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Andrew_G
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Joined: 18/10/2016
Location: Australia
Posts: 871

Posted: 03:09am 07 Jul 2019

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Peter(B), many thanks for your kind offer. I have similar boards here and spare HC-12s - I'm thinking of making up a unit that only measures the voltage and sends it via HC-12 - leaving the weather station churning away (but see below).

Mick - good to see that you got out of Melbourne. Been good weather for a while now though. As to your questions:
- the MCP1700 powers the MM170, the voltage divider to pin 24, and (via a 10k resistor) the wind direction sensor which is a set of resistors from 688 to 120k ohm. That should be OK; shouldn't it?
I can reconfigure it all and power the wind direction sensor from 5V.

- 2x 1uF caps (I think Geoff uses 10uF in the backpacks??) - BINGO I've not put them in! That was a good question Mick - probably the answer too! (This was the first circuit I made with the MM).

Rather than fiddling with changes to my veroboard I'll use one of your MuPs to do it properly.

Many thanks to all,

Andrew

bigmik

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Joined: 20/06/2011
Location: Australia
Posts: 2950

Posted: 12:48am 11 Jul 2019

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How did you go Andrew?

Regards,

Mik

Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<<

PeterB
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Joined: 05/02/2015
Location: Australia
Posts: 655

Posted: 03:43am 11 Jul 2019

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G'Day All

I am beginning to think that Andrew is running 5V down a very long cable. If so,that would worry me. It would be better to run e.g. 12V and then regulate up the stick.
It just happens that the board I offered to give him does just that

Peter

Andrew_G
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Joined: 18/10/2016
Location: Australia
Posts: 871

Posted: 05:31am 11 Jul 2019

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Mick and Peter,
Many thanks for checking up on me.
Whilst I am designing a new layout I "fiddled" with the code a little (inserted a "Watchdog = 60000" in one loop in case the GPS is delayed in getting a fix).
And stuck it up the pole again (without the capacitors).
I have also finished a program on the PC that logs (adding Date$ and Time) all communications on my HC-12 network (in case there are collisions impacting anything). (I do use NMEA-like checksums but without this I have no idea of any collisions).
So far it has been going for four days with NO problems. I am only seeing between 4.95 to 5.06 volts and pretty much always 5.0V. I can now replay events to help track problems.
This is still making me suspicious that it may be/have-been code?
(Edit: Since posting this I've had a quick look at one log and I can see some transmissions that could mislead my code into false voltages - I need to improve my code to be a bit more critical of what messages to accept vs discard - AG)

The 5v power cable is about 5m, from a Jaycar 5V power supply from a mains GPO in my shed.
I am ultimately keen to run it off a solar charged 12V battery (I have several decent deep cycle AGMs off my boat).

Peter do you think your gear will help, and is your offer is till open?
(If so let me know and I'll PM you my details).

Regards,

Andrew
Edited by Andrew_G 2019-07-12

PeterB
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Joined: 05/02/2015
Location: Australia
Posts: 655

Posted: 06:11am 11 Jul 2019

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Andrew

The board is 75x63 and contains 28 pin chip, 7805, LD1117V33, 3x electros, 47uF, ICSP,
4 pin I2C, CONSLE TX RX, COM2 TX RX,pins 26 & 24plus a few others.
It is my first go at PCBGOGO and the only problem is a couple of headers are too close.
It is just the thing for trying out ideas.
I have some of the bits if you need them e.g. 47 uF, 170.
And it has 4 bolt holes and I have probably forgotten something important.

Peter

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