Freq entering the 4059 is going to be 10.9375 MHz for 87.5.

Thank you nrgkits.nz

Can you explain.me how they use this hef4059
And not hc or hct a cmos and not a ttl.

Designs like that usually have a prescaler chip that devides the input from the oscillator by 64 or 100, depending on the design. In that photo its either the SIL chip or the 8 pin chip. This means the frequencies futher along the circuit are in the 1-2MHz range and you can use the regular CMOS chips.

thank you yellowbeard now it is all clarified to me ,thank you everyone .Yess in fact it is the sil socket 6pins of a prescaler U664B teiler divider by 64 .

The problem with pre-scaling is that the reference frequency also has to be lowered , to keep the step size at 100kHz. A lower PLL reference requires a better loop filter to keep whistles out of the modulation, and increases lock-up time.

It's easiest to use an all-in-one PLL like the TSA5511, which can handle the frequencies that we're interested in without the need for a prescaler. This particular IC is programmed using the I²C bus, and the easiest way to generate the necessary codes is with a PIC or an AVR IC. I prefer the PICs. My PLL uses a 16F628 and the 5511 , and drives an LCD display, giving supply voltage monitoring, modulation depth monitoring, temperature monitoring, and even a silence detect output in case a link input is lost. The whole component cost for the PLL section of my exciter is about £10, including the crystal (6.4MHz) and the display (40 characters by 4 lines).

The other approach is to use a fairly fast pre-settable divider in a "conventional" PLL. One approach was to use the 74HCT4059, with a 74HCT74 giving a ÷4 of the output frequency (actually dividing the ½f oscillator by 2). This allowed the use of a 25kHz reference (derived from a 4MHz crystal), which is ultrasonic enough so that the loop filter can use (relatively) fast time constants and small value capacitors, and not end up in the modulation. It also allowed me to use my favourite phase comparator (using the other half of the 74HCT74 and a NAND gate (74HCT00) feeding into the two inputs of a low noise op-amp. The three redundant NAND gates in the package were used for the lock / unlock detection and indication, providing a solid signal to switch the PA. Some versions of this PLL got rid of the expensive 74HCT4059, and used the 74HCT4040 with diode programming to cut costs.

PLL design (and particularly loop filter design) isn't trivial, but it's easier than ever these days to use the on-line calculators to design them.

Here's mine using Alberts 5w design, the pic code I wrote myself using mplab ide and hitech C, bit banged the i2c as the 16F628 doesn't have any i2c registers.

good one .

do any of you got a design of a separate digital wattmeter with 16f88 and can detect swr alaram and monitor audio deviation and temperature as a diy project .or low cost one

nrgkits.nz wrote: ↑Tue Jul 31, 2018 12:10 pm Here's mine using Alberts 5w design, the pic code I wrote myself using mplab ide and hitech C, bit banged the i2c as the 16F628 doesn't have any i2c registers.

That's a prettier board layout than I came up with! There are libraries with I²C emulation for the 16F628 - that's the way I went. The 5 Watt board has proved to be a winner for driving big output bottles directly. LB has a couple of big valved strip-line tuned PAs with homebrew tuning and loading capacitors at the high voltage end, and the exciter is in a small diecast box in the bottom of the PA cabinet! The one I saw last week delivered 2½kW for 70 Watts of drive, so he added an interposing FET driver. It was (originally) a nasty Italian sprogbox (and they were very big sprogs!). He found that the PA is absolutely clean if it's fed with a clean source....

Our version of the 5 Watt exciter has more screening than yours - we separate the output filter from the rest of the board, and the regulation and logic is also separated (and on a separate groundplane) to keep the conducted noise to a minimum. The PIC is a noisy little bugger, so it's good to keep it well clear of the modulator!

A further modification we've done is to add a brickwall zener diode clipper to the multiplex input to completely prevent any chance of over-deviation. If you put too much level in, you just get really nasty sounding mod! The VCO now has the same sensitivity right across the band (using a couple of extra varicaps to change the modulation sensitivity). I'll email you the details of the updates, though it looks like your board is the finished article!

Here's the phase noise measurements, provided by a guy who bought one of my assembled 5w boards.

I would like to buye a nice transmitter like this where everything is inside but my problem thoses itwms prohibited douane in my country so sad .so why i go DIy project .Excuseme .

nrgkits.nz wrote: ↑Wed Aug 01, 2018 11:28 am Here's the phase noise measurements, provided by a guy who bought one of my assembled 5w boards.

Nice! That's quiet!

i have just bought today the 74HC4059E and fitted in its place i still have no lock what is next step VCO is okey .dip switches ok all IC tried in a veronica pcb and work .i have always here the green LED lighting stable.

You really need a scope to find out what's going on

nrgkits.nz please see the parts around the lock led are they correct ?

i work with frequency meter .