heat sink compound on power amplifier module. 3. Remove diode D2 from matrix board. 4. Add diode D4 (any small diode 1N4148; 1SS211 5. The following is a schematic of the matrix board: ADD D4 REMOVE D2 I--+ --+-- --+-- + V D4 ID3 I ID2 I D1 I I I I I + + +---+ +---+ + + 6. Install radio chassis back into front cover. Leave back off temporarily. 7. Carefully apply power to radio and enter the lowest desired frequency. 8. Adjust slug through bottom hole on VCO corr for .5 VDC at VCO test point (just below VCO shield) at lowest desired operating frequency. 9. This completes the modification. A few words of caution: 1. The radio is not type accepted for use in the commercial band. 2. Make sure you reinstall the battery latch correctly on bottom of radio or battery will become permanently locked onto radio. 3. Tighten screws on bottom of radio snuggly. If they loosen while battery is connected you cannot remove the battery. (This has happened to any units and it would be prudent to periodically check these screws to assure their tightness.) ------------------------------------ ***->Be careful not to transmit out-of-band, or accidentally operate on any non-amateur, unless you are authorized to do so. DO NOT JEOPARDIZE YOUR LICENSE! [EOF] ллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллл Another Icom IC02 Modification =============================================================================== The following method of modifying the Icom IC02 is an alternate to the IC02.MOD file. This one should give you PL out of band without jumpering 5 VDC to the tone chip. Use 1N914 or equivelent when adding diodes. 1. On the logic matrix, remove D402 and D403. 2. Add D402, D403 and D404 with the cathode at 4 o'clock and the anode at 12 o'clock. 3. Retune the VCO to cover your desired frequency spread. My 02AT did not want to go beyond 163 MHz. I have a friend whowas able to get his to the low 170s. 4. To jump from 140 to 150 or from 150 to 160 (or vice versa) you must "tune across" the boundry, in the same way that you do for an unmodified 02AT. For example, key in 149.995 and then move up until you are in the 150s. You can then enter any 150 MHz frequency (starting with the MHz). ----------------------------- ***->Be careful not to transmit out-of-band, or accidentally operate on any non-amateur, unless you are authorized to do so. DO NOT JEOPARDIZE YOUR LICENSE! [EOF] ллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллл ===== AUDIO MODIFICATION FOR ICOM IC02 AND IC04 RADIOS ===== ------------------------------------------------------------------------------ This audio mod works on the 02 and 04AT. It increases the level of audio, as well as rolling off some of the lows. Sounds real nice. It involves the circuit around Q105. 1. Replace C119 with a .01 uF cap (disc ceramic is fine). 2. Parallel R131 with a 1 uF cap (use a tantalum cap). 3. Parallel R132 with a .01 uF cap (disc ceramic is fine). This is not the same mod as the one International Radio is advertising, which involves changing C117. I tried an AB-1 Audiolaster from Engineering Consulting, and was very unhappy with the results. I am very pleased with the audio given by this mod (much cheaper too!). ---------------------------------- [EOF] ллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллллл Msg Nr. : 154583 Da : IW3GRX Per : TMP Tipo/status : PN Data/ora : 0219/1756 Dimensione : 7033 Bid (Mid) : 23511_IW3GRX Titolo : Alcune modifiche per l'IC02 **************************************************************************** Subject: BAND EXPANSION MODIFICATION FOR IC-02AT FOR SERIAL NUMBERS ABOVE 34000 BY LTC STEVE PETERS, CAP ------------------------------------------------------------------------ 1. Remove back from radio (5 screws) and bottom plate (4 screws). 2. Carefully remove radio chassis from front case by pulling out top of radio and lifting slightly (to remove battery contacts from bottom case). Be extremely careful of ribbon cable and heat sink compound on power amplifier module. 3. Remove diode D2 from matrix board. 4. Add diode D4 (any small diode 1N4148; 1SS211 5. The following is a schematic of the matrix board: ADD D4 REMOVE D2 I--+ --+-- --+-- + V D4 ID3 I ID2 I D1 I I I I I + + +---+ +---+ + + 6. Install radio chassis back into front cover. Leave back off temporarily. 7. Carefully apply power to radio and enter the lowest desired frequency. 8. Adjust slug through bottom hole on VCO corr for .5 VDC at VCO test point (just below VCO shield) at lowest desired operating frequency. 9. This completes the modification. A few words of caution: 1. The radio is not type accepted for use in the commercial band. 2. Make sure you reinstall the battery latch correctly on bottom of radio or battery will become permanently locked onto radio. 3. Tighten screws on bottom of radio snuggly. If they loosen while battery is connected you cannot remove the battery. (This has happened to any units and it would be prudent to periodically check these screws to assure their tightness.) ------------------------------------ ***->Be careful not to transmit out-of-band, or accidentally operate on any non-amateur, unless you are authorized to do so. DO NOT JEOPARDIZE YOUR LICENSE! [EOF] Copied from the QRZ! Windows Ham Radio CDROM *********************************************************************** Subject: Another Icom IC02 Modification =============================================================================== The following method of modifying the Icom IC02 is an alternate to the IC02.MOD file. This one should give you PL out of band without jumpering 5 VDC to the tone chip. Use 1N914 or equivelent when adding diodes. 