December 1st, 2022

Snowflake Star Christmas Lights

Here are the outdoor Christmas decorations that I made this year. Each star is made with 4 ea 1 1/4″ x 24″ x 1/4″ wood slats and 4 strands of lights each having 20 mini lights. I decided on 20 light strands so that each section of the star would use the entire stand and avoid the complication of trying to make the strand wiring jump from one section of the star to another mid strand. I purchased the light strands from the dollar store for $1.25 each.

To start creating the stars, I used a scrap piece of pegboard as template. On standard pegboard, the holes are spaced apart 1″ on center. I considered making alternate templates with the holes farther apart, but the wire spacing between the between the bulb sockets on the strands that I had would not really support this. After enlarging the holes so the light sockets would fit snugly, I inserted all the lights in the strand while leaving an open hole in the center. This seemed like it would work, so I proceeded to use the template to drill the wood slats that would become the stars.

Before drilling, be sure to do several test holes in the material that will be used for the star sections to find the drill bit size that allows the bulb socket to be snugly pressed into the hole. The center hole should be 1/4″ to fit a carriage bolt that will join the star sections together.

After drilling all the slats for the stars, start assembling the star by pressing the bulb sockets into the holes of the first section. For the two bulbs on either side of the center hole, press the sockets all the way through the hole. Now use hot glue to secure the all of the sockets except the two in the middle to the back of the slat.

For the second section, use hot glue to attach two or three washers around the center hole on what will be the back side. Then pass the section under the wires at the center of the first section. Insert a 1 1/2″ or 2″ carriage bolt and secure it temporarily with a nut.

The lights can now be added to the second section. Be sure to tuck the wires down on one side of the washers at the center.

Now remove the nut and place the 3rd and 4th sections into the carriage bolt making sure to tuck the wires down to the side of the washers. Secure the all the sections together with a washer and nut.

The remaining strands can now be added. The holes on either side of the center will be partially obscured by the first two sections so it may be necessary to drill the holes again at an angle so the sockets can be inserted. After all of the sockets are inserted, they can be secured with hot glue.

Now on the front side, press the lights around the center of the first two sections down as far as possible and secure with hot glue.

To finish the star, I trimmed the extra length off the ends of the star sections except for the one that was to be the top. For that one I left around 2″ of material above the last light and then glued a doubler piece on the back side. Once the glue dried, I drilled a 1/4″ hole to use to insert a wire to hang the star. Cable ties were used to tidy up the extra wire leading from the stacked plugs.

June 30th, 2021

July 4th Mini Flag Stands

This a quick project that can help you use up some of your small scraps of hardwood. During this time of year there are lots of inexpensive small decorative flags in every store. The small ones seem like they are always used by sticking them in the ground. But a small block of wood with a hole drilled in it makes a great way to display them indoors.

I started by cutting up my scrap hardwood pieces into cubes. The smallest usable size seems to be about 1 1/2″ x 1 1/2″ for heavier woods like oak. Below are my first prototypes. A 13/64″ hole was drilled in the center but not all the way through.

I probably could have just stopped here. But the wood cubes looked like they needed something else to smooth some of the sharp edges. So I decided to cut a 30 degree bevel along all four sides of the top.

For finishing, I used stain and clear spray polyurethane on the oak pieces and red, white & blue spray paint on the maple pieces. Here are some pictures of the finished stands:

December 12th, 2019

Repair Power Supply for Nortel Norstar Phone System

If you have a Nortel Norstar 3×8 or 6×16 phone system that stops working, it is probably the power supply that is faulty. I have a system that has been in operation for over 18 years that recently stopped working. After a storm, the arrow indicators on one of the phones were flashing and there were no other signs of life. I initially thought that the KSU was fried because the voltages on the power supply tested good, so I purchased another old on ebay. But when I hooked it up with my original power supply, the phones all were still not working. So I put the original one back in and plugged it in with the ebay power supply and it immediately came back to life. I decided to see if I could fix the original power supply and I pleased to say that it now works fine after spending about $12 to replace two capacitors.

