There are old RCI's with the red displays, (three generations of these to be exact).
Version 1 has the onboard battery for the memory and has to switch from CB band to frequencies by using the LOCK button.
The second generation unit will have the battery eliminated, and still has the large capacitor right in the way of the bracket knob mounting hole on the right side, problem there is someone gets aftermarket knobs and they are too long and bend the cap over till it shorts out or breaks the solder loose on the board. This radio is also where they began using the MAN button to change from CB mode to frequency mode.
The third generation they fixed a few of the interior flaws, such as the large capacitor problem.
Then the modifiable 2950dx, and the "Blue Dot" 2950dx which is the non modifiable version.
Easiest way of identification on these is the green display and they actually say 2950DX right on them.
The DX is also modifiable to seven megs, play around with the jumper settings, you will be amazed what this radio appears to be able to do. I have yet to put a 40 meter capable antenna on this unit to see if it actually works there or not, I do know that it keys there and seems to pick up static there too.
Have a good day and hear from you later.
Larry
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Here is the Mod Info Larry sent me, remember what he said,it is not for the poor solderer, unless you want ot ruin your radio.
RCI 2900 DX Series (Blue Dot Version) , First Generation DX
Modification of “blue dot” unit is possible with “E-Chip” sold separately. Unfortunately, color-coding is not possible, as these chips never seem to come with the same color wires on them, so I have given them numbers instead. These instructions are in the simplest of laymen's terms possible so anyone can do them with a steady hand and a good soldering iron.
Turn off power and remove power leads
Remove top and bottom covers, knobs, and faceplate
Remove the 4 screws holding the CPU board to the chassis
Flip radio over so solder side of main board is facing you and back of radio is toward you
Fold CPU board down carefully so it looks somewhat like Image 1
Now, on the right side of the CPU chip count up 5 legs from the bottom, you will know you have the right one as there is no trace going to this leg
If “E-Chip” comes with wires and plug, remove plug and leave wires as long as possible, strip 1/8” of wire ends and tin. If “E-Chip” comes with plug only, unsolder plug and add 3 wires in its place.
With solder side of “E-Chip” facing you as in Image 2 , connection #3 solders to the 5 th leg previously identified in step 6 (This is the most dangerous part, be careful!)
Now, flip the radio over so you can see the same side of the CPU board, still from the back as in Image 1 , but now it will be upside down
Solder connection #2 of the “E-Chip” to the negative side of the 220 capacitor as shown in Image 1
Connection #1 on the “E-Chip” gets soldered in place as in Image 3
Put radio back together, hook up power, and turn it on. Unit is expanded to 24.0000 to 32.0000 mhz
Remove “Blue Dot” from back of radio!