more ecg docs

userguide/ecg.md

@@ -3,12 +3,20 @@ title: "ECG usage"
 weight: 60
 ---
 
+[![ECG usage with a finger](/media/ug/5-ecg-finger.png)](/media/ug/5-ecg-finger.png)
+
 The card10 features a single channel ECG sensor. There are two
 general ways how to use it (there are more, see the "Contact options" section):
  - Wearing the card10 on your wrist and pressing a finger on one of the gold contacts
- - Attaching a USB-C to ECG electrodes adapter
+ - Attaching a USB-C to [ECG electrodes adapter](/tutorials/ecg_kit_assembly/)
+
+Using external electrodes will provide better signal quality and offers more flexibility on what and
+how to measure.
 
-Using external electrodes will provide better signal quality and offers more flexibility on what and how to measure.
+{{% notice warning %}}
+Do not attach a USB connection to the card10 while waring it. It is a safety hazard
+(think electric shock because of a bad USB power supply) and it also makes the ECG measurements unusable.
+{{% /notice %}}
 
 Currently there are two ways how to see and save the data:
  - Using the ECG app on your card10
@@ -20,6 +28,7 @@ If you have your card10 paired to an Android phone you are also able to send the
  - card10 firmware v1.18 (Queer Quinoa)
  - card10 companion app v0.9 (Attention: Not yet available on F-Droid main repository)
 
+[![ECG app](/media/ug/5-ecg-app.jpg)](/media/ug/5-ecg-app.jpg)
 
 ## ECG app menu options
 
@@ -30,6 +39,7 @@ navigate between the different menu items.
 ### Mode
 Use this to switch to switch between using your wrist/finger as a contact or external electrodes, connected
 via USB-C.
+[![Mode option in menu](/media/ug/5-ecg-menu-mode.jpg)](/media/ug/5-ecg-menu-mode.jpg)
 
 ### Bias
 The bias option selects if a small bias voltage should be applied to the positive and negative ECG electrodes.
@@ -41,6 +51,7 @@ supplies the bias voltage. In this case you can experiment and turn off the bias
 
 It is highly recommended to have this option active when using external electrodes, as you don't
 need to have the back of the card10 connected to your body in that case.
+[![Bias option in menu](/media/ug/5-ecg-menu-bias.jpg)](/media/ug/5-ecg-menu-bias.jpg)
 
 ### Rate
 The sample rate at which the data is taken by the sensor. The default is 128 samples per second. So far this seems to be plenty. You can increase it to 256 samples per second if you want to.
@@ -52,10 +63,41 @@ external electrodes. If you use external electrodes, give it a try and turn of t
 
 The signal written to the log file or transmitted via BLE to the Android app is not affected by this filter.
 It is purely for displaying the ECG data on the card10's screen.
+[![Filter option in menu](/media/ug/5-ecg-menu-filter.jpg)](/media/ug/5-ecg-menu-filter.jpg)
 
 ## Contact options
 ### Finger
+[![ECG usage with a finger](/media/ug/5-ecg-finger.png)](/media/ug/5-ecg-finger.png)
+
+## Finger ECG
+
+![Top View Harmony Board](/media/ug/5-ecg-top_1-4.jpg "Finger ECG and Pulse Oxymeter")
+
+Your card10 comes with a number of fun things to play with
+
+  - 1   : Contact,  negative ECG electrode
+  - 2   : Pluse oxymeter (can [potentially, if at some point supported by software] measure pulse and blood oxygen
+levels using an optical sensor)
+  - 3   : Contact,  negative ECG electrode (again)
+  - 4   : Screw (also works as a negative electrode, see [8])
+
+
+![Bottom View - ](/media/ug/5-ecg-bottom_5-6.jpg "COM for Bias and positive electrode for finger ECG")
+
+  - 5 : COM (for bias)
+  - 6 : Contact, positive ECG electrode
+
+![Side View Details](/media/ug/5-ecg-side_front_7-8.jpg "Pin and isolation")
+
+  - 7 : Pin for soldering/stitching an alternative electrode, if you don't want to use (6)
+  - 8 : Plastic distancer, works as an isolation (see [4])
+
 ### USB-C
+[![ECG usage with a USB cable](/media/ug/5-ecg-usb.jpg)](/media/ug/5-ecg-usb.jpg)
+
+  - see [ECG Kit Assembly](/tutorials/ecg_kit_assembly/) on how to solder your ECG cable
+  -  NB: it DOES matter how you connect the kit via USB. if you get a lot of noise, try to turn the connection
+
 ### Wristband contacts
 
 ## Logging