Here is a reformated version of the Orion Encoder replacement email.
Please let me know if it has any issues
I just completed replacing all of the mechanical encoders (6) on my Orion 1
and thought I'd share some info.
Only 1 was bad (had dead spots), but I had this bright idea that
I wouldn't replace them all so I wouldn't have to do it again anytime soon.
This did complicate things a bit, but did solve the problem I knew I had with
one,
and made one other work much smoother.
KE5C made a series of photos detailing how to get to the encoder board and
replace an encoder
(http://www.w4ish.net/Manuals/pdf/Orion%20RIT%20Encoder%20Replacement.pdf).
This is a very good starting point. I've listed some details I had to deal with
replacing them all.
One additional thing I ran into: The VFO A and B encoder shafts pass through
a bearing.
The knob screws had been tightened down so tightly, that a 'nick' was left on
the shafts;
large enough to not allow it pass through the bearing. I had to polish this
down to get these encoders out.
Here are the details:
1. The BEST thing would be to order the connector and bare board from Ten-Tec
if they have these items available, and put new encodes on it.
2. Take great care in handling the board that has the gold contacts for the
‘chicklet’ keys.
I consider this a design weakness in the Orion. Not only are such keys
mushy, they are easy to damage.
Tactile switches with hinged buttons would have been so much better.
While they work, it does complicate handling this board when servicing.
I used close knit cotton gloves when handling it and made sure the room was
as dust free as possible.
Also made sure to wash my hands before any handling of this board, before
putting the gloves on.
It’s very easy to cause these things to bounce or not work at all.
Oil on the pads or dust on the rubber contact inside the switch will cause
all kinds of problems.
The smaller section of rubber ‘switches’ will stay on the board pretty
easily, but not the section around the LCD opening.
This board and the chicklets were covered after the encoder board was
removed.
3. Don’t waste time trying to preserve an old encoder; clip the pins and if you
have a Dremel
or something similar, cut the mounting brackets on the encoder