Re: No PTT


Geoff Theasby <geofftheasby@...>
 

Hi Jerry,

It is entirely possible that 12 volts has been inappropriately applied. I did find the odd wiring error.

It was working, briefly, immediately after 'tune up'. So I have no doubt it was shipped in working order. 

I shall apply your idea for pull-up resistors (Tomorrow - I am rather tired now)


Thank you again,
Geoff

On 26 April 2018 at 15:38, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:
You are correct, the encoder switches are wired to the two pins on the upper right
of the Raduino.

This is really weird.
The "LSB A 7.150" suggests the Raduino is mostly working correctly.
We've seen Nano input cells get blown like this, but usually happens when somebody
wires something up wrong and maybe puts 12 volts on a Nano pin somehow.
I believe the Raduino gets checked out before leaving hfsignals.

You might try adding 4.7k pullup resistors (anything between 1k and 10k will do)
from each encoder signal to the Raduino's 5v rail.
So add a resistor at the 8 pin connector on the front of the board from the pin on the
upper right at the 8'th pin location (has a black wire, one of the encoder signals)
to the 6'th pin in from the right (has a green wire, tied to 5 volts.
Add another resistor from the second in in from the upper right (brown wire, 
second encoder signal) to the 6'th pin in (green wire, 5 volts).
This might fix the problem with the encoder if all that is failing is the Nano's
internal 30k pullup resistors, but the Nano's input buffers are still ok.

You can extract unused wires from the cable harnesses by pressing
the retaining clip of the pin through the hole in the white connector shell
while tugging gently on the wire.  That avoids any possibility of wires flying
around and touching things they should not.  Alternately, put tape over the
ends of all unused wires.

Anything you do to make this thing work is not cheating in my book.
Good luck!

Jerry


On Thu, Apr 26, 2018 at 06:36 am, Geoff Theasby wrote:
Set up as before, reads "LSB A 7.150". No voltage detected at the pins in question. Checking with the ohmmeter (Raduino switched off) at the encoder shows continuity on-off-on-off as the knob is turned. Both pins similar, but out of phase of course. 
So, no volts from Raduino. (Display facing up, using the two pins at extreme right)


Join BITX20@groups.io to automatically receive all group messages.