President Grant PC-999AD

[Ghibli69]

Hi
I have this presdident grant ( pc-999AD ) with the black mask with the coarse and the fine.
I look for the modification to unlock rx/tx the clarifier (fine and coarse)

Thank's

 

[sp5it]

This clarifier is factory unlocked.
Mike

 

[Ghibli69]

Hi Mike, thanks for the reply,
but it is not so, with the coarse I can change the frequency in TX and RX, but with the efine it moves only the frequency in reception.

 

[Redbeard U812]

Have you tried CB Tricks......

http://cbtricks.com/pub/secret_cb/radio/uniden_president.htm

 

[Ghibli69]

Thank you for the reply, but these are the mod for the PC-999AB grant, I have tried this:
1) Cut D-45.
2) Find D-79 and jump it (Solder a wire across it)
3) Remove r-120 and replace it with a 470 ohm resistor.
4) Find the BLUE wire from the clarifier knob and cut it just before it connects to the PCB. Solder it into the hole that is next to where R-120 is.
5) Find the GREY wire from the clarifier knob and cut it just before it connects to the PCB. Solder it to a constant 8.5
The coarse moves to rx and tx, but the fine seems disabled.

 

[Ghibli69]

the radio is like this, in the back there is also the socket for the external s-meter

 

[sp5it]

Hi Mike, thanks for the reply,
but it is not so, with the coarse I can change the frequency in TX and RX, but with the efine it moves only the frequency in reception.

Works as it should. Why you need fine track tx?

 

[sonoma]

here is what I found for the pc999 board on the Defpom site. hope this works for you

1) Cut D-45.
2) Find D-79 and jump it (Solder a wire across it)
3) Remove r-120 and replace it with a 470 ohm resistor.
4) Find the BLUE wire from the clarifier knob and cut it just before it connects to the PCB. Solder it into the hole that is next to where R-120 is.
5) Find the GREY wire from the clarifier knob and cut it just before it connects to the PCB. Solder it to a constant 8.5 volt supply.(This can be the center pin of TR-39 )

looks like it is what you posted already

 

[Ghibli69]

Hi Sonoma,
This is the modification I made, using a voltage stabilizer for the 8v.
But the fine does not work.

 

[Ghibli69]

Works as it should. Why you need fine track tx?

Because in SSB with more than two interlocutors it becomes difficult to do isofrequency.

 

[sp5it]

Not at all. You do it that with coarse knob. No mods involved.

 

[Ghibli69]

I prefer the mods that allows me to move in rx and tx at the same time.

 

[sp5it]

That is what COARSE knob do. No mods, pure factory
Ever tried to rotate it?

 

[Ghibli69]

I know how coarse works, but that's not the point.
I want to mods the Coarse and Fine so that they work in rx and in tx.

 

[sp5it]

Ok, than after mod how do you tune to other station which is a little out of freq without moving your transmitter?
Mike