 It has been just over a year since I restored my first Doctor Who (Bally, 1992), so I guess it is fitting that I'm now finishing up restoring my second. My first Doctor Who was purchased by a local collector and, since I sold it, has been treated to a new layer of clearcoat on the playfield, LEDs, a USB TARDIS, opto improvements, and a host of other upgrades. Just when you think there's nothing else to do to a machine, someone does some more! I'm glad it made its way into good hands. There was a reason that I restored this machine second. This machine was in much poorer shape than the first and required a bit more work to get it into a presentable state. But with the experience of the first Doctor Who restoration, and now with some additional experience from the two Fish Tales restorations, I thought I may as well finish dealing with the doubles of all my machines and get this Doctor Who back into action. Initial condition report (click on sections below to view details) Cabinet
Average condition overall.
Above playfield
Average condition overall.
Under playfield
Average condition overall.
Electrical
Good condition overall.
The playfield looked relatively similar in condition to the first Doctor Who, so check out the disassembly images from my first teardown for an idea of how things looked. A few images of this machine are in the gallery below. At this point I have to reiterate how useful Faz's guide is for disassembling and troubleshooting the mini playfield. While I knew the mini playfield inside-out from the last restoration, I still referred to his guide multiple times to double-check all of my work. Download a copy here: 
Other than that, it was a pretty uneventful teardown. After disassembly, the game went through my standard restoration process to get it playing and looking like new. During the restoration process, I dealt with a number of issues, described below. Tips & Troubleshooting (click on sections below to view details) Dalek topper missing head and dome
This machine came with half a Dalek topper. Unfortunately I never snapped a picture, but it looked almost exactly like the image below, with the bottom half bent to the side and the head totally missing. The transparent dome, of course, was also non-existent. I can only assume the dome got smashed while the machine was out on site and the Dalek was bent during an attempt to steal it. It was a shame, because my first Doctor Who had a perfectly intact topper.
Dalek without a head! Image courtesy of AAAR pinball.
Interestingly, the bend in the Dalek toppers can actually be fixed with a little heat and manual bending according to AAAR pinball. I didn't end up trying to fix my Dalek as even if I had managed to fix the deformation, I was still missing the head. I actually found a second hand Dalek on eBay after I finished restoring the game. While it was damaged, it was miles better than the headless zombie I had. Up until this point, I had actually taken everything off the top of the backbox because the broken topper looked so bad. The flash lamp protruded from the top of the Dalek body and blinded you if you looked up at the wrong time. At least with the new Dalek, the flash lamp would be covered. The nose was still missing, and one of the red domes was dented, but at least it was a little more complete. Many thanks to Barry at Able Amusements for the topper! 
New (less-damaged) Dalek for Doctor Who.
At this point, I was still missing the clear plastic dome that covers the Dalek (part no. 03-8710). This part is basically unobtainable. One solution is to use a topper dome from Fish Tales or Whitewater (part no. 03-8653, from PSPA, RTBB). This one is larger, but it fits on the machine and is readily available. I didn't like the look of the larger dome, so I left the Dalek without one altogether. Here's hoping someone reproduces the correct dome in the future. Playfield glass channel/trim broken
The plastic channels for the playfield glass (part no. 03-8091) were broken on both my first and second Doctor Who games. Not sure why. I installed a replacement glass channel and cut out a small section to make space for the safety switch. As far as I know, original channels with the notch already cut out are not available. Incorrect top flap installed on mini playfield
The mini playfield had an incorrect top flap installed which had ripped and torn in several places. The same weird glue had been used on this machine as on my first Doctor Who, and had been spread all over the mini playfield. I removed all of this crap and treated it to a full rebuild including a clean of the motor gearbox and new grease on all of the bearings. Since I've rebuilt two of these mini playfields now, I've written up a separate blog post on the process of cleaning and repairing them.
Heavy wear to mini playfield and main playfield edges
The next big job was fixing the top edge of the playfield adjacent to the mini playfield hole. There was some fairly severe wood damage which included chipping of the playfield all the way to the top edge of the "7" insert. I sanded this area to rough it up before filling it with Selley's Knead It. Then it just needed a sand to smooth it back out and some paint. This area wasn't too hard to paint as it just needed three colours: yellow, red and black. The small strip of blue and red around the 7 insert was to be covered by a Cliffy protector later, so there was no need to repaint those areas.
The yellow was the first area to be painted. We used Createx Opaque Yellow with a touch of Opaque Red to create the right shade. For the black, we used Opaque Black. The end result looked pretty good and the colours mached quite well. It was hard to see the area had been repaired unless you were up close to it.
