posted 03-22-2006 10:00 PM               

I have c-a-r-e-f-u-l-l-y rotated one of the indicators to find that it uses standard GE327 28V aircraft lamps. The bulbs all seem to be present. As you can see from the back, the wires have been cut off in such a way that I would have to replace the wires to power this unit up.

My concept with restoring this is to mount it in a small display case, with a photo of one of the Firing Rooms lining the inside of the case as a backdrop. I was thinking of constructing a small logic board with a timer to light the indicator lights in the order that they would have lit during the pre-launch countdown. To do this, I'd have to re-wire the back of the panel, meaning I'd have to replace the original wires. These are all on the outside of the panel and it looks very straightforward. I wouldn't have to do anything to the "guts" except to replace any non-working lamps.

My questions are:
(1) Would replacing the wiring bundle diminish the value of the item? Should I just leave it alone?

(2) What would you recommend for cleaning the metal case? It's in pretty good shape but a little dirty.

Any other thoughts on restoring this little item? I'm very excited about having this piece of history and I want to treat it with respect.

Thanks!
Jonathan

[This message has been edited by ilbasso (edited March 22, 2006).]

posted 03-22-2006 10:32 PM               

Artifacts are different. We need to remember that we are only their temporary custodians and we have a responsibility to protect and preserve these pieces for future generations.

Whether restoring a small firing room panel or a monstrous Saturn V, the first concern should be preserving as much of the original artifact as possible. In this case, if the original wiring can be removed in such a way that it could be reattached later (if desired), that would be ideal. You might attach a sticker or decal to each connection point on the wire so that its configuration can be maintained.

In the scheme of things, the above might be a tad overkill. The wires were, after all, already cut. But at least this way, you can attempt to reverse your rewiring if you desire to do so later.

I'll let others more experienced (and there are some here) comment on cleaners and other techniques. I'd only ask that when you have the final presentation ready and lit, please share some photos here!

posted 03-23-2006 05:40 AM               

The bundle that is snipped off looks long enough to be able to strip back and attach in line splices to re-power the light panel.

Pardon the pun, but this would not be rocket science. Leave the original wiring connected. I have an aircraft known as a Globe Swift built in 1946 and about 99% of the wiring in it is original and still functioning.

posted 03-23-2006 07:44 PM               

2. The light bulbs. I'm tempted to say put the originals in a waterproof bag and actually keep them in the base of the display. If you have burned out bulbs (which will happen as a display) at least they will not be the originals.

As for the case I would not use anything abrasive or chemically harsh. Just a rubbing and blotting first with a very dilute soapy water then blot with clear distilled water and a soft towel. Dry very thoroughly.

[This message has been edited by kyra (edited March 23, 2006).]

posted 03-23-2006 09:12 PM               

I am thinking of using a shadow box with a false back or a platform in the bottom, with the power supply and logic board out of sight. I was going to use this picture as a background for the display:

posted 03-23-2006 11:23 PM               

Here's another thought. It looks like there are only 10 or so panels that would have been illuminated. Looking at some of the wiring it's not obvious that the panel was wired with a common ground, but you could certainly do so.

How about a series of 20 alligator clips clipped to the terminal posts? They look like they have a well shaped flange or knob on the end that you could get a good "bite" on. This way you wouldn't have to touch the original wiring at all, except to perhaps slightly bend the cut ends to remove any shorts.

BrianB

[This message has been edited by BrianB (edited March 23, 2006).]

posted 03-24-2006 05:20 AM               

Just wanted you to know that the "rocket science" comment was meant as a funny. If taken with offense, I apologize, for that is not what its intention was.

posted 03-24-2006 08:42 AM               

I like the alligator clips idea, too. That will give me a little more flexibility to change the design or upgrade the display later. I'm more of a "design as you build" kind of guy. It also minimizes the damage to the original wiring.

posted 03-25-2006 09:07 PM               

I did some research to determine the order in which the lamps on this S-IVB monitoring panel would have lit in a nominal countdown - first loading and pressurizing the hydraulic accumulator, then loading the LOX, then the LH2, checking GH2 pressure, then retracting the arm at launch.

So I came up with six discrete states (combinations) of the lighted lamps. E.g., lamps #579 would all be lit on in the first state, then lamps 2579 in the second, then 25679, etc. My problem is that I never had any instruction in circuit design so I'm having a little difficulty coming up with a simple circuit that will switch between these states. Can anyone point me to a web resource that would be of help in designing this?

posted 03-26-2006 06:46 AM               

If you look at a digital number "8", like you find on a digital watch or clock, you see that it is made up of "7 segments" Depending on the number, the decoder sends a voltage to the segment it wants lit. For example, a "1" has two segments lit in a straight line, an "8" has all 7 segments lit.

Using this, you can get 2,3,4,5,6 and seven outputs simultaneously. If you have a lighting pattern that requires 2,3,4,5,6 or 7 lights to be on at the same time, this is an easy way out. One IC on a circuit board with either a manual push button input or a clock signal to turn these on at the clock pulse frequency. Remember though, that as the circuit is pulsed, 1,2,3,4,5,6,7,8,9,0 the output will be 2,5,5,4,5,6,3,7,4 segment outputs. Hook it up accordingly or use some of but not all the outputs. The IC will come with a "pin out" diagram usually to tell you what pins the signal comes out on and the inputs go in on.

Use a CMOS type 4511 IC Driver and decoder all in one package and it has enough driver current to light led's, fluorescent or incandescent bulbs.

Read here.

Also read the info under "Basic clock sources".....Have fun!

posted 04-19-2006 09:31 AM               

First, a big THANK YOU to John Fongheiser who informed me that there are 6V equivalent lamps to the 28V lamps that this panel came with - and for supplying me with some vintage lamps. That greatly simplified things, as I can now use a D cell battery pack instead of a power supply.

Second, thanks to Fred Karst for sending me some photos from the KSC firing room display. Here's an example of one of these types of panels in situ in the Range Safety contol console. (Wouldn't it be cool to have one of these entire consoles??????)

I partially disassembled the panel, removing the frame and the metal bracket at the bottom of the unit. I couldn't remove the top bracket because the manufacturer's sticker covered two of the screws, and I didn't want to disturb it. The individual light cells are designed to rotate so you can replace the lamps, but most were stuck after 40 years of sitting in the same position. By gently separating the cells after removing the bracket, and by a couple drops of lubricant, I was able to free up all the cells so I could rotate them and insert the new 6V lamps. Each cell has space for two lamps, but only one of the lamps is wired in each cell. So, I left the existing 28V lamps in place and put the 6V lamps in the unwired sockets. I relocated the 28V lamps that were in those sockets to empty sockets in the unused cells at the bottom of the panel.

I gently opened the clamps at the front of each cell to remove the plastic inserts with the panel labels. I washed the inserts gently in a mild soapy water, dried them thoroughly, and replaced them. Then I reassembled the unit.

I left the existing wiring in place. I used alligator clips to provide power to the unwired terminals that powered the 6V lamps. I also wrapped wire to connect the center posts of the used cells to provide a common ground. The leads from the alligator clips went to a connection block.

On the metal lid of a separate hobby box that I'm using as a control/power box, I wired a set of switches to generate the lighting sequence that I had previously determined (shown in a post above).

I cut the connectors off of a spare computer cable and used the remaining cable to connect the switches to the panel connection block. I tested the setup and all works fine.