1. On the logic matrix, remove D402 and D403. 2. Add D402, D403 and D404 with the cathode at 4 o'clock and the anode at 12 o'clock. 3. Retune the VCO to cover your desired frequency spread. My 02AT did not want to go beyond 163 MHz. I have a friend whowas able to get his to the low 170s. 4. To jump from 140 to 150 or from 150 to 160 (or vice versa) you must "tune across" the boundry, in the same way that you do for an unmodified 02AT. For example, key in 149.995 and then move up until you are in the 150s. You can then enter any 150 MHz frequency (starting with the MHz). ----------------------------- ***->Be careful not to transmit out-of-band, or accidentally operate on any non-amateur, unless you are authorized to do so. DO NOT JEOPARDIZE YOUR LICENSE! [EOF] Copied from the QRZ! Windows Ham Radio CDROM ************************************************************************ Subject: AUDIO MODIFICATION FOR ICOM IC02 AND IC04 RADIOS ===== ------------------------------------------------------------------------------ This audio mod works on the 02 and 04AT. It increases the level of audio, as well as rolling off some of the lows. Sounds real nice. It involves the circuit around Q105. 1. Replace C119 with a .01 uF cap (disc ceramic is fine). 2. Parallel R131 with a 1 uF cap (use a tantalum cap). 3. Parallel R132 with a .01 uF cap (disc ceramic is fine). This is not the same mod as the one International Radio is advertising, which involves changing C117. I tried an AB-1 Audiolaster from Engineering Consulting, and was very unhappy with the results. I am very pleased with the audio given by this mod (much cheaper too!). ---------------------------------- [EOF] Copied from the QRZ! Windows Ham Radio CDROM ************************************************************************ Date: Wednesday, 5 June 1985 From: Russ Schroeder Subject: IC-02A mod Re: Modified PLL rigs The modification to the IC-02A to increase the receiver is fairly straight forward although a little delicate. The programming diodes are located on the board directly behind the front panel, and are located in the corner of the board. They are little rectangular black three leaded devices. The proceedure to modify the radio is as follows: 1) Remove diode D2 - use a very small iron and solder wick to remove most of the solder, then lift the diode GENTLY while heating the single tab side. After getting the first tab free, proceed to the other two tabs, lifting them one at a time. Do NOT use a large iron or too much heat. 2) Take the diode and locate in the position labled D5. Carefully solder the diode in place. 3) Reassemble the radio except for the back. 4) Program the radio to the local weather channel (162.400 or 162.550) in the following manner: 6 2 4 0 0 or 6 2 5 5 0 NOTE: the programming proceedure now requires that you enter the ten's of Mhz when entering a frequency. 5) Look at the back of the radio. In approximately the center of the exposed board is a metal can with two adjustments. The top adjustment is a metal screw (actually a trimmer capacitor) while the bottom adjustment is a black slug with a small rectangular adjusting slot 6) With the squelch open, adjust the lower black core counterclockwise approximately 1 1/4 turns until you receive the weather station. As soon as you receive the weather, STOP turning the adjustment. 7) Replace the back on the radio and you are in business. With this modification, the radio will tune from 140.000 Mhz to something over 162.550 without difficulty. Just remember that you must enter the ten's of Mhz when entering a frequency. This modification does not affect the transmitter which still covers 140.000 to 151.995 Mhz. Please note: This mod does not retune any of the RF stages of the receiver so the sensitivity is down some at the weather frequency, however, I have no difficulty receiving it at thirty to forty miles. I do have the ICOM service manual on the IC-02A. I purchased it from Delaware Amateur Supply at a local hamfest several weeks ago. According to the manual, the VCO on the PLL should cover 25 Mhz. minimum. Good luck. If you hear of any other mods to the IC-02A please let me know. Russ W2DYY Schroeder.HENR@Xerox.ARPA Copied from the QRZ! Windows Ham Radio CDROM *********************************************************************** Msg Nr. : 171315 Da : EA7FHR Per : MODS @WW Tipo/status : BF Data/ora : 0331/1032 Dimensione : 8234 Bid (Mid) : 23587_EA7FKB Titolo : Alcune modifiche per l'IC02 Subject: BAND EXPANSION MODIFICATION FOR IC-02AT FOR SERIAL NUMBERS ABOVE 34000 BY LTC STEVE PETERS, CAP ------------------------------------------------------------------------ 1. Remove back from radio (5 screws) and bottom plate (4 screws). 2. Carefully remove radio chassis from front case by pulling out top of radio and lifting slightly (to remove battery contacts from bottom case). Be extremely careful of ribbon cable and heat sink compound on power amplifier module. 3. Remove diode D2 from matrix board. 