Frequency display and VFO stabilizer

[mark63]

Hi!

I make the project of Frequency display and VFO stabilizer Elektor 02/1998.

But when i power on i only can see 8 black (blank) characters on the lcd.

I Check the orientation of all polarized
components (electrolytic capacitors,
diodes, ICs, transistor T1) and all voltage and it's OK.
What can i do ?

I NEED HELP PLEASE
Mark
4Z7CBF

[Guest]

A few suggestions:

- PIC blank
- PIC contains wrong program
- Wrong config bits in PIC hence no oscillator activity
- LCD module has non-standard connections
- Wrong LCD contrast setting

Can u see activity on the PIC RBx and RAx lines. If not take a hard look at the PIC programming.

GonzoR

[mark63]

Dear GonzoR,

Hi !

I am re-program the pic16C54A and now i have new problem.

when i power on i can see the message "PHP1 EI9GQ ELEKTOR" and than the i see "57.0736 Mhz" .

why the counter start from 57.0736 Mhz ?

I build the project with pic16C54A and i program the pic without the fuse WDT.

ANY suggestions

Mark

[mark63]

ANY suggestions

Mark

[Guest]

hi Mark,

I did not actually build this project and just gave you a list of the most common problems people run into.
Apparently the PIC part of your circuit now works. I do hope someone else on this forum will be able to help you further with the analogue (VCO/PLL) part.

regards,
GonzoR

[sarma]

Hi,Mark Have you freshlyprogrammed another IC -- as PIC16c54is an OTP.

Sarma

[sarma]

Hi, Request Mark to put the VFO schematic used by him
the one i could get from the author' site ( thanks to him) is appended here

[sarma]

Hi, it is me again--
in the mean time i have made the PCB and assembled the VFO stabilizer. I had used PIC16F84 instead and thanks to Eamon Skelton- I have used Gadget40.asm

It is WORKING FINE.

thanks AGAIN to Skelton and to Editors of Elektor.

Ofcourse, one has to miticulously use HC series as changing them to LS did not yield expected result.

Hope this will enthuse Mark63- so he could complete his projject if not already done.

Regards
Sarma