Cobra 2000GTL frequency adjustment

[sonoma]

with VR5 not working sounds to me like the clarifier had been partially done. but I am not there to look inside to see what has been done.some one may have just done a partial mod to it.

 

[Adamf]

You could be very well right show us some pictures of the inside of the unit maybe someone here can see if the clarifier has been mod.

Thanks guys, that makes sense and I appreciate all you good people trying to help. I will post pictures later today. Thanks! Adam

 

[Adamf]

Thanks guys, that makes sense and I appreciate all you good people trying to help. I will post pictures later today. Thanks! Adam

OK guys, here are pictures. There is a 4 position switch on the back of the radio. 2 wires go to the MB8719, 2 wires go to the clarifier, and a couple of other wires go to some little parts added on the underside of the main board. ALSO, there is a red wire cut just sitting there to the left of the clarifier, you can see it in the pictures. Who can help me resolve this mystery! Thanks, Adam

 

[wavrider]

Some sort of configuration of channel expansion,

 

[Adamf]

Yes, can anyone help me with how to get it back on frequency? Thanks Adam

 

[Adamf]

Yes, can anyone help me with how to get it back on frequency? Thanks Adam

Hi all, I did some more looking and I found a cut brown wire so what I see is that someone did an expansion mod and part of it was running 2 wires from the mod switch to the clarifier but not sure why as the clarifier does not vary the frequency much. Anyway, the red and brown wires were cut from the clarifier and left loose, can anyone help? Thanks, Adam

 

[kaos513]

Hi all, I did some more looking and I found a cut brown wire so what I see is that someone did an expansion mod and part of it was running 2 wires from the mod switch to the clarifier but not sure why as the clarifier does not vary the frequency much. Anyway, the red and brown wires were cut from the clarifier and left loose, can anyone help? Thanks, Adam

Look up channel mod for cobra 2000gtl might match what you see here : http://www.cbtricks.com/pub/secret_cb/vol_07/graphics/secret_cb_vol_07_pg15_17.pdf

 

[kaos513]

Hi all, I did some more looking and I found a cut brown wire so what I see is that someone did an expansion mod and part of it was running 2 wires from the mod switch to the clarifier but not sure why as the clarifier does not vary the frequency much. Anyway, the red and brown wires were cut from the clarifier and left loose, can anyone help? Thanks, Adam

Here is another mod for your cobra 2000gtl try to match what you have have in your radio read here :http://www.cbtricks.com/pub/secret_cb/vol_15/graphics/secret_cb_vol_15_pg25_28.pdf

 

[Adamf]

Here is another mod for your cobra 2000gtl try to match what you have have in your radio read here :http://www.cbtricks.com/pub/secret_cb/vol_15/graphics/secret_cb_vol_15_pg25_28.pdf

Thanks, I have seen that, it did not help but thanks, Adam

 

[kaos513]

Thanks, I have seen that, it did not help but thanks, Adam

Thanks, I have seen that, it did not help but thanks, Adam

Does look like a channel mod here as well

 

[Adamf]

Brown and red has been cut so it looks like above mod could match what you have

Hi, not really because in that mod the red has to go somewhere else so that is not it. Anyway thanks, hopefully someone is familiar with the 2000GTL and can help. Adam

 

[Adamf]

Hi, not really because in that mod the red has to go somewhere else so that is not it. Anyway thanks, hopefully someone is familiar with the 2000GTL and can help. Adam

Hi, yes, it has the channel mod but I need help with the voice lock clarifier so if someone is familiar with the 2000GTL please chime in, thanks again, Adam

 

[kaos513]

Do you get the right frequency when you use an external frequency counter?

 

[Adamf]

Do you get the right frequency when you use an external frequency counter?

Yes, as mentioned in my FIRST post, the external frequency counter matches the Cobra frequency counter, the radio is off frequency. Again, if anyone is familiar with the 2000GTL and can help I would be very grateful, I think between the info I have given and pictures I have posted some one with knowledge of this radio may be able to help. Thanks, Adam

 

[kaos513]

Yes, as mentioned in my FIRST post, the external frequency counter matches the Cobra frequency counter, the radio is off frequency. Again, if anyone is familiar with the 2000GTL and can help I would be very grateful, I think between the info I have given and pictures I have posted some one with knowledge of this radio may be able to help. Thanks, Adam

Try this if you are very familiar with the cobra 2000gtl, Note: at your own risk thanks.


Set the clarifier to center frequency - however you like it to be centered, and then with the radio on RX, adjust these inductors in this order:
L59-USB
L22-LSB
L23-AM

VR5 is to adjust the TX frequency. It adjusts all modes so you should adjust the receive frequencies first, and then adjust VR5 to synchronize transmit.