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Re: MonRDS Noise issues!!

Posted: Thu Jul 01, 2021 8:14 am
by radium98
thank you , yes will took an idea . i saw an old schematic that use 4046 and another ic , and anther that use the little pic and derive thoses signal , but if you can help more but i need it to be applicable on the circuit i use above .it seems to me like the same principle of the pll , only diff is this for the phase and there will be no voltage correction here ? correct me please if i am wrong.

Re: MonRDS Noise issues!!

Posted: Thu Jul 01, 2021 3:27 pm
by Krakatoa
If I understand correctly your question: inside the 4046 there is a PLL circuit as well as a VCO. You can use them together or separated, see the datasheet.
For example, in one design I did I used a 456khz oscillator and with the 4046 and an external fliflop I multiplied it by 2 up to 912khz and from there you can use integer division ratios for all the clock signals in an oversampling stereo coder (304, 152, 76, 38 and 19khz) and the RDS (57 and 1,1875khz)

Re: MonRDS Noise issues!!

Posted: Thu Jul 01, 2021 11:20 pm
by Albert H
My PCB version uses a 18.240MHz programmable "MEMS" crystal oscillator module divided by 10 (with a 4017) then uses a couple of diode programmed 4020s to derive the required signals.

I've also used 4864 kHz rocks multiplied and divided to give the required frequencies. One version used a PIC to provide the various frequencies derived from a 16 MHz crystal, but I had jitter problems....

Re: MonRDS Noise issues!!

Posted: Thu Mar 16, 2023 10:42 am
by rigmo
Latest monRDS software aviable? tnx

Re: MonRDS Noise issues!!

Posted: Thu Mar 16, 2023 6:18 pm
by 3metrejim
Working on it, serial port routines tested, waiting for radium98 to get back to say whether the RDS data is still ok or if changes have corrupted it. I don't want too many possibly non-working versions floating about. I don't have the right parts to fully test.