The part numbers on the power supply are:

8305-315-419E
A0365495
NT5B0505

Start by opening the case. The two halves of the plastic shell are fused together. Insert a screwdriver in the seam and start prying the case apart. On mine, the plastic weld was starting to fail so I was able to pull the two pieces apart without breaking them.

The view with the cover removed:

It look like one of the capacitors had bulged:

Time to replace some capacitors. Start by removing the frame from the bottom part of the case.

Now remove the two clips that are holding the voltage regulators to the heat sink.

Now the circuit board can be removed from the heat sink. The ground wires are riveted to the heat sink so it will still be tethered to the board. In this picture I have de-soldered and removed the two main capacitors.

The board with the capacitors removed.

Next I cleaned the glue and flux off the top of the board as much as possible.

I broke the small black spacer cleaning the board, but replaced it with a computer motherboard standoff clip. I think it is mainly an alignment pin for assembly so it probably could have been left off.

Lets take a moment to check the old capacitors:

The first one is only showing 4969uf instead of the rated 6800uf (27% loss of capacitance).

Now the other one. It only has 1161uf instead of the rated 15000uf (92% loss of capacitance). No wonder the phones didn’t work!

And now the replacements… I used Rubycon MXG series with the same values as the originals (6800uf at 35v and 15000uf at 16 volt).

Replacements installed. Be sure to match the polarity properly. The negative side of the capacitors with the stripe should face inward.

Another look with the heat sink clips re-installed. Make sure the insulator pads are still in place behind the ICs. But wait, something looks funny. Look at the capacitor polarity stripes compared to the before picture.

It looks like someone soldered the capacitor backwards at the factory. This is very bad for capacitors and would typically cause immediate failure (with bulging of the top). But somehow my system worked for 18 years despite this! So I am going to say that these systems are basically indestructible.

Now with the capacitors replaced. Lets check our work. The 15 volt rail looks good.

And the 5 volt rail is spot on.

Lastly I glued the case back together with model glue and clamped it while the glue dried. I used model glue because it does not have fumes that make a white spots on black plastic like super glue does. I think this power supply is now good for another 18 years.

Parts used:

Rubycon MXG 6800uf 35v volt 25mm diameter – DigiKey p/n: 1189-3907-ND

https://www.digikey.com/products/en?keywords=1189-3907-ND

Rubycon MXG 15000uf 16 volt 25mm diameter – DigiKey p/n: 1189-3863-ND

https://www.digikey.com/products/en?keywords=1189-3863-ND

July 24th, 2018

A Bright Idea

I saw this a while ago on one of the woodworking sites and decided that I needed to build one. It is light box with an old fashioned Edison bulb. It is a fairly simple project requiring just one piece of wood, a light socket, a dimmer and a bulb.

I made my light box out of a single piece of red oak. I purchased a 1″ thick board to have a thicker base and then planed the side pieces down to 3/4″. The dimensions are 8 3/4″ wide x 9″ tall x 5 1/2″ deep.

After cutting the base piece down to size, I marked the center of the board and drilled a 1″ hole approximately 3/4″ into the 1″ base. I drilled a 9/32″ hole through the side for the cord to go through. The socket was located on the base in order to pre-drill the mounting holes. I used 1″ screws in the porcelain socket that only protruded 1/4″ into the base so as not to interfere with the wire channel.

Here I slipped the 9/32″ drill bit into the hole for the wire in order to mark the side piece and continue the hole through the side. The box was then glued together using biscuits at the top.

The finished piece with socket and dimmer installed. I used an inline dimmer with a woven cloth covered cord. It can be purchased here: http://a.co/cZ6Hwu2. The socket can be found here: http://r.ebay.com/giCcTj.

The finish is gun stock wood stain and one coat of spray polyurethane.

December 16th, 2017

Kids Workbench

I made this kids workbench as a Christmas present for me niece. I found the plans for it here: fixthisbuildthat.com/diy-kids-workbench-plans/

The bench is 24″ high at the work surface, 17 1/2″ deep and 41 3/4″ tall. It is made out of select pine 1×4 and 2×2 boards with an MDF top, shelf and pegboard. The joinery is all done with pocket screws. The finish is tung oil.

