finish post (refs #15)

container/site/content/posts/bicycle-headlamp/index.md

@@ -14,7 +14,7 @@ Nighttime bicycle rides in the summer are ideal:
 - 🚘 little traffic
 - 🦝 nocturnal wildlife 
 
-But it is not easy to see in the dark, so I bring a headlamp and okay, fine, this works. With my current head lamp I can see and be seen just fine. But there are some limitations. I see wonderfully directly ahead of me in the narrow cone of light provided, but at the edges of this light cone I see practically nothing at all, as though I am looking through a paper towel roll. The beam pattern is optimized for riding in a straight line, with little regard for what lies in the periphery. **I would like a greater field of view, so I will need a lamp with a wide beam pattern.**
+But it is not easy to see in the dark, so I bring a headlamp and okay, fine, this works. With my current head lamp I can see and be seen just fine. But there are some limitations. I see wonderfully directly ahead of me in the narrow cone of light provided, but at the edges of this light cone I see practically nothing at all, as though I am looking through a paper towel roll. The beam pattern is optimized for riding in a straight line, with little regard for what lies in the periphery. I would like a greater field of view, so I will need a lamp with a wide beam pattern.
 
 ## 🔦 Headlamp
 I start by selecting the headlamp. This is the most important component, and everything will revolve around it. My selection criteria is simple. The light must have these features:
@@ -41,7 +41,19 @@ I had to settle for the **OPL5 Motorcycle LED Headlamp**:
 
 {{< image src="images/opl5-motorcycle-led-headlamp.png" >}}
 
----
+
+## 🔋 Battery Sizing
+Since the headlamp consumes 48 W, I need a battery that can sustain this load for a couple of hours without totally draining the battery. I can see how long a given battery will endure.
+
+- $t$ = run time (hr)
+- $E_\text{battery}$ = battery energy (Wh)
+- $p_\text{load}$ = LED headlamp power (W)
+
+$$
+t = \frac{12.8 \text{ V} \cdot 16 \text{ Ah}}{48 \text{ W}} = 4.27 \text{ hr}
+$$
+
+✅ **This will work**. It is a comfortable, if not excessive, amount of energy for the headlamp.
 
 ## 🧰 Case
 I selected a cheap weatherproof case from *Harbor Freight Tools*. It will be large enough to accommodate many sizes of batteries, since battery packs of the nature I seek are almost always composed of a bunch of even smaller batteries, typically the 18650 type batteries. The dimensions of this battery type are also its namesake: **18 mm dia. × 65 mm l**. 
@@ -55,40 +67,24 @@ I mention all of this because the height dimension of the battery packs are almo
 
 {{< image src="images/apache-1800-case.png" >}}
 
----
 
 ## 🔋 Battery
-Since the headlamp consumes 48 W, I need a battery that can sustain this load for a couple of hours without totally draining the battery. I can see how long a given battery will endure.
-
-- $t$ = run time (hr)
-- $E_\text{battery}$ = battery energy (Wh)
-- $p_\text{load}$ = LED headlamp power (W)
-
-$$
-t = \frac{12.8 \text{ V} \cdot 16 \text{ Ah}}{48 \text{ W}} = 4.27 \text{ hr}
-$$
-
 I selected a cheap, unremarkable 12 V battery with a capacity of 16Ah.
 
+✅ This will be fine. 
+
 {{< image src="images/nermak-12v-16Ah-LiFePO4.png" >}}
 
-
-✅ **This will work**. It is a comfortable, if not excessive, amount of energy for the headlamp.
-
----
-
 ## 🔌 Switches and Ports
 I splurged on a nice weatherproof SPST switch and mounting bracket.
 
 {{< image src="images/bss-contura-iii-spst.png" >}}
 {{< image src="images/bss-contura-iii-mounting-bracket.png" >}}
 
-The port that will feed power to the headlamp power is some kind of 'SAE' connector, which as far as I can tell do not actually comply with any official standard. They are used for a lot of things in weird cheap Chinese electronics, and I could have selected a better connector. I selected this mostly because it matches the connector on my battery charger and it is cheap and ubiquitous. It will be adequate.
+The port that will feed power to the headlamp power is some kind of 'SAE' connector, which as far as I can tell do not actually comply with any official standard. They are used for a lot of things in weird cheap Chinese electronics, and I could have selected a better connector. I selected this mostly because it matches the connector on my battery charger and it is cheap and ubiquitous.
 
 {{< image src="images/SAE-connector-socket.jpg" >}}
 
----
-
 ## 🔩 Parts List
 | Part |
 |-|
@@ -98,22 +94,9 @@ The port that will feed power to the headlamp power is some kind of 'SAE' connec
 | SAE Power Socket Port |
 | Inline Blade Fuse Holder + 5 A Fuse |
 | Blue Sea Systems Contura III OFF-ON SPST Switch + Mounting Panel |
-| Double-sided adhesive tape |
-| Spade connectors |
-| Shrink tube |
-
----
 
 ## 🛠️ Assembly 
-Now for final assembly. This is all very simple and I ran into no issues. 
+All that remains is to do final assembly. This is all very simple and I ran into no issues. Here is a **wiring diagram** of the circuit.
-
-- Applied double-sided adhesive tape to fasten the battery enclosure to the box
-- Soldered on spade connectors to wires between switch and battery
-- Installed inline fuse
-- Sealed the power port and switch mounting holes with silicone
-- Removed the battery enclosure lid since the battery terminals were ≈ 1 mm proud of the battery box lid. The battery box would still close, but it was straining the plastic and the weather sealing would be compromised.
-
-Here is a **wiring diagram** of the circuit.
 
 {{< image src="images/bicycle-headlamp-wiring-diagram.svg" >}}
 
@@ -124,17 +107,17 @@ Here is a **wiring diagram** of the circuit.
 | SW1 | SPST Switch |
 | LED1 | 48 W |
 
+- Applied double-sided adhesive tape to fasten the battery enclosure to the box
+- Soldered on spade connectors to wires between switch and battery
+- Installed inline fuse
+- Sealed the power port and switch mounting holes with silicone
+- Removed the battery enclosure lid since the battery terminals were ≈ 1 mm proud of the battery box lid. The battery box would still close, but it was straining the plastic and the weather sealing would be compromised.
+
 I strap the battery box to the rear cargo rack with hook and loop straps. 
 
 That is all.
 
---
 
 ## 🚴 Test Drive 
-All that remains is the test drive.
-
 {{< image src="images/headlamp-night-test-drive.jpg" >}}
 
-🎉 **It works!**
-
-✅ Done.