Four Letter Word Kit Gallery

This is a rear view of the assembled board. It is a photo of the first unit used for debugging and testing, so the microcontroller is a ceramic-windowed one and two wire option jumpers have a DIP switch kludged, to the right of the 8-position DIP switch.	This is a detail of our special universal socket pads. These can accept original vintage sockets or modern socket pins from Tyco or Mill-MAX. There are 18 holes so that the tubes can be mounted from either side of the PCB.	This detail shows the Tyco socket pins mounted into the larger hole of the three on each pad. The holes are much larger than in the 2002 model, which has been superseded.	Another view of the socket pins with tubes installed in three of the four locations. The power connector is not included, but is used for in-house tests so that we can quickly swap different versions for tests and photographs
In this photo it is very clear that the CDTU option puts all small parts on the bottom of the PCB (they are on top, but everything is inverted---the tubes are actually on the bottom).	This is another view of a CDTU build. The decision to build as CDTU or CUTU can be made at the time that the kit is being built. Only the sockets, some dozen jumpers and less than 10 components require special attention.	This is the new clock display, with seconds shown as a 15-second-step progress bar. All segments are off for second zero, then one segment is added for each 15 seconds of the minute---finally something useful to do with those underline segments.	This is a great case by Claus Urbach in Germany. It happens to be for the 2002 model, but you wouldn't know that if I hadn't said so.
This is our unique leather case version (not sold as a kit). It is designed in the tradition of fine handbags, camera cases, instrument cases, etc. This case is designed by Raymond Weisling.	Here is a view showing the leather booties for the tubes. Even covered tightly with leather, the tubes still never get more than slightly warm.	Sture Nystrom of Lulea, Sweden used Telefunken ZM1350 Varisymbol planar tubes to make this thin wall-mount FLW. No circuit changes were necessary. The ZM1350 work perfectky.	Here we can see how Sture took the taller cpmponents and laid them on their side, to get a thinner profile. The ZM1350 do not mount on the FLW PCB, but require a separate board, in this realisation connected by wires.
Joe Morse put the FLW on a clamp stand usually used for building or servicing PCBs. This is a no-case option.	Mike Wiese made a very attractive wooden case, using the CDTU mounting option. The unit was so proud that it promptly displayed NIXY just as the camera was poised.	The same case (by Mike Wiese) as seen from the rear corner. The components are on the bottom to allow the full tube to project upwards.	Here the case by Mike Wiese is shown cantelevered off the wall. Not as thin as the ZM1350 above, but still it is a very elegant case.
MORE COMING SOON	Builders, send us your photos

Rear view of unit. Note the transformer mounting between and just behind nixie tubes, and on spacers above the diode matrices.	Detail of lower PCB. This has a power supply, 7490 counters, 7474 latches and three different clocks. The potentiometer on left is for display speed.	Top PCB contained 74141 nixie drivers and 153 diodes to decode the segments for the ten letters of each position.
Detail of diodes alongside the driver chips. It looks like these are actually 7441 chips. Some were produced with 7441 and other with 74141 chips.	Here is the 1973 version up and running. Not bad after about nine times being moved from house to house, city to city, and country to country. (Yes, it was a drag.)	This is a block diagram of the 1973 version showing how it worked without any micro-controller or memory. The only memory was 153 character-forming diodes.