Time Expander inserts slightly sunken. Edges showing.
One of the issues with inserts of games such as Doctor Who is that they have black borders. And when you have inserts that are very closely packed such as those in front of the Time Expander, the excessive heat tends to make them sink into the playfield slightly. The inserts on this game had not sunk very much, however, they had moved enough for the insert edges to be visible and this made the area look ugly. Fiona went over all of the inserts on Doctor Who with black paint (Createx Opaque Black) around the insert borders. This really makes them pop after the playfield has been cleaned and new lamps are installed in the inserts.
Ball guides missing from the mini playfield
One of the more frustrating parts issues I had to deal with was missing ball guides on either side of the mini playfield (part no. 01-106044-L and 01-10644-R, two in total). Missing parts are annoying at the best of times, but it is a real pain when they are parts that are almost impossible to source. Such was the case with these ball guides, and I had resorted to using rubbers in their place until I found a suitable replacement.
It soon became clear that if I wanted to have these ball guides, I would need to make them on my own. This was my first attempt at fabricating a metal part, and without a template, I needed some measurements. Many thanks to Dave at Aussie Arcade for the preliminary measurements! 
The next task was to source materials. For this I made a trip to Bunnings to see if they had anything suitable. Thankfully, they did. Metal Mate have various lengths of angled aluminium, one of which was the perfect size for use as a ball guide. I used this product and cut it to size as necessary. After cutting, just drill the screw holes and deburr the edges and you should be good to go.
Overall, I was very happy with the result, even though any metalworker can tell I'm no pro. It looked miles better than rubber rings and was difficult to tell apart from the original steel. As with any part that requires measurement and cutting, measurements such as those above should be treated as preliminary guides only. Always measure the same distances on your own machine to see if they match. Unfortunately, I didn't do this, and ended up having to enlarge and relocate some of the screw holes because they were in slightly different positions on my machine compared to the template measurements. They are now nice and stable, and the player is none the wiser. Time Expander plastic cover broken
The Time Expander cover (part no. A-15582) is almost always broken at the screw holes, especially on the edges above the standup target. I installed some washers under the screws to give it some stability. The Time Expander cover is now actually being reproduced by Freeplay40, so there are new ones available.
Washers installed under the Time Expander cover.
Mini playfield had motor movement direction errors
The mini playfield movement was much better after a rebuild and clean. The slant was gone and movement was pretty smooth, but I started seeing some weird behaviour whereby the motor would move counterclockwise, but not clockwise. Clockwise and counterclockwise movement is controlled by current going from the power driver board, through the bi-directional motor driver board, and to the motor, reversing polarity to reverse direction when required. With no clockwise movement, it couldn't move back down to the starting position after raising. When it raised to the second level, it dropped slightly so the mushroom targets could not be hit properly. When I tested the movement in test mode, I noticed the playfield moved slightly at the end of each clockwise test. Weird, huh? Here's a video of the problem in test mode:
I didn't notice anything physically wrong with any of the mini playfield or associated components, but I remembered something that I had "fixed" several days before. I had double checked the game's wiring to make sure it was all OK. Looking at the board schematics in the manual, I saw that pin J1-1 on the bi-directional motor driver board was meant to lead to pin J122-3 on the power driver board. Respectively, J1-2 was meant to lead to pin J122-4. 
Bi-directional motor driver board wiring as it appears in the Doctor Who manual.
On my game, these wires were reversed. The wiring on the bi-directional motor board side was correct, but on the power driver board, J122-3 was blue-orange, and J122-4 was blue-yellow. So, I "fixed" the wiring by swapping the wires around so they led to the correct pins. That's when I started seeing the issues with motor movement. Strangely, the correct wiring for J122 is actually printed on the manual page for the power driver board, contradicting the wiring scheme later in the manual (above). Go figure! So remember: the wiring in the image below is what your game should be. After reconfiguring the wiring to the way it was before, the playfield moved normally. So the moral of the story is: don't fix wiring issues that aren't actually issues! The manual is sometimes wrong, which is not helpful when you are trying to verify correct wiring. 
Power driver board wiring as it appears in the Doctor Who manual.
Slingshot plastics broken
New slingshot plastics (part no. 31-1681) can be bought from Pinball Center but I elected not to replace the originals. Conduit for playfield wiring destroyed
The plastic conduit for the playfield wires in the cabinet was completely disintegrated and destroyed. I bought a roll of 28mm split conduit off eBay and installed the wires into it. This conduit was a little thinner than the factory conduit but the wires fit inside without issue.
