And one last item about the drawings. In reading ahead in the assembly manual I found that a tiny bit of the wiring that I did is actually outlined in the assembly manual. This is not a big deal. But if anyone happens to use my drawings in the future to rewire a Citation don't be confused when you return to the manual and find some wires specified in the instructions already attached to the switches.
With the factory wiring out of the way I can now return to the Assembly Manual. I left off towards the top of page 23 so let's pick it up from there. Things are going to be pretty straightforward from here.
Page 23 outlines the steps for wiring the bass, treble, rolloff, and low cut switches. There really isn't much additional commentary I can make. These switches are the easiest to wire and consist mainly of attaching a few variously colored wires. There is a lot of striped wire used for these switches, which I labeled using the method I have described previously.
The only decision I had to make was whether to use one or two labels for the striped wiring. Some of the switch wires end up attaching to the terminal boards and others attach to other switches. In general, if a wire went to one of the terminal boards I used two labels, one at each end. This made sense as these are usually longer wires. The wires that attach to other switches are usually short and a single label wrapped around the middle of the wire will suffice.
The striped wires that run from a switch to the terminal board present another unique problem. To keep the inside wiring neat the wires from all the switches are collected into a number of bundles. These bundles are then tied together and routed neatly around the chassis. It will be next to impossible to neatly bend a teflon coated wire at the point where a label is attached. This means I have to take extra care in where I attach the labels.
I solved this problem in two ways. First, I only attached the switch end label at this time. I will attach the second label later when I am tying the wires together and routing the bundles to the terminal boards. Second, I have the luxury of having another Citation I available. This allows me to look at where a wire is going to route immediately as it travels away from the switch lug. Based on this I can locate the first label in a good spot that will minimally interfere with any wire bends. If you don't have a second Citation unit for reference you'll have to look at Citation I pictorial drawings.
The wiring of the mode switch is described on page 24 and is the next step up in complexity. There are bare wires, insulated wires, and a couple of 47K resistors that need to be attached. Still all relatively simply.
On the bottom of page 24 begins the function switch wiring. This one is a beast and the instructions for this one switch cover two full pages of the manual. This switch not only has many more wires than any of the other switches, but at least half of those wires are shielded wires. I only have one picture to accompany today's post and this is it.
This picture represents the preparation of shielded wire. Pictured are a short ruler for measuring the end for stripping, a wire cutter/stripper, a razor blade, a pointed pick (that came with a soldering kit) to "unbraid" the braided shield, a coil of shielded wire, and shielded wire samples in various stages of preparation. Note that the wire pictured is what I described in an earlier post. It is single conductor 22 gauge stranded silver coated wire with a Teflon jacket. It is then wrapped with a braided silver coated wire shield and covered with a Teflon tape jacket. This wire was purchased from a vendor on eBay.
An appropriate length of wire is measured (with a longer ruler not pictured) and cut. Using the short ruler I follow the instructions in the Citation manual for how much outer insulation to strip away. I use the razor blade to cut through just the insulation, being very careful not to nick the braided shield. I found that in addition to cutting a "belt" around the wire I also had to cut a slit the length of the wire in order to remove the insulation. I first tried to strip the outer insulation using the wire strippers. This didn't work as the stripper either didn't cut all the way through the insulation or it cut some of the wires in the shield.
I then use the pick to unbraid the shield wires. When the shield is unbraided back to the outer Teflon jacket the individual shield strands are carefully pulled together, straightened as best as possible, and then twisted tightly. This is a time consuming task. It doesn't take all that long to unbraid a single wire end. But when you have to unbraid each end of the wire and you then multiply that by all the shielded wire used in the assembly of the Citation I you will find that a lot of time is spent simply unbraiding the shield.
A measured length of the inner Teflon jacket is then stripped away. Both wires, the shield and the inner conductor, are lightly tinned. Lastly, a colored label is attached to an appropriate location near the end of the wire (as seen in the picture). Note that when using shielded wire you even have to use labels for solid colored wires, not just the striped wires.
The wiring of the function switch is not particularly complicated. It's simply messy. There are a ton of wires to attach and it quickly gets very crowded. Clear Teflon spaghetti tubing of the appropriate diameter is used to insulate the exposed shield wire in place of the original Citation kit black insulation.
I wish I had taken a photo of the completed function switch to give an idea of how unwieldy it is. Of course, cable ties will be used to gather the wires together in bundles for neat routing around the chassis. But until then you have a Medusa's head on your hands.
That completes the rotary switch wiring. Next time I'll pick up with the wiring of the front panel.
Total Time Spent: ~8 hours
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