November 1st, 2017

Halloween Zombie Apocalypse

Here is my yard haunt for 2017. I have done a miscellaneous display for the past couple of years but this year I finally came up with a theme. The house was turned into a zombie containment lab with the zombies trying to get out.

My display was somewhat abstract with lighting and sound creating most of the effects. I started putting out props several days leading up to Halloween to tell the story that the house was being transformed/taken over by the zombie containment activities.

The elements:
1. Lighting – Green flood lights in all the windows and 4 DMX controlled LED PARs slowly alternating from yellow to green with the occasional strobe. Leading up to Halloween the green lights in the windows faded on and off slowly to indicate something was building up.

2. Driveway – Lighted signs warning of zombies inside along with a motion activated scoreboard buzzer combined with blinking stage light with radiation symbol gobo.

3. Sidewalk – Motion activated store bought hanging zombie prop and atmosfearfx zombie apocalypse dvd projected in the front window. Also a homemade control panel that appeared to be ripped off the wall was made to flicker via a florescent starter.

4. Front door – An industrial control panel made from plywood and electrical parts (indicator lights, meters, knobs, etc.). When the door bell was rang the store bought electrical box prop mounted on the side of the control panel was triggered along with a strobe light inside the front door.

5. Miscellaneous – Mr. Cool fog machine, a few random severed limbs, ‘caution’ tape, a 50 gallon blue drum, and some other random warning signs.

July 18th, 2017

Wine Themed Silent Auction Items

Here are some items I made for a recent silent auction at a wine tasting held for charity. Some of the items I have made before, others I made for the first time.

The wine rack from a single 1x6x6’ mahogany board from the home center. The interior cubbies are 3.5”. The finish is wood stain and two coats of tung oil.

Info on the Cork trivets is here: https://www.lobstein.org/2013/10/cork-trivet-frame/
Info on the Cork shadow box is here: http://lumberjocks.com/projects/37825
Info on the Wine bottle balancers is here: http://lumberjocks.com/projects/76977

May 29th, 2017

Bookshelf Made From Pine

I recently built a bookshelf for my great room after analyzing the design of various bookshelf projects on the internet. I settled on a simple interlocking board design and adapted the dimensions to fit my space.

The shelf is constructed from a total of 16 1×6 x 8ft select pine boards that were biscuited and edge glued together to make the 5 shelf boards and 3 uprights. The boards were glued together leaving a 3/4″ notch at the appropriate locations to allow the opposing boards to interlock, forming the shelf. Below are the cut dimensions for the pieces that were glued to the long board represented by the total length measurement. The 0.75″ measurements represent the gaps that were left to interlock with the perpendicular board.

Horizontal shelf board (5ea):

Overhang:  12"
Rail 1:  0.75"
Shelf:     23"
Rail 2:  0.75"
Shelf:     23"
Rail 3:  0.75"
Overhang:  12"
Total = 72.25"

Vertical shelf standard (3ea):

Overhang:  12"
Style 1: 0.75"
Shelf 1:   16"
Style 2: 0.75"
Shelf 2:   16"
Style 3: 0.75"
Shelf 3:   16"
Style 4: 0.75"
Shelf 4:   16"
Style 5: 0.75"
Floor:      4"
Total = 83.75"

In the picture below is one of the horizontal shelf boards with the biscuit slots cut, ready to be glued together.

You can never have enough clamps…

The finished boards up for a test fitting prior to painting. I cut 1″ off the front edge of the upright boards to give the shelf less of a boxy look. I also cut a notch at the bottom to allow the shelf to fit around the baseboard when flush with the wall.

The finished shelf with two coats of semi-gloss latex enamel paint.

