| Author |
Message |
    
Ham_newbie
New member
Username: Ham_newbie
Post Number: 1
Registered: 11-2005
| | Posted on Sunday, November 20, 2005 - 12:34 am: | 
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I have an older RCI 2950, about 10 years old. The problem I have with it is that it loses TX. It has talk back and a connex echo board installed. When I key down I can hear myself on the talk back, the light on the display changes from RX to TX, but the meter on the left doesn't light up and no one can hear me. Then out of the blue it will start to work again. The receive on the radio is not affected, I can hear others talk no problem. Am I looking at a loose connection or bad relay or something? Thanks for the help if you can. |
Rippedradio
Intermediate Member
Username: Rippedradio
Post Number: 125
Registered: 7-2002
| | Posted on Sunday, November 20, 2005 - 5:13 pm: |
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there is an 8 volt regulator attached to the right side of the radio the very first ic you see on the right side with the speaker side up! this regulator controls the rx and tx and the solder joints become loose over time from mobile use or rough handling! remove the solder from the ic and resolder it to the board with fresh solder! should fix your problem! |
Ham_newbie
New member
Username: Ham_newbie
Post Number: 2
Registered: 11-2005
| | Posted on Sunday, November 20, 2005 - 7:56 pm: |
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Thanks for the help. I will try that. I looked the board over and did not see any loose solder joints, but that doesn't mean there aren't any. |
Inspector
Intermediate Member
Username: Inspector
Post Number: 150
Registered: 12-2001
| | Posted on Thursday, November 24, 2005 - 3:30 am: |
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You Could also have a thermally-intermitant driver or final. |
Kid_vicious
Advanced Member
Username: Kid_vicious
Post Number: 876
Registered: 9-2004
| | Posted on Thursday, November 24, 2005 - 9:49 pm: |
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i agree with both possibilities. the loose connection on the reg. is very common in radios that were used in a mobile for a long period of time. it may be a broken foil trace too. look near the screws that hold the PC board to the metal chassis.
inspector, i just replaced a thermally intermittant driver in a radio of mine, and it blew in a way that i had not seen before. it would work, then not work, then work, then not work. each time for about one or two seconds.
so, HN, i think you have two areas to check, and when replacing the final, remember to be wary of bogus 2SC1969 transistors, they look the same but dont act the same. if you are paying less than $10 for it, then its probably a fake.
also, if you replace the voltage regulator, replace it with a higher rated part. i use a 2SB817 which is a 100watt 12amp device. this will make the radio work much better than the old part.
also replace the 2SA473 with an NTE153 and you will have much clearer modulation.
these are not hacks, these are upgrades. you will like 'em!
good luck,
matt |
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