| Author |
Message |
    
Thunderbolt
Junior Member
Username: Thunderbolt
Post Number: 34
Registered: 1-2002
| | Posted on Sunday, February 29, 2004 - 9:41 am: | 
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No TX,No RX and TR23 gets very hot. I have tried all I can think of. Replaced TR23,Replaced the TA7222AP IC,Replaced C119,C67,Three legged IC on side of case, both driver and final and a few other can not remember. I am stumped now. I do know some mods were done including something which runs off 12 volts and has one wire conected to C94. I unhooked that. Also TR24 was removed for some reason. I reinstalled it. So,now what? |
Tech8541
Moderator
Username: Tech8541
Post Number: 107
Registered: 12-2003
| | Posted on Sunday, February 29, 2004 - 5:49 pm: |
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the 1st thing i would check is r103 (2w; 200ohm) and d21. they are near tr23. if they go bad, you will have this symptom. |
Thunderbolt
Junior Member
Username: Thunderbolt
Post Number: 35
Registered: 1-2002
| | Posted on Sunday, February 29, 2004 - 6:46 pm: |
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well,I replaced both of those and still does not work. I am pulling the parts from a 29 that is working from the same year. I failed to mention that the channel selector lights dont work or the RX/TX light. Dont know if the two are related or not. |
Tech8541
Moderator
Username: Tech8541
Post Number: 109
Registered: 12-2003
| | Posted on Sunday, February 29, 2004 - 10:08 pm: |
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yes, it is related. tr23 is the main 8v reg, if it is not working then those lights and ch.selector will not work.
you must have something shorted somewhere down the line which is pulling excessive current through tr23 causing it to get hot. what voltages are you getting on the 3 legs of tr23? |
Crafter
Advanced Member
Username: Crafter
Post Number: 940
Registered: 12-2002
| | Posted on Monday, March 01, 2004 - 1:17 am: |
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Thunderbolt have you changed the black transistor just hanging there in a group of wire's cant remeber the number but it works channel led. |
Thunderbolt
Junior Member
Username: Thunderbolt
Post Number: 36
Registered: 1-2002
| | Posted on Sunday, March 07, 2004 - 3:07 pm: |
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I am getting 2 volts between 1rst leg and middle leg and 3 volts between middle leg and 3rd leg.
Crafter,I do not see any transistor that is just hanging in a group of wires. Dont normally see stuff like that in a radio unless its soldered to the board somewhere or bolted to the chassis.The only 3 legged transistor that has wires going to it is bolted to the chassis near the driver. I have changed that.
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tech8541 replies;
I need each legs actual voltage if you can do that. |
