BATC ADF435x PIC controller PCB

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G4IUG
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BATC ADF435x PIC controller PCB

Post by G4IUG » Wed Mar 05, 2025 7:32 pm

I have successfully built many of these and they are a godsend ! Thank you BATC.

However I have a couple for local BATC members and depending on how the power is applied (and probably its rise time)they will not always lock.

Sometimes the only way they will lock is to remove the power at the PCB and put the wire back in. Other times they just work.

I did notice that on a four frequency fat4sw with four different frequencies programed, that by changing frequency (using a rotary switch) they suddenly go into lock every time ?

Help ?

Dave
Ex G6ANG/T and G8EAO

VK5BI
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Re: BATC ADF435x PIC controller PCB

Post by VK5BI » Wed Mar 05, 2025 11:44 pm

An alternative to the PIC controller is the RP2040 zero. Cheaper and a breeze to program. Shown controlling the SV1AFN PLL.

Wayne VK5BI
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g4hiz
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Re: BATC ADF435x PIC controller PCB

Post by g4hiz » Thu Mar 06, 2025 7:48 am

Dave,

Try taking the PIC 3.3V supply from the synth board, its usually available on the 10-way connector. What's possibly happening is that the synth supply hasn't established itself properly before the PIC tries to talk to it.

Jen

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G4IUG
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Re: BATC ADF435x PIC controller PCB

Post by G4IUG » Thu Mar 06, 2025 8:22 am

Hi Jen

Thanks, whilst I was writing this, that did occur to me. My systems here (various) use the BATC board for the power input so I may try running the DDS off the PIC regulator ?

Secretly I was hoping someone versed in C could put a line in fat4sw.c to always give say 100ms pause for the ADF to settle ? (Russ ?)

BTW Jen, you could not imagine how influential your demonstration was at the Ridgeway Roundtable !

73 Dave
Ex G6ANG/T and G8EAO

g4hiz
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Re: BATC ADF435x PIC controller PCB

Post by g4hiz » Thu Mar 06, 2025 11:40 am

Hi Dave,

Indeed with all my PIC programs controlling synthesizers of various sorts, I always have as the first action a 0.5s delay to allow for PSU stabilisation across the various entities involved.

Thanks for the comment on Ridgeway. If folks are interested, I can do a similar demo at CAT25.
I would always be available to address any questions, bearing in mind that I am an RF & Space Systems specialist rather than s/w engineer. Any questions, please ping me a PM on the forum.

73 to all
Jen G4HIZ

g4saq
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Re: BATC ADF435x PIC controller PCB

Post by g4saq » Thu Mar 06, 2025 3:46 pm

@G4IUG Dave, I have modified the code to include a 500ms start up delay in order to give the synth chip time to initialise. I have sent this to your email. Please test on your hardware and reply here as it might be of use to others.
BW, Russ, G4SAQ

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G4IUG
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Re: BATC ADF435x PIC controller PCB

Post by G4IUG » Sun Mar 09, 2025 10:11 am

Hi Russ

Many thanks ! I haven't been able to test all variants (more in a PM) but yes it does work on the critical unit perfectly !

73 Dave
Ex G6ANG/T and G8EAO

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