4. Add diode D4 (any small diode 1N4148; 1SS211 5. The following is a schematic of the matrix board: ADD D4 REMOVE D2 I--+ --+-- --+-- + V D4 ID3 I ID2 I D1 I I I I I + + +---+ +---+ + + 6. Install radio chassis back into front cover. Leave back off temporarily. 7. Carefully apply power to radio and enter the lowest desired frequency. 8. Adjust slug through bottom hole on VCO corr for .5 VDC at VCO test point (just below VCO shield) at lowest desired operating frequency. 9. This completes the modification. A few words of caution: 1. The radio is not type accepted for use in the commercial band. 2. Make sure you reinstall the battery latch correctly on bottom of radio or battery will become permanently locked onto radio. 3. Tighten screws on bottom of radio snuggly. If they loosen while battery is connected you cannot remove the battery. (This has happened to any units and it would be prudent to periodically check these screws to assure their tightness.) ------------------------------------ ***->Be careful not to transmit out-of-band, or accidentally operate on any non-amateur, unless you are authorized to do so. DO NOT JEOPARDIZE YOUR LICENSE! Date: Wednesday, 5 June 1985 From: Russ Schroeder Subject: IC-02A mod Re: Modified PLL rigs The modification to the IC-02A to increase the receiver is fairly straight forward although a little delicate. The programming diodes are located on the board directly behind the front panel, and are located in the corner of the board. They are little rectangular black three leaded devices. The proceedure to modify the radio is as follows: 1) Remove diode D2 - use a very small iron and solder wick to remove most of the solder, then lift the diode GENTLY while heating the single tab side. After getting the first tab free, proceed to the other two tabs, lifting them one at a time. Do NOT use a large iron or too much heat. 2) Take the diode and locate in the position labled D5. Carefully solder the diode in place. 3) Reassemble the radio except for the back. 4) Program the radio to the local weather channel (162.400 or 162.550) in the following manner: 6 2 4 0 0 or 6 2 5 5 0 NOTE: the programming proceedure now requires that you enter the ten's of Mhz when entering a frequency. 5) Look at the back of the radio. In approximately the center of the exposed board is a metal can with two adjustments. The top adjustment is a metal screw (actually a trimmer capacitor) while the bottom adjustment is a black slug with a small rectangular adjusting slot 6) With the squelch open, adjust the lower black core counterclockwise approximately 1 1/4 turns until you receive the weather station. As soon as you receive the weather, STOP turning the adjustment. 7) Replace the back on the radio and you are in business. With this modification, the radio will tune from 140.000 Mhz to something over 162.550 without difficulty. Just remember that you must enter the ten's of Mhz when entering a frequency. This modification does not affect the transmitter which still covers 140.000 to 151.995 Mhz. Please note: This mod does not retune any of the RF stages of the receiver so the sensitivity is down some at the weather frequency, however, I have no difficulty receiving it at thirty to forty miles. I do have the ICOM service manual on the IC-02A. I purchased it from Delaware Amateur Supply at a local hamfest several weeks ago. According to the manual, the VCO on the PLL should cover 25 Mhz. minimum. Good luck. If you hear of any other mods to the IC-02A please let me know. Russ W2DYY Schroeder.HENR@Xerox.ARPA Copied from the QRZ! Windows Ham Radio CDROM Subject: Another Icom IC02 Modification =============================================================================== The following method of modifying the Icom IC02 is an alternate to the IC02.MOD file. This one should give you PL out of band without jumpering 5 VDC to the tone chip. Use 1N914 or equivelent when adding diodes. 1. On the logic matrix, remove D402 and D403. 2. Add D402, D403 and D404 with the cathode at 4 o'clock and the anode at 12 o'clock. 3. Retune the VCO to cover your desired frequency spread. My 02AT did not want to go beyond 163 MHz. I have a friend whowas able to get his to the low 170s. 4. To jump from 140 to 150 or from 150 to 160 (or vice versa) you must "tune across" the boundry, in the same way that you do for an unmodified 02AT. For example, key in 149.995 and then move up until you are in the 150s. You can then enter any 150 MHz frequency (starting with the MHz). ----------------------------- Subject: AUDIO MODIFICATION FOR ICOM IC02 AND IC04 RADIOS ===== ------------------------------------------------------------------------------ This audio mod works on the 02 and 04AT. It increases the level of audio, as well as rolling off some of the lows. Sounds real nice. It involves the circuit around Q105. 1. Replace C119 with a .01 uF cap (disc ceramic is fine). 2. Parallel R131 with a 1 uF cap (use a tantalum cap). 3. Parallel R132 with a .01 uF cap (disc ceramic is fine). This is not the same mod as the one International Radio is advertising, which involves changing C117. I tried an AB-1 Audiolaster from Engineering Consulting, and was very unhappy with the results. I am very pleased with the audio given by this mod (much cheaper too!). ---------------------------------- 73s de Jeronimo EA7FHR @EA7FKB.EAAL.ESP.EU. P.O.BOX: 322 04080 ALMERIA