Restringing the dial cord for non-digital Ten-Tec transceivers.....
I recently restrung the dial cords for my Century 22 and Argosy
(non-digital) transceivers (same exact physical layout). It isn't a
particularly difficult procedure other than getting the main cord's
length right and tying a couple smallish knots (thought it would have
been nice had I learned to make fishing flyies!).
Preparation: Get the restring kit from Ten-Tec. It is only a couple of
dollars and includes sufficient lengths of the main cord and the flex
cord to redo at least two transceivers. It doesn't come with instructions.
The main cord is the longest cord and is non-stretchable.
1. Remove all front panel knobs (two different allen wrenches are
needed). You may want to place them on the desk in the pattern that they
were removed to make re-assembly easier due to different set screw
positions.
2. Set aside the two felt washers that were under the main tuning knob.
You will use them on the re-assembly.
3. Carefully pull off the calibrated main tuning dial skirt. It is snug
but pressure fit.
Note: There is a 'D' shaped wire clip on the back side of the calibrated
skirt. This is what actually holds the skirt on the shaft. Do not loose
it. You will use a strong piece of thread, or old dial cord, in a loop
around the open flat tip of this clip to temporarily open the clip a bit
during the re-assembly. One the skirt is back in place you can release
one end of that thread and it will pull free. This is a tricky process
that may take you a few attempts to accomplish but as long as you don't
loose that clip or forget how to re-insert it into the sleeve you will
do ok. Also, many of the Ten-Tec manuals include an illustration showing
a different procedure to replace the dial skirt using a flat piece of
metal. Either process works, but the dial cord is readily at hand.
4. Remove the four corner screws that are now holding the front panel in
place. (Remember to not over tighten these upon re-assembly or you will
crack the panel.).
5. See the Note below and then carefully pull the front panel forward
until it is fully released. Set aside the front panel.
Note: There is a small LED glued into the ALC panel hole. The long leads
of this LED go into a floating two wire jack that protrudes through a
small hole in the under metal front panel. These wires are all that is
actually holding the panel in place at the moment. There is not problem
removing the panel. You simply must remember to pull that jack out of
the hole a bit during the re-assembly and make sure the LED wires are
inserting themselves properly before pushing the panel back in place.
Otherwise no LED indicator! I can't see you accidentally flipping the
jack over as there really isn't enough room for that to happen so wire
polarity shouldn't be an issue.
6. Turn the main PTO fully counter-clockwise.
7. If the old cord assembly is physically intact just too stretched to
work make a drawing of their path beforehand. Carefully remove the old
dial cords There are two bent clips on either end of the stretched
cord. You may want to salvage them although the Ten-Tec kit includes one
set.
8. There is a black plastic cam center bottom of the front panel. Push
this fully counter-clockwise which is the position it must be in when
you make the final length of the long cord.
9. Note the sliding pointer assembly itself. There are two tie points on
this sliding pointer. Take one end of the new main cord and tie it
tightly (use a good knot here) around the right tie point. Carefully cut
off the excess piece of cord close to the knot.
Note: The tie point on the right has double duty as both a tie point and
rigid pulley of sorts. You will probably move this back and forth during
the cord tying process... BUT IT IS INCREDIBLY IMPORTANT THAT THIS
SLIDER BE ALL THE WAY TO THE LEFT once the main cord is tied into place.
This positioning sets the proper left to right travel for the pointer.
10. (Read this carefully, especially if you did not have an old cord to
make a drawing of) There is a shinny fixed pulley immediately to the
right of the rectangular dial window. Run the long dial cord over the
top of this pin and then back to the right tie point of the pointer
slider. You route the cord clockwise around this tie point and then back
to the right all the way across the inner front panel to a movable
pulley. Run the cord in a clockwise direction over that pulley and then
downward diagonally towards the black cam.
There is a small fixed pulley point on the right corder of the cam and a
much larger fixed pulley point at the axis of the cam. This larger point
does not have a flange but don't worry as the front panel keeps the cord
from coming off this larger fixed pulley point.
Route the cord clockwise one half turn around the bottom surface of the
cam's smaller pulley point on the cam and then one-half turn
counter-clockwise over the top surface of the larger cam pulley point.
Continue the path of the cord towards the inner, larger, shaft portion
of the PTO shaft assembly.
