bigal_scorpio
Active Member
Hi Al,
I have built the LCF meter, on the bench, used the last 16F628A program in a PIC.
As I explained earlier the frequency of the CAP osc can be very high at switch ON.
This high freq is connected from the 4011 pin10 to the PIC pin 12 via a 10k resistor.
The high freq at the PIC pin after its passed thru the 10K is insufficient to switch the Tmr1 input,
so the program waits forever.!
Reduce the 10K0 [R5] to 4K7 [ put another 10K in parallel if its easier]
This fixes the problem 100% on my test set up ...
Can you give it a try, leave the test prods open as per the designers instructions.
Let me know what you find..
I know that the 10K is there to protect the 4011 output when an external freq is input,
but the 4K7 should get the same result.
Hi Eric,
You've done it again, may have to start calling you sherlock!
The resistor fix makes my meter work without locking with either Pic in!
Maybe now Bob can build his meter.
All the best............Al