January 24th, 2017

IKEA Cabinet Modification

IKEA can be intimidating. The store is humongous and the options are seemingly endless. It takes some study to narrow down the options to find what you need. In my case I needed a laundry cabinet above the washing machine. This cabinet will store the detergent and other laundry supplies. While the big box home centers have stocked a plethora of options for oak and white thermofoil/melamine kitchen cabinets, there was a big problem. In test fittings at the store, it became obvious that none of the currently available laundry detergent dispenser jugs will actually fit in a standard 12″ deep upper cabinet.

I thought about custom building a cabinet but it seemed like there should be something commercially available for this purpose. Meet the SEKTION cabinet line from IKEA.

The SEKTION line of cabinets turned out to be exactly what I needed. To start with, SEKTION upper cabinets are all 15″ deep instead of the standard 12″. I my case, I needed a single door upper cabinet. Within this one variation of cabinet, there are 17 different height and width (12″, 15″, 18″, 21″ & 24″) options available. There are also many different choices in door styles available. I ended up choosing a 18″ W x 30″ H cabinet with the very basic white ”Häggeby” door.

After obtaining a pick ticket and paying at the store, I went to the pickup area and got a nice tidy bundle of packages brought out to me on a cart. Since the cabinets are modular, the individual components are picked that make up the finished unit that is desired.

The only issue now is assembling and mounting the cabinet. It turns out there is a small problem that must be overcome. The cabinet system is designed to be mounted on a hanging rail system. To make the installation easier, a metal hanging rail is screwed to the wall studs and the cabinets are hung from it. The only downside to this system is that it holds the cabinets out from the wall slightly. In my case, I decided not to use the hanging rail system for just one cabinet. This required some modifications to the cabinet box as seen below.

To avoid using the hanging rail system, nailer strips needed to be added to the top and bottom of the cabinet box. I used 3/4″ x 1 1/2″ melamine strips to accomplish this. I cut biscuit slots in the strips so the #20 biscuits would align with the groove in the cabinet that was intended to accept the back panel. I then applied a melamine edge banding to the two strips before cutting new grooves in the top to accept the back panel. The biscuits and then glue were then applied to secure the nailer strip to the top and bottom panels of the cabinet.

After the glue dried, the cabinet was assembled per the IKEA instructions (cam locks, cam screws and dowels) after cutting the back panel down to the size needed (26 1/8″) to fit between the newly installed nailing strips.

 

Below is the completed cabinet with the door installed after screwing it directly to the wall studs through the newly installed nailing strips. It holds all of my laundry supplies quite comfortably.

January 18th, 2017

Customized JAMMA switcher for 2-in-1 light gun arcade

So here is the dilemma… You buy a video game cabinet and then decide that just having only one game in it does not satisfy your inherent need to make it contain more than one game. And what if you cabinet was a ‘gun’ game for which that type of arcade machine is at a distinct disadvantage for using with MAME type emulation? Well there ought to be a way to switch between multiple game PCBs right? Well yes there is, you can get a switcher for just this purpose… But, after implementing such a setup, I don’t recommend it. Read on for more details….

IMG_20151210_122813

Here is my Lethal Enforcers II arcade machine that I purchased many years ago. Some point after I acquired it, I decided to purchase the PCB for the original Lethal Enforcers arcade machine for which I remember playing so much in the college dorm laundromat. For years I got by just having the 2nd PCB mounted to a tray inside the cabinet and swapping the JAMMA and gun connectors when I wanted to switch games. This was fine if just a little kludgy.

But it just so happens that there are products intended to solve the problem of switching all of the wires in the JAMMA harness between PCBs that sort of work. Here is the one that I purchased:

img_20151103_192231

It seems like it should be a straight forward task to switch between two game PCBs, but it is not. To make wiring a video game cabinet a standard practice so that a different game board could be swapped into a cabinet without changing the wires, the JAMMA (Japan Amusement Machine and Marketing Association) connector was invented. It standardized the pin-out on game PCBs and the associated wiring to components in the arcade cabinet. There any many different types of signals in play on a JAMMA harness. Including:

  1. Power: +5v, +12, -5v (not used by most PCBs) & Ground
  2. Sound: Mono “+” and “-” speaker output
  3. Video: Red, Green, Blue, Sync and Video Ground lines.
  4. Contol Inputs: Joystick (Up, Dn, L, R), Buttons (Shoot, Start), Coin Trigger, etc. [for two players]

In addition to the standard JAMMA harness, this cabinet also has extra connectors for the two optical guns and stereo speakers. So how will this switcher handle that? Not very easily it turns out.

