Nothing much to it. Simply unsolder all the wires from the connecting jacks. Take off the large black sleeves and retain for later use. It looks like these sleeves are simply used as wire organizers. If so, I may not reuse them. Instead, I may go with some spiral cut teflon tubing.
I also removed the short bare wire length that connected the grounds on each set of 4 RCA jacks. Be careful with the amount of heat you apply if you will be re-using the black insulators. I will definitely be keeping these and drilling them out to accomodate the new gold plated RCA jacks.
I did this work a few days ago. Now that I reflect back on it I realize that I'm going to have to figure out how to reconnect all the grounds from all the RCA jacks and do it in a neat fashion that is in line with the rest of the tidy design. It's possible I can still implement the same design, lining up the ground tabs for each jack so that I can attach a straight length of wire. On the other hand, maybe a ground lug on each strip of 4 jacks, mounted so that it grounds to the chassis is the way to go.
With the wire out of the way the next thing I did was to unbolt the choke that hangs over the terminal board. Place the bolts back on the choke as an easy way to ensure that these don't get lost before the assembly process. I flipped the choke over and let it rest on the power supply section while I continued the work.
The rest of the rest of the work is identical to what I did on the Terminal Board B side. Simply pick a place to start and dive in. Remove the components piece by piece until they're all removed. Then remove everything from the tube socket pins. I took extra care this time to make sure I didn't break off any more pins. Here's what the underside of the chassis looks like after this stage.
I'm going to leave the power supply section intact for now. The Jim McShane power supply upgrade will change the layout slightly. Because of this I want to study the original layout and compare against Jim's instructions for the new parts before I start tearing things apart.
Ok, so were there any oddities that I ran into on the bottom side? Yes, a few. In my previous post I already mentioned the switched convenience outlet that was inactivated by the long lengths of blue wire looped back to itself. You can see that again in the photo above.
The next thing I ran into was on Lug #69. There was an odd wire that was sticking up out of the lug hole and bent slightly over the top of the lug. The wire end was about 2 or 3 mm long. I applied the hot iron to the lug intending to pull the wire out with a needle nose. What happened instead was that the whole lug came loose as soon as the old solder melted. Ahhh... I see what's going on here. Someone broke the lug off and a piece of wire was used to hold the lug in place. Disappointing to find, but not the end of the world either.
Another thing I found as I began to remove parts is that many of the lugs were awfully full of wire. In some cases the post was full of wrapped wire and the resistor or capacitor was basically soldered to the very top of the lug. As I cleaned the parts off these lugs I saw that someone had simply clipped off the old part close to the post and added the replacement part. There was also a big "melt mark" on one of the black sleeves that covered the wires to the RCA jacks. I suspect that the cabling was left in place and that made it difficult to work on the terminal board so the person found it easier to simply clip the part off rather than try and neatly remove it.
The last discovery came as I got to Lug #62. Wow! This lug isn't even connected to the terminal board, but hanging in air. This looks like a repeat of Lug #69. Except in this case the person decided to not even try and reattach it to the terminal board. The stiffness of the connecting components seemed to be enough to keep this lug in place, but we'll be taking care of this during the reassembly.
With all the component parts removed I next proceeded to remove both A and B boards from the chassis. In order to keep parts such as washers and screws from getting lost I screwed them all back in to the mounting bracket. I then took the boards over to a sink and used simple drugstore grade rubbing alcohol, a toothbrush, and cotton swabs (Q-tips) to clean the boards. The alcohol dissolves the old flux quite nicely. I simply poured some alcohol on the board and scrubbed with the toothbrush. Replenish with more alcohol as necessary. I used the cotton swabs to clean more tightly around the lugs. When cleaned to my satisfaction I rinsed with a little more alcohol and let dry. Here's what the clean boards look like. Note the gap where Lug #62 should be.
Time spent on the above work: About 4 hours.
I'm not sure what I'll post about next. I have two or three things working right now. I could report on the progress on ordering replacement components. I could also start in on the rewiring of the terminal boards. And maybe a status update on the progress of recreating the Citation I Assembly Manual is in order.
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