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Kenwood TH-225A

KENWOOD TH-225A handheld transceiver out-of-band modification:

1. Remove the power and antenna
2. Remove 4 screws from back of panel
3. Carefully lift the front panel from the radio. Do not disconnect the flex ca
4. Locate set of 4 jumpers:
5. CUT jumpers J1 and J2.
6. Reassemble the radio.
7. Reset microprocessor: Turn radio on while simultaneously pressing
both _F_ key and _ENTER_ key .


                                                                          AUDIO

I'VE GOT A FIX FOR ANY OF YOU THAT HAVE TH-225A'S.
THE SYMTOMS, NO AUDIO BUT THE KEYPAD BEEP WORKS.
WEAK OR VERY LOW AUDIO. S METER WORKS ON THE NATIONAL WEATHER
SERVICE OR OTHER STRONG SIGNAL SOURCES. ALSO COMPUTER
CLOCK OR HASH NOISE CAN BE HEARD IN THE SPEAKER AT LOW VOLUME.
OPENING UP THE UNIT I FOUND THAT THE VOLUME POT (VR4) PHENOLIC
WAS BROKEN DUE TO A DROP OR HIT ON THE VOLUME CONTROL.

I HOPE THAT THIS WILL HELP ANY OF YOU WITH PROBLEMS
WITH THE TH-225A. GOOD LUCK !!!
TH-225.MOD

HELLO FELLOW HAMS:

I'VE GOT A FIX FOR ANY OF YOU THAT HAVE TH-225A'S.
THE SYMPTOMS, NO AUDIO BUT THE KEYPAD BEEP WORKS.
WEAK OR VERY LOW AUDIO. S METER WORKS ON THE NATIONAL WEATHER
SERVICE OR OTHER STRONG SIGNAL SOURCES. ALSO COMPUTER
CLOCK OR HASH NOISE CAN BE HEARD IN THE SPEAKER AT LOW VOLUME.
OPENING UP THE UNIT I FOUND THAT THE VOLUME POT (VR4) PHENOLIC
WAS BROKEN DUE TO A DROP OR HIT ON THE VOLUME CONTROL.

I HOPE THAT THIS WILL HELP ANY OF YOU WITH PROBLEMS
WITH THE TH-225A. GOOD LUCK !!!
TH-225.MOD


144 - 165 TX/RX MOD
______________________________________________________________________________

TO OPEN YOUR TH-205,215,OR 225 ALL YOU HAVE TO DO IS TAKE OUT THE SCREWS 
ON THE BACK AND GENTLY OPEN UP THE FRONT OF THE UNIT.

LOCATE THE OBVIOUS 4 JUMPER BRIDGES ON THE PC BOARD. 
THE BRIDGES ARE NUMBERED J-1, J-2, J-3, AND J-4..JUMPER J-3 HAS ALREADY BEEN 
CUT...CAREFULLY SNIP JUMPERS J-1 AND J-2 AND EVER SO SLIGHTLY SEPARATE THE 
SNIPPED BRIDGES TO INSURE NO-CONTACT BETWEEN THE POINTS. 

REASSEMBLE THE UNIT. LOOK AT YOUR INSTRUCTION MANUAL AND RESET THE 
MICROPROCESSOR. THE MOD WILL NOT WORK UNTIL YOU RESET THE MPU... 

THE INFO FOR RESET IS NEAR THE BACK OF THE MANUAL. AFTER THAT THE 
UNIT IS WIDE OPEN TO OPERATE BETWEEN 144 TO 165...GOOD LUCK !!!

Again I hope this helps you out !!!

 

Remember it is Illegal to transmit out of band. This Modification is for Informational purposes ONLY.
Doing such modifications on your radio may void any warranty and damage your equipment.
All mods found on this database are offered to me by other amateur radio hams or captured by Packet system. 
KB2LJJ  take no responsibility or liability for any damage done resulting from any modification.  

 I have been trying to help our ham radio with the radio modifications and have asked for any type of new radio mods.
 However, I haven't received too many.  If all of you contributed a little more,  I believe I would be able to help 
all the other ham's that are looking for these mods. I know it is possible to get more mods from all the Ham's because of
 the wide range that exist throughout the world.  By doing this we can  flourish and enjoy more of this hobby that 
we've taken part in for so many years. Furthermore, I ask you not to forget to send me any modifications that you might
 have through email.  I would really appreciate it.

      Email                webmaster@kb2ljj.com

 73's
   John Ribeiro
             KB2LJJ