[Solved] Cobra 146 GTL Clarifier Unlock. Did I do it right?

[doffo]

Hello,

For whatever reason, it seemed like it was hard to find any pictures or at least some better visuals on how to do the clarifier. I did it the best I could, and attached the pictures.
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Thanks to Nomad for the help on going about the modification.

 

[nomadradio]

Nope.

Gotta remove the transmit-only voltage source. Either pull D32 or VR3. Either one will break the transmit-side circuit. Until you do this, the radio will never transmit and receive on the same frequency.

R122 is there to make sure that D31 or D32 turns on all the way. There has to be SOME current through a diode to use it as a switch. The varactor diode alone won't draw any DC current, so R122 takes care of that.

73

 

[doffo]

Nope.

Gotta remove the transmit-only voltage source. Either pull D32 or VR3. Either one will break the transmit-side circuit. Until you do this, the radio will never transmit and receive on the same frequency.

R122 is there to make sure that D31 or D32 turns on all the way. There has to be SOME current through a diode to use it as a switch. The varactor diode alone won't draw any DC current, so R122 takes care of that.

73

I did remove 1 leg from D32, but I was wondering if also removing a side from R122 did more good or bad.

I was at least able to move around and transmit would follow along with receive, but I better verify with a 2nd radio to be sure it's receive was also tracking.

Thanks for replying Nomad. You Rule!

 

[nomadradio]

You need to put R122 back. If you look at the way the radio changes frequency when the clarifier is turned, you'll see some "lag" between turning the knob and seeing the frequency change. Gotta figure this would make clarifying the receiver more challenging.

73

 

[doffo]

You need to put R122 back. If you look at the way the radio changes frequency when the clarifier is turned, you'll see some "lag" between turning the knob and seeing the frequency change. Gotta figure this would make clarifying the receiver more challenging.

73

Will do. I will get to it tomorrow and report back.

 

[doffo]

You need to put R122 back. If you look at the way the radio changes frequency when the clarifier is turned, you'll see some "lag" between turning the knob and seeing the frequency change. Gotta figure this would make clarifying the receiver more challenging.

73

I restored R122. It now moved the clarifier up about a 1/8th of a turn to the right from where it was centered up yesterday. I was able to try it prior and it was at least following transmit/receive, but as you said, with a slight lag behind it.... Putting back R122 it seemed to of made it more responsive.

Much appreciated Nomad. I will edit the pictures in the original post to reflect to just move a leg of the diode off.