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Redneckinoregon
New member
Username: Redneckinoregon

Post Number: 2
Registered: 3-2004
Posted on Wednesday, March 17, 2004 - 5:19 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have an old style RCI-2970. When the radio gets warm and I turn it on, it will NOT receive or transmit. I have to turn it on and off repeatedly and quickly for it start working properly again. I have been through this radio and cannt figure out what it is. Cold solder? Any suggestions?
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Jon666
Intermediate Member
Username: Jon666

Post Number: 123
Registered: 11-2003
Posted on Wednesday, March 17, 2004 - 5:51 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

sounds like the cpu is going south.
but im no tech.
i would wait for a tech to reply.
good luck with the radio
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Kc0gxz
Advanced Member
Username: Kc0gxz

Post Number: 643
Registered: 3-2003
Posted on Thursday, March 18, 2004 - 3:36 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Redneckinoregon

Cold solder joint? You're close. More than likely it's a "broken" solder joint. But bare in mind that this is just a possibility. I have performed this "fix" many times over the years in my shop.

On the older RCI 2950/70 radios, the metal fram-work of the radio chassis will sometimes bow outwards ever so slightly when mounted in the bracket and the thumb screws are tightend up too much. This pulling force is more than the solder connections can handle and they sometimes pull apart. The voltage regulators on the right-hand side of the 2950/70 are particularly vulnerable, since they are right alongside the mounting-screw bushings. They will receive a greater "pull" on them than the parts nearer the rear of the radio.

Try this simple fix... Replace or resolder the 8 Volt regulator (it looks like a power transistor) that is bolted near the center of the chassis where the mounting screws are. If you decide to install a new one, leave the componet legs long enough to put a small "bow" in them and then solder them to the board. This "bowing" will allow the legs of the regulator to "flex" a bit while bolting the radio back into the bracket.

This was not an uncommon problem with the early RCI 2950s and 70s. Even though, I still would take one of these any day over the new DX models. The older ones are by far much easier to repair.

Good luck and let me know if this was indeed the problem. If not, we'll try something else.

Jeff, kc0gxz.
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Redneckinoregon
New member
Username: Redneckinoregon

Post Number: 3
Registered: 3-2004
Posted on Thursday, March 18, 2004 - 11:14 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thank you!!! I will give this a try when I get home tonight.
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Kc0gxz
Advanced Member
Username: Kc0gxz

Post Number: 649
Registered: 3-2003
Posted on Friday, March 19, 2004 - 9:54 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Redneck

Here's something I forgot to mention.

This occurence rarely happenes when the radio is not mounted in its bracket because there is no strain on the frame.

When you get it hooked up on the bench with the top and bottom covers off and the radio turned ON, grab hold of the sides and pull outwards on them. Doing so will sometimes make the radio shut down. If the radio does indeed shut itself down, then you will know for sure that the problem is what was described above.

Good luck with this project Redneck.

Jeff, kc0gxz.
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Sledgehammer
Junior Member
Username: Sledgehammer

Post Number: 19
Registered: 12-2003
Posted on Friday, April 02, 2004 - 4:40 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have this happening right now to my rci-2950. But, it has never been in it's mounting bracket ever. Once it has been talking I will loose recieve and when I key up I only get the little TX lettering in the display without any transmitting. If I shut it down for approx. 1/2 hour it will work fine again. There is no consistency to this failure either, sometimes I can talk all day and have no problems and other times all it takes is 15 mins. Rf output plays no role from my experience.

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