PLL CMOS FM since 1979

[rigmo]

PL CMOS FM is wanted from the late seventies.
Does anyone have documentation.

"
How to find part list for this project - schematic? Penelope gilda pll by ghz.it
PLL FM CMOS the first one original by Mario Bragheri IK1SPF= mareleletronica.it assembly from 1979, GHz.it is second copied in 2000. Third copied again by IW1CGW in 2005.
"The first pll cmos I did in 1993, unfortunately I'm losing all documentation for this cmos. I've been searching the internet since 2018, where I recognize the circuit on the ghz.it stations. I thank God for giving me this honor and giving me the joy of finding out who did it. I wanted to do it again after 30 years."
"

[Albert H]

That's quite similar to one of my early ones. The VCO was divided by 100 using an SP8629, then through a 4024 to further divide by 8. The presettable divider used 4028s (as I remember) to convert the four BCD inputs to binary for the divider ICs. The frequency was set with a row of four BCD rotary switches.

It was a grossly over-complicated circuit, but had to be done that way - at the time - for easy programming. A couple of years after this was designed (around 1976 I believe) in 1978, 74HC logic became available, and I could do the same as the circuit above with just four cheap ICs. My PLL used diodes for programming (so was slightly more complicated to set the frequency), but cost almost nothing to build....

Another PLL that was often used by pirates at the time used an SP8629 divider then ordinary cheap CMOS at around 1 MHz for the PLL logic.

Most pirate PLLs used the 4046 for their phase comparator, but I preferred to use my own (slightly more complicated) phase comparator with a 74HC74 and a 74HC00, which gave a good, clean output to the loop filter and provided accurate locked / unlocked outputs to switch the PA.

[rigmo]

Albert H do you heave SP8660?

[reverend]

http://web.archive.org/web/200408090802 ... xgilda.pdf

[reverend]

Having looked at the circuit, I really like the idea behind the delay on the lock detector. Only thing is that although it waits a couple of seconds after locking before enabling the output, it latches the output on. So if the loop loses lock, it will keep transmitting!

[rigmo]

still no part list value

[Albert H]

Having looked at the circuit, I really like the idea behind the delay on the lock detector. Only thing is that although it waits a couple of seconds after locking before enabling the output, it latches the output on. So if the loop loses lock, it will keep transmitting!

That's why I preferred a proper lock detector!

[rigmo]

That's why I preferred a proper lock detector!

Can you explain.

[Albert H]

Phasecomp.png

This is the phase comparator and lock detector I used for years. I also used the lock detect output to switch 4066 gates to increase the value of the loop filter timing capacitors when lock is achieved - this would give very fast lock up (around 2 seconds) but would then switch into a "slow" mode with a time constant of around 12 seconds, to prevent the PLL affecting the lower frequency end of the frequency response at all! The PLL would remain in lock, but the audio was superb - it overcame the usual compromise between lock-up time and frequency response. If the PLL went out of lock (the usual test with the finger dabbed on to the VCO coil, the loop filter would return to "fast" mode, and correct the frequency rapidly, then slow down again to benefit the audio.

[fmmpastouni]

Phasecomp.png

This is the phase comparator and lock detector I used for years. I also used the lock detect output to switch 4066 gates to increase the value of the loop filter timing capacitors when lock is achieved - this would give very fast lock up (around 2 seconds) but would then switch into a "slow" mode with a time constant of around 12 seconds, to prevent the PLL affecting the lower frequency end of the frequency response at all! The PLL would remain in lock, but the audio was superb - it overcame the usual compromise between lock-up time and frequency response. If the PLL went out of lock (the usual test with the finger dabbed on to the VCO coil, the loop filter would return to "fast" mode, and correct the frequency rapidly, then slow down again to benefit the audio.

Hello Mr Albert.Can you post a schematic with the implementation and the part values of this dual speed pll?It would be great.

[Albert H]

Take a look at the Broadcast Warehouse PLL Plus that used a similar loop filter switching scheme, though they used the MC145170 PLL (which I always found to be a horrible IC!).

My PLL just used a SAB 6456 prescaler, then a 74HC4059 programmable divider (with BCD-coded rotary switches, so that you could simply dial up the frequency you wanted), a 74HC4060 for the crystal reference oscillator and the phase comparator above, with a 4066 used to switch extra capacitors into the loop filter to slow it down when locked. There was also a simple delay circuit using an NE555 to drive a small relay to switch on the PA a few seconds after the PLL had locked.

My company did a nice surface-mounted version of this PLL for some years, and it was used by several manufacturers in their FM products (Marti used it in their portable links!). The documentation is out there if you want to go to the trouble of building it!