Cobra 89xlr

[Ben Hebert]

It hasn't had the d14 mod yet as I can tell. Should I do the upgrade and replace the transistor to rule that out?

 

[sonoma]

if it has not been done I would do it to make sure that is not what is causing you a problem. it said it kills TX and RX if it shorts the trans out.

 

[Ben Hebert]

I will do it to make sure it's not the problem. It recieves fine just not tx

 

[Ben Hebert]

Any place that sells them other than eBay?

 

[Ben Hebert]

I upgraded the diode just waiting for the transistor to come in. What would cause the channel display not to show channel?

 

[sonoma]

when did the channel display go out. 1st I read about this issue.

 

[Ben Hebert]

When I first recieved the radio didn't work. it worked before he shipped to me

 

[sonoma]

you will need to start checking the voltages to the front end to see where you are losing it. this will keep it from transmitting.

 

[Ben Hebert]

So I should start where the flex point goes to the main board and go from there?

 

[sonoma]

here is the schematic. start at the PA CB switch and make sure you have about 8 volts to both sides of the switch. did you clean the switches as mentioned. why did you just now mention it did not have the leds working. I went back and read all you have posted on it. did you finish with all new electro caps.

 

[Ben Hebert]

Yeah I finished all the caps .it has 12.26 volts on both sides of the switch and the channel have going to the board also

 

[Robb]

Uh oh . . .

 

[Ben Hebert]

What?

 

[sonoma]

do you have about 3 volts going to the 2 middle pins of the readout. should be the bottom pins. need to see where you are losing voltage to the led pins. have you done the D14 mod as of yet. it may be causing you to lose voltage to the front end. I searched the web looking for a voltage chart and could not find one.
does any one here on the forum have a cb124 sams book. this radio is in it. it will have the voltage chart in it.

 

[Ben Hebert]

Which pins exactly? Yeah I did the d14 mod