listing of corrections and recommendations concerning the
construction and operation of the
Rainbow Bridge/Tuner Kit
Recent additions to this list are placed at the bottom.
Last update made: 5/7/97
- [3/7/97] The printed circuit board holes for the
9 terminals for connecting off-board wires are
under-sized. They are a No. 57 hole and should be No. 56,
a couple of mils larger. You can either try to open them
up a little to get the terminals to seat fully, or just
press the terminals in as far as you can and be
satisfied. They really don't need to have their shoulders
flush with the board. They will be fine once soldered in
place. The first 100 or so boards have the small holes.
Later boards will have this corrected.
- [3/7/97] The holes for the toroid tap wires are
a tight fit. While the holes could be enlarged, it is
best to just make sure that the leads are twisted tightly
and cleaned off when tinned so that they will fit into
the existing holes.
- [3/7/97] In figure 7, the "L" networks
are labeled backwards. The top one should say "Z
BELOW 50 OHMS" bottom one should be labeled "Z
ABOVE 50 OHMS."
- [3/7/97] In Figure 8 and on the printed circuit
board, the terminals in the upper right hand corner of
the board are labeled backwards. The top one should be
labeled "GND" and the one right above the
jumper block J1 should be labeled "50 OHMS."
This error also appears on Figure 3, the EXTERNAL
COMPONENT WIRING DIAGRAM. If you wire per the board
markings, your coax center conductor and ground will be
reversed, causing strange results! This error will be
corrected after the first build of Rainbows (orders above
- [3/7/97] Disregard part numbers on the
glass-bodied diodes. They were ordered as 1N34 and should
operate as expected. Of course you *do* have to note that
the end with the prominent band is the cathode.
- [3/7/97] The LEDs may be a loose fit in the
Rainbow display SIP socket. If they are too loose, simply
tin the LED leads a little with your soldering iron so
that they are a little "thicker." Just don't
heat them for more than a couple of seconds or the diodes
may be damaged.
- [3/11/97] Hole dimensions noted in item 1 were
corrected to be: "They are No. 57 and should be No.
56." (Item 1 is now correct as it stands.)
- [5/7/97] Here's a parts caution for those who
have purchased Rainbow kits: Please carefully check
precision resistor R9 *BEFORE* you install it on the pc
board. It is the sixth one from the end marking on the
taped strip of resistors and its color code should be:
red-blu-brn-red-brn, corresponding to 56.2K ohms with a 1
% tolerance. Several of you have received resistors of
the wrong value. The *wrong* ones are marked
red-blu-brn-gold-brn so their value is 56.2 ohms. The
components were purchased from a reputable supplier and
although we did spot check them, apparently a few wrong
ones got through. Please be sure to measure your R9 with
an ohmmeter to ensure that it's the right value.
Questions or to Report Problems:
If you have any questions or want to
report problems with the Rainbow, please contact: Joe N2CX,
Last Modified May 15, 1997