Sinus 1watt PLL

[sinus trouble]

I would send the software and DIP switch settings but heres the link to the original site!

https://pira.cz/enpll.htm

[rigmo]

layout for play...

Rigmo, What is that?

Is it the Gerber Files in image format?

layout is working file for sprintlayout https://www.electronic-software-shop.co ... ut-60.html

[sinus trouble]

Ahh I see!

Thank you for uploading Rigmo! I have not used Sprint Software before!

[Gigahertz]

Nice one on the gerber files Sinus, Just taken delivery from JCLPCB

Keep me busy for a bit

[sinus trouble]

******IMPORTANT UPDATE******

Thank you to Gigahertz! A small but significant error in the schematic has been highlighted!

R2 and R3 were labelled incorrectly, No changes are needed in the PCB!!

I have attached the amended schematic!

Schematic_Sinus B2 PLL_2022-01-25.png

If anyone building this project is unsure about anything? No matter how small? Give me a shout!

[sinus trouble]

Nice one on the gerber files Sinus, Just taken delivery from JCLPCB

Keep me busy for a bit

Excellent Gigahertz!

I thought id see some funky colours, but you stuck to the 'Traditional Green'

Thanks again for the feedback!

[sinus trouble]

General setup proceedure is as follows!

Set all trimmers to mid position, Enter desired frequency setting on the DIP switch!

Apply 15V DC to the unit! The Lock LED should light for a few seconds then switch off!

If the LED stays lit? U15 (Purple trimmer) should be slowly adjusted until LED is off

PLL voltage can be verified via R8 using a multimeter (I find 5V to be a good threshold to allow correction headroom)

Once locked, Proceed to adjust U16, U17 and U18 for max power output!

Switch off and restart the unit, Lock state should resume if all is good!

The odd flicker of the lock LED is normal during operation! It means the PLL is operating correctly and reacting to any disturbance of the circuit!

[sinus trouble]

Just to add! The lock LED should give a short flicker at 30 minute intervals!

This is the PIC resetting parameters to refresh the lock status, Not a cause for alarm!

[sinus trouble]

I would like to say a massive thank you to Aron102 for the video! The build and setup is clearly explained throughout! He done an excellent job!

[Albert H]

Can I use KV1310/1330 inplace of the MV104?

Indeed you can! I have those in there currently and they work just as good!!

Another option Stephen Moss and I explored was to use zener diodes or LEDs as varicaps. The varicaps we'd used in various designs were shooting up in price, and they were becoming scarce - the big suppliers often didn't have any. I built a PLL Pro III test rig using reverse-biased 15V 1 Watt zener diodes to replace the varicaps. The tuning range was much the same, and the carrier was just as quiet. I then tried green LEDs for the varicaps - again reverse-biased. These worked reasonably well - until the potential difference across one or the other of them was enough for it to go into conduction! In the end, I compromised - I used the zeners for the PLL tuning, and the LEDs for the modulation! I found that the LEDs had to be painted black if light was falling onto them - in the workshop, under fluorescent lights, we got a low level hum on the modulation that disappeared when the LEDs were in shadow!

The (slight) downside is that the zener diodes give fractionally more noise on the blank carrier, but the price advantage was tremendous! If you're stuck for varicaps, give zener diodes and LEDs a go.

[radium98]

wonderful

[sinus trouble]

Can I use KV1310/1330 inplace of the MV104?

Indeed you can! I have those in there currently and they work just as good!!

Another option Stephen Moss and I explored was to use zener diodes or LEDs as varicaps. The varicaps we'd used in various designs were shooting up in price, and they were becoming scarce - the big suppliers often didn't have any. I built a PLL Pro III test rig using reverse-biased 15V 1 Watt zener diodes to replace the varicaps. The tuning range was much the same, and the carrier was just as quiet. I then tried green LEDs for the varicaps - again reverse-biased. These worked reasonably well - until the potential difference across one or the other of them was enough for it to go into conduction! In the end, I compromised - I used the zeners for the PLL tuning, and the LEDs for the modulation! I found that the LEDs had to be painted black if light was falling onto them - in the workshop, under fluorescent lights, we got a low level hum on the modulation that disappeared when the LEDs were in shadow!