Let’s look at the switcher as it arrived:

IMG_20151103_192329

IMG_20151103_192339~2

The basic theory of operation for this switcher involves using relays and diodes to switch back and forth between the two games when the button on the wireless remote is pressed. The relay on the right of center alternates routing the +12v and +5v power feed between the PCBs. Note that this switcher does not switch the -5v signal between PCBs, instead it leaves those pins unconnected. This is not an issue since most PCBs do not use the -5v power feed. The second relay alternates routing the speaker connection between the PCBs. The remainder of the connections (video and control signals) are tied together from both PCBs to the cabinet JAMMA harness. The two rows of diodes prevent signals from one PCB from from entering the opposing PCB. Since only one game is powered up at a time, the arrangement works. But there is a problem, if you look closely at the spots between the pin connectors, there are spaces for eight diodes that are not installed. Unfortunately these missing diodes were intended to separate the video signals (Red, Green, Blue & Sync). As a consequence, it can be said that this JAMMA switcher fails to work as advertised. Strike one against the idea of easily switching between PCBs in the same cabinet.

On to the modifications! Hint: Lots of relays.

IMG_20151112_192752

Six DPDT relays to be exact. By using relays, the signals for Video (Red, Green, Blue, Sync), Stereo speakers (L+, L-, R+, R-), and both of the optical guns (trigger and optical sensor) are able to be switched cleanly across both PCBs. The +12v pin going to the PCB #2 JAMMA connector is connected to the coil of all of the relays. So when game #2 is active, all six relays are switched on and the above connections are switched over to PCB #2.

Also note that the +5v and ground wires that power the optical sensors for both guns are not switched through the relays, instead they are connected directly to constant +5v and ground. This arrangement powers the guns’ optical sensors directly from the power supply and not through the switcher. Lastly of note, the video ground pin for both JAMMA PCB connectors were separated from the power supply ground and tied together. So the video ground pins of both PCBs are jointly connected to the monitor and nothing else. After soldering all of the various connections to the original switcher and creating jumper cables for the guns and speaker connections, this monstrosity is now complete. Final score: power, start buttons, service switch and coin triggers are routed through the switcher’s relays and diodes and everything else including video signals, optical gun signals and the stereo speakers are routed through the add on relay board.

Here is the finished product:

Here it is connected to PCB #2 (Original Lethal Enforcers). The two gun connectors are on the left side and the stereo speaker connector is on the right side.

Here is the switcher and relay board installed in the cabinet:

IMG_20151120_113209

The PCB original to the cabinet (Lethal Enforcers II – The Western) is in the background. The second PCB (Lethal Enforcers I) is in the foreground. The game select button was installed in the front of the cabinet next to the coin door.

Video of the switcher in action:

Final thoughts:

While this was quite a bit of work, the final product does work pretty well in my case. Switching between the two games in my cabinet is seamless. However given the low quality of JAMMA switchers that are still available for sale, I would not recommend purchasing one unless you are prepared to solder on it.

The only small issue that I have with the final product is the monitor. Monitors in these older game cabinets have manual analog controls that need to be adjusted to produce the best picture for the game that was installed in the cabinet. Since only one game was installed at a time, the picture could be properly centered and the brightness and contrast controls set just right (very important on an optical gun game). When switching between two games, the picture settings need to be a compromise between the two. In my case, the brightness setting needed to get reliable gun hits in LE II caused the picture to be somewhat washed out in LE I. But I can live with that. If you are thinking about doing a 6-in-1 light gun cabinet like in the link below, note that it could be very difficult to get a good picture on all six games without having to adjust the monitor every time the game is switched.

GAME OVER

Further reading on JAMMA switchers & Light gun games:
https://forums.arcade-museum.com/showthread.php?t=271012