The Defpom Forum, for RadioMods, S&M Software and Music by The Defpom

I am building a b kit and need the crystall information for that model. I dont have one here in the shop to compare it to. Any information would be appreciated. I already looked at cbtricks too.

Mike

What model radios use the B-Kit? I don't normally stock the B-Kit but I can possibly calculate the crystal frequencies for you. What PLL chip is in the radio and if possible, what is the current mixer crystal in the radio?

its a 142gtl radio. the mixer crystal is 10.24mhz and the pll is a mb8719.

thanks

MIKE

speedracer6g wrote:its a 142gtl radio. the mixer crystal is 10.24mhz and the pll is a mb8719.

thanks

MIKE

That is the reference oscillator crystal, you don't want to change it, you will find another crystal, either an 11.3258 or an 11.1125, Depending on if pin 10 of the PLL is tied high or low.

Sorry got the wrong one it is an 11.1125 crystal. I know that the 11.325 crystal is .150 up and down from 11.325. Is it the same for 11.1125.

MIKE

Yes, I have the data somewhere at work and I will have to peek at it.

Divide the difference in frequency by 3, to give you the required frequency, as the 11MHz crystal is tripled before mixing in the the VCO.

So if you want 1 band up (or down), divide 450KHz by 3 to give you 150KHz, which is the difference in frequency from the original crystal and go from there.

I have the kits that will work with the 11.3258 crystals so i think i will just lift the 10 pin of the pll and put in the 11.3258 crystal and use that kit. I checked my suplier for the crystals i need to do that mod and they dont have them so i will just change the crystal and mod the pll.

thanks guys,

MIKE