Remains of a completely destroyed wiring conduit.
Phantom switch his on mini playfield
Every now and again I noticed that hitting a part of the mini playfield body (ball guides, posts, etc.) would sometimes trigger a switch hit. There was no reason for this because it would happen when the ball was nowhere near a switch. The switch that was being hit was one of the mushroom targets on the second level of the mini playfield. But this was happening when the playfield was all the way down, and the second level wasn't even accessible to the ball. Time to investigate. As the switch hits were coming from the second level of the mini playfield, this was a problem with the optical switches triggered by the mushroom buttons. I pulled the mini playfield out of the game, disconnected the opto assemblies, and reconnected them to the game wiring on their own to do some testing. It is easy to test these assemblies when they are connected to the game as you can see whether or not they are getting the correct voltages and whether the opto transmitter and receiver are working. Faz's guide has some specific advice for testing the opto switch bank in the mini playfield. Pinwiki has a good description of how to test opto switches generally, by using an infrared camera. Following this methodology, I found that one of the opto transmitters was transmitting a very weak light compared to the others. When I inspected the emitter and the solder traces on the back of the board, I was able to wiggle it and trigger switch closures just by tapping it. This is what was happening when the ball hit parts of the mini playfield - the flaky transmitter would register phantom hits. A new opto emitter (PSPA, John's Arcade) was installed and the phantom switch hits stopped. General illumination connector burned
This GI connector was pretty badly toasted - burned right down to the terminal! This one was an easy fix; removed and replaced with a new IDC connector. The header pins were still very clean and didn't warrant replacement.
Severe burning to the general illumination connector at J120.
Dot matrix display showed artefacts
The issue with the dot matrix display turned out to be a simple one of a bad display ROM. I cover the replacement procedure in another blog post. I replaced it, and everything was back to normal. Reassembly I replaced all of the broken lamps and installed fresh black rubbers throughout the machine, including three new black flipper rubbers. I left incandescent lamps in the game. Doctor Who uses lightning flippers which are shorter than standard flipper bats. All of the bats on this game were original and came up well after a good clean. Cliffy protectors are an absolute must on Doctor Who. The mini playfield gets smashed by balls and this is why it is usually so damaged. Cliffy makes three protectors for the mini playfield and I installed all of them on this game. They help cover up repair work and protect the game in the future. The mini playfield edge should have been covered with some kind of protective cover from the factory. Unfortunately, it wasn't. Wood that is directly exposed to ball impacts will never last long! The ramp protector is also a good idea if your ramp is damaged or cracked, or the factory-installed protector is missing. You can get protectors for the lock holes, as well. There are a lot of reproduction parts available locally for Doctor Who, such as decals and parts for the mini playfield (PSPA, Mr Pinball). Prototype games were also released with a moving Dalek topper. The software to drive the Dalek is still present in the game, so you can motorise your own topper if you can get a motor and associated parts. There used to be several (expensive) kits you can buy that included everything you needed, but none are available anymore. Various people have created homebrew kits and there is enough information online to fabricate your own parts (Basement Arcade Classics, Missing Piece Technologies, Pinball Toys UK). There are various other homebrew guides, so search around. I grabbed the same custom instruction and pricing cards from Pinball Cards that I used on Doctor Who 1. Please consider donating if you download any cards from his site.  Conclusion I can only echo some of the comments from my first restoration. Doctor Who is still one of the most painful machines to rebuild and restore properly. Nevertheless, this one was an even better learning experience than the first. I had to deal with new issues in this machine that I haven't dealt with to the same extent with previous restorations, including serious playfield repair and some tricky playfield issue troubleshooting. I was pretty chuffed with myself for figuring out the issue that was causing the mini playfield movement direction errors, as well as the method I used to track down the phantom switch issue. This just reinforced my opinion that you need patience and good critical thinking skills to track down these issues quickly. Admittedly, sometimes I have neither, so some of these issues take a lot longer to fix than they would with someone else! While I still hate the mini playfield, I have an increased appreciation for the game. Once the game is cleaned and working properly, it is actually a lot of fun to play. The Dalek jackpots are satisfying shots when you hear the clunk of the ball when it enters the mini playfield holes. I had a good time test playing this machine until I finally decided to sell it, as I still needed to make some room. I eventually did find a buyer for this machine - from Canberra - who drove up and picked it up himself. He was very happy with how it looked and how it played. I hope he is still enjoying it!
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