The (slight) downside is that the zener diodes give fractionally more noise on the blank carrier, but the price advantage was tremendous! If you're stuck for varicaps, give zener diodes and LEDs a go.

There are also many current varicaps available, The only difference is that they are all SMT now!

These things are tiny but with some careful soldering? A pair of varicaps could be fitted to the existing pads!

It is unlikely i will re design the PCB unless there are some major changes? But it is something to consider?

[XXL]

Does this hum at all ? Every on frequency design iv tried hums. Half frequency never hums.

[yellowbeard]

Does this hum at all ? Every on frequency design iv tried hums. Half frequency never hums.

It's half frequency in the oscillator dude, the old Veronica/NRG design.

[rigmo]

doesn't the noise come from the SAA loop filter, i.e. the direct output from the PIC... that is solved with the 082 between...

[rigmo]

1T397 2.60 - 51.0 pF
MV209 - MMBV109 - MBV109 (BB103, BB109) 5 - 32pF 1 - 30V
BB209 2.6-31pF 28V
BBY40 6pF 32pF 26V 100pcs 8e
BB909B
BB809
BB709B BB619B BB619A BB504 BB502 BB439 BB409 BB204B
BB620 BB610 BB133
BB132 BB109G
BB107
MV2105 6-30pF
KV102A Russian КВ102А
KV1471E 6-40pF
BB910 axial, large range: 2.6-40 pF https://www.ebay.com/itm/222547098230 The winner

[sinus trouble]

1T397 2.60 - 51.0 pF
MV209 - MMBV109 - MBV109 (BB103, BB109) 5 - 32pF 1 - 30V
BB209 2.6-31pF 28V
BBY40 6pF 32pF 26V 100pcs 8e
BB909B
BB809
BB709B BB619B BB619A BB504 BB502 BB439 BB409 BB204B
BB620 BB610 BB133
BB132 BB109G
BB107
MV2105 6-30pF
KV102A Russian КВ102А
KV1471E 6-40pF
BB910 axial, large range: 2.6-40 pF https://www.ebay.com/itm/222547098230 The winner

Impressive Rigmo!

There are so many options available for varicaps!

[sinus trouble]

Does this hum at all ? Every on frequency design iv tried hums. Half frequency never hums.

ALL exciters are susceptible to noise in some way or another? Sometimes it is not the exciter that is causing the noise! (Maybe associated PSUs or PAs)

From tests i have performed on a decent quality linear lab PSU, very little noise is detected!

I cant guarantee that you will have the same outcome?

[Albert H]

The carrier noise on that type of circuit is very low. You have to make sure that your power supply is clean (a cheap Chinese wall wort won't give good results!). If you use a 3-terminal voltage regulator to feed the board, be certain to fit bypass capacitors (10n - 100n) to both the input and the output, both down to ground. I used to use the 7815 regulator, and actually solder 100n SM capacitors to its legs - this keeps RF out of the regulator, and considerably quietens things down.

Another trick I used frequently was a "gyrator" circuit (just a single transistor one) in the varicap bias supply, and sometimes in the supply to the Oscillator. This also reduces carrier noise.

I also used to supply the Vcc3 pin on the SAA1057 with 30V, to allow a wide tuning swing. I could (just) get rid of the trimmer capacitor in the oscillator, and have the circuit tune right across the band. Stephen Moss and I tried out that approach, and we were considering it for the next version of the NRG board. We derived the 30V from a simple oscillator and rectifier circuit (I've put it up here before), and it provided a worthwhile improvement. The next version of the PLL PRO was also going to have a more sophisticated phase comparator (but still made from discrete ICs). I have a nifty little circuit that I've used for years, which uses a 74HCT74 and a 74HCT00, and gives a really reliable locked / unlocked indication too. It has much lower phase noise than the 74HC86 EXOR gate that Stephen used for years.

[rigmo]

Impressive Rigmo!

There are so many options available for varicaps!

BB148
mv104


1T32 0.3/PCS
1T397 0.25/PCS
BBY40 0.3/PCS
KV1471ETR 0.3/PCS
KV1471KTR 0.3/PCS
KV1471TL 0.4/PCS