VOIP Site Monitor / General Purpose IO Interface for Nano

The VOIP Site Monitor (VSM) is a simple expansion to VOIP nodes that adds essential remote monitoring and control capability. It easily connects to an RPI via USB. It uses an Arduino Nano’s integrated features and processes the raw data at a few Hz. A new C program, hosted on the RPi, communicates with an Arduino Nano (+ daughter board) and can be accessed via SSH or DTMF commands with Voice responses.

Although originally intended for a specific task, this is actually a convenient general purpose IO board for Arduino Nano's. With simple programming of the Arduino, you can have the system perform many home/hobby functions.


The Site Monitor provides:

· 4 channels of 10 bit A/D (Scaled 0..~20VDC)

· 4 discrete logic inputs that accept external open/gnd (door switches, etc)

· 4 discrete outputs which sink up to 0.5A each and can easily drive SSRs for higher loads.

· Temp Sensor! How hot/cold is it there?

· Easy USB interface to the RPi for VOIP applications or can be used to as for many home/hobby projects!

Access to the VSM is simple, via:

· SSH to your RPi to see the status of all the features, or

· Over the air DTMF and HEAR the RPI voice respond with values of voltages and the status of discrete IO and site internal temperature.

Use the analog inputs to monitor power supplies, solar chargers, batteries, etc. The ~20VDC Full Scale range accommodates PS overvoltage. Custom ranges are possible. Use the discrete inputs to monitor site door switches, lights, etc. Control equipment at the site using the discrete outputs. Each output can sink 0.5A (Open drain FET) and can drive a SSR for higher current loads (fans, heaters, etc.)

Each IO audio “label” can be customized to your specific site. You just create custom audio files using TTS already available on RPI’s. Enter file names in the “vsm.conf” file and hear the repeater/site status on your HT. Hear the voltage with descriptions of “solar charger, battery, or power supply” Discrete IO can be described as “door open, floor wet” etc. Make whatever you want using standard TTS tools.

Having problems with a site? Call the VSM program from crontab at intervals you desire!

Simple and convenient installation with screw terminal pluggable headers; one for each type of IO. No soldering at remote sites!!!

Small size (approx. 4 x 2.5”). Power from the RPi via USB or external DC, so no additional wallwarts or power supplies required.

The Site Monitor uses SMD technology and the daughter board comes mostly assembled with all SMD placed and soldered. Through hole parts can easily be user installed. The Arduino Nano is programmed using the standard IDE if future updates are desired.

In the photo above, the Discrete Outputs are wrapped back to the Inputs. Amber LEDs show the drive to the output chip (Toshiba TBD62003 open FETs). The Green LEDs show the input status. These are very helpful for trouble shooting. The little SOT-23 temp sensor is to the left of the amber LED.

All IO connectors are 5.08mm spacing pluggable headers which are easily removable for attaching wires with a small (but NOT jewelers size) screwdriver.

Current plans are to offer:

· SMD assembled daughter board ONLY. User installs through-hole connectors and supplies Nano.

PLANNED: Full featured kit of assembled daughter board, Arduino Nano (assembled), through-hole parts installed, USB cable (B to Mini). Nylon standoff and screws.

Support Forum

https://groups.io/g/VOIPSiteMon

It is strongly suggested that you join this forum for the latest info. SOURCE CODE FILES are available on the groups.io site.

Kit includes:

  1. PCB with all SMD parts soldered
  2. 3x Sets of pluggable headers for IO
  3. 2x 15pin female sockets for Nano

User needs to provide:

  1. Arduino Nano be aware that some ebay sellers use the word Nano in ads for other models. You need the model with the Mini USB connector and 15pins / row. Look at the photos carefully Est $3-5
  2. USB cable A to B Mini Est $1-2
  3. Standoffs and screws With many wires, the PCB can't be left to wander about.

Skills required to get it all going:

You will need to solder the provided connectors which is quite simple. In order to program the Nano, you will need to download and install the Arduino IDE. Programming is not difficult but it can take a couple of hours to figure this out if you haven't done it before. The Rpi program will have to be downloaded and installed. WinSCP works great for this; again some learning may be necessary.

Shipping is fixed at $3 for US customers. Usually I ship in <2 days and USPS takes 3-4 days.

Foreign customers can expect the post charges to be $15-20 depending on the country. Unfortunately, this can take 2-3 weeks. Write to me before placing an order. barry.w0iy @ gmail

Stock availability

The current plan is to assemble these units ahead of accepting orders. If these go fast, I may have parts availability issues which can take a week to resolve. Also, after the initial batch, there will be no production for 2-4 weeks while recommended improvements are reviewed and implemented.

The forum (listed above) will have the latest availability into.

Orders are now be accepted