Cobra 200 Rev 2 Clarifier Range

[Animal]

Guys

A friend of mine has a Revision 2 Cobra 200 GTL DX (PCB# PFM-0090A-BE)

It's well documented that the coarse clarifier shift isn't sufficient on the Rev 2 to reach the zero's (obviously it needs 5Khz at the very least but only manages approx 3Khz)

I'm led to believe there are a number of ways to increase the frequency shift of the clarifier.

Does anyone know the easiest way to correct this problem on the Cobra 200???

Many thanks

[Rick]

Change crystal X2.
Common fault.

[Animal]

Thank you Rick - excuse my ignorance, I take it X2 is 10.240Mhz reference?

[Rick]

X2 is the PLL loop Osc.
X2 is a special crystal and not just any old 10.2400 MHz will do.
You will need to realign the PLL loop Osc when you replace the crystal.
Have a word with Richard at Truck King he may still have some, you can tell him that Rick from Euro Radio Co put you in touch.

[Animal]

Cheers Rick, I've done just that - Richard said 'Rick who?'

Hope you can give me some guidance when I come to re-align the PLL loop osc

Thanks again, much obliged.

[Rick]

It would be best to do a full realignment job.
You will need a good frequency counter at least 6 digit with a 10:1 probe.
The info can be found on CBTricks.
http://www.cbtricks.com/radios/cobra/20 ... e_info.pdf

If you are stuck with it, I can do it for you but it is not free.

[Animal]

Would it be cheaper than buying an Anritsu or Marconi test set???

Can you send me a PM with your 'phone number please Rick?

Many thanks.