11. Wrap the cord one and a half turns in a clock-wise direction around
the PTO inner shaft assembly. Note the small pin extending outward from
this shaft. You will tie off the long cord at this small pin. Read the
following Note first.
Note. Before tying off the long cord on this PTO shaft pin make sure:
_ The sliding pointer is all the way to the left.
_ The long cord is routed correctly from the sliding pointer to the
small shinny fixed pulley, back around the right-most pin on the sliding
pulley, back and over the large pulley on the top right of the front
panel, down diagonally to and around the two points on the cam, and then
one and a half turns clockwise around the inner PTO shaft itself.
_ The final length of the cord must be just long enough to allow the
sliding pointer to just make it fully to the left with the PTO fully
counter-clockwise. If the cord is short then the pointer will not travel
far enough and your dial calibrations will be high. If the cord is too
long then there will be slack with the pointer all the way to the left
and the PTO fully counter-clockwise and the cord will come off one of
its pulley points (not good). You may have to experiment with this
procedure a few times till you get the length right.
12. Tie off the long cord on the PTO shaft pin (once again refer to the
above note). Make a good, small knot and cut off the unused portion.
13. Wrap a free end of the elastic cord tightly around the left-most pin
on the sliding pointer. Use a small piece of aluminum as a wrap to
snuggly squeeze the elastic cord around that pin so it won't come off
easily.
14. Route the elastic cord downward diagonally to the left around the
two pulleys on that end of the front panel assembly. You are just going
over the pulleys and 1/8 of a turn and not around them.
15. Continue routing the elastic cord to the right towards the PTO
shaft. Originally the end of the old elastic cord terminated at the left
PTO mounting screw immediately to the left of the PTO shaft itself. If
you haven't already removed that screw that had a looped small solder
lug on it, do so now and straighten out that solder lug to reuse or use
the new one Ten-Tec provided.
It the next step you are going to terminate the flexible cord at this
screw/solder lug location. The length of the flexible cord much be just
short enough to apply adequate return pressure on the cord assembly to
pull the sliding pointer fully to the left with the PTO fully
counter-clockwise. Too little cord return pressure and the pointer won't
come fully to the left. Too much pressure and there may not be enough
elastic cord length to allow the dial to go fully to the right with the
PTO cranked fully clockwise. The elastic cord length isn't terribly
critical as long as you get proper pointer travel. Remember this elastic
cord will stretch over time and if you have it tighter than really
necessary it will stretch sooner.
16. Set the length of the elastic cord following the directions just
mentioned.. Use the tab end of a small solder lug as a tie around the
cord itself. Snuggly wrap the free lug end several times around the cord
at the termination point. Cut off the excess elastic cord end. Use the
small screw to mount the terminated elastic cord length on the left PTO
mounting point.
Check your work.
17. Replace the plastic front panel. Make sure the ALC LED leads are
inserting into the floating jack extending from the inner front panel.
18. Once the front panel is fully into position secure it there with the
four corner phillips screws. DO NOT OVER TIGHTEN THESE SCREWS.
19. Replace the main tuning calibrated dial skirt on the inner, larger
PTO shaft. Recall the information regarding this procedure. Use a piece
of dial cord of strong thread to temporarily open the 'D' clamp around
the inner shaft of the dial skirt. Holding the dial skirt firmly in one
hand so it doesn't rotate, apply pressure on that string to keep that
'D' wire clamp slightly open while pushing the skirt onto the PTO shaft.
Once fully into position (about 1/16 of an inch or so from the panel
itself) you can release the pressure on the string and slip it out by
pulling on one and.
20. Replace the two felt washers on the PTO shaft.
21. Replace the main tuning knob. It should compress the felt washers
somewhat.
22. Replace the remaining knobs. Don't get too close to the front panel
otherwise rotating the knobs will scratch or rub the panel finish.
At this point you should have a working dial pointer assembly. The
kurrled edge of the pointer cam can be felt just inside the lower center
bottom of the front of the transceiver. Moving this cam will allow a
degree of string calibration. It may be necessary to move this cam
slightly in the future as the elastic cord ages and stretches somewhat.
___________________________
These instructions work for the Century 22 and the Argosy's and probably
on all the earlier non-digital Argonaut, Triton, Delta, and Omni
transceivers.
Hope this is useful.
73,
Jerry, KG6TT
Fairfield, CA
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