PPS pulse problem still continue..

[lyova]

Hello,
My detector is been out of order since feb 2018… PPS pulse problem is still on, I have try to solve that by myself and with experts, but no solutions. Any new ideas here, or do I give up and throw my system to junk…

Hi Weather muurame  
Can I ask which GPS antenna are you using?
Have you tried to use GPS antenna with another working GPS device?
How many GPS satellites does your system see and how much signal in dB?
Does the GPS antenna see the sky, hope the antenna is outdoor?


P.S.
if you're still going to throw it in the junk can tell me  I can pick it up

Best regats, Volodymyr

I have tried it three diffrent gps module ( same model as it worked oroiginally), I am 99 % sure the problem is not in gps module.
As you see main fault is in pps signal, it rises too slowly. Next I have to chcek IC505 as dupreezed proposed.

   

I would also check the signal from 9 pins of the chip with no R703 resistor and the voltage at the points of the soldered resistor