Hi Shirley, I happened to have a breakout board at home so I tried it immediately this morning. And it works fine! 2 things to look at: - Don't forget to remove the old, not working Si5351. (of course

#si5351a #40m

Hi Bernie, Long time ago I tried to repair an SMT board. That was not a success to say the least! I made a big mess of it. I promised myself never to try that again! So I go for the Si5351 breakout bo

#si5351a #40m

Sorry to hear that your Si5351A appears to have failed. Aside from the difficulties of soldering that SMD chip, there is the catch that distributors have no stock and aren't expected to get any until

#si5351a #40m

Rudd You can replace the chip yourself. There are several posts on this group and excellent videos on YouTube on how to remove and replace SMT parts. All you really need is a really good pair of small

#si5351a #40m

I just bought and assembled a qcx+ kit. I had the problem that the bpf filter did not peak. I did not get a nice square block signal from the Si5351. Then I got a "Si5351 error" message on the screen

#si5351a #40m

Here's my latest design notes (I should have included this with the pictures...) The ProgRock is designed to be a programmable crystal replacement. It uses an Si5351 synth board to generate pre-progra

#si5351a #progrock #vfo

Here are some pictures of the progress I've made so far. In the first two pics "parts top view" and "parts bottom view": The Synth board on the left (one with the crystal) plugs into the top of the Pr

#si5351a #progrock #vfo

A long time ago when updating the U3 to U3S it was necessary to remove pin 12 of the synth unit. I removed all mine and blocked the hole in the header. Then it will only go one way. Pin 12 remains red

#si5351a #progrock #vfo

That's a GREAT idea... If only I didn't already have all my Synth boards built... Every time I go to plug in a Synth board, I have to pause for a moment to think about orientation. Your way is so simp

#si5351a #progrock #vfo

When I built my last synth board, I used 1206 resistors in place of the vertically mounted components just to relieve the boredom of lockdown. Doesn't work for horizontally ones. No problems found and

#si5351a #progrock #vfo

My latest design path... I decided to keep the ProgRock in line as it has one feature I don't yet in my VFO code... GPS disciplined frequency control. For awhile I was struggling on the problem of whe

#si5351a #progrock #vfo

Sounds like a great idea to me.

#si5351a #progrock #vfo

Actually, looking over ProgRock's circuit diagram, I don't think I even need the ProgRock board. I can simply connect one Si5351a Synth board's output clock 0 to the crystal input at pin 2 on the seco

#si5351a #progrock #vfo

THANKS for pointing me in the right direction. I thought I saw something somewhere about "invert"ing the signal. I'm sure having a lot of fun with your kits. :) 73 km6wt

#si5351a #progrock #vfo

Yes, that would work, if... I was only interested in getting to lower frequencies. Changing the crystal on the Si5351a breakout board also works to get lower frequencies. Hans did this for the 180m QC

#si5351a #progrock #vfo

Yes, I saw that. But Hans is sometimes a super-perfectionist:-) I've used many Softrocks with 7474s and as I am sub-perfect they seem to me to work adequately. As for complexity, my suggestion is for

#si5351a #progrock #vfo

KM6WT I think you are right that if you use dividers for lower frequencies then the phase offset would be different for different division factors. Maybe a workable scheme might be to use division of

#si5351a #progrock #vfo

Thanks for your input Arv. I did try that, and it works fine for a single clock. But if I remember right, I could not get two clocks at 90° phase shifted. Maybe I did something wrong, or missed someth

#si5351a #progrock #vfo

Hello Mont For 180-degree phase shift you just set Clk0 and Clk1 to both be sourced from PLL A, and both with 0 phase offset. Then simply set the Invert bit in the control register for one of them. It

#si5351a #progrock #vfo

Perfect!! Thanks for your input Hans. AND for sharing all your research 3+ years ago. :) :) Yep, I was thinking the same thing. Probably easier then hooking up the serial port lines. In either case, I

#si5351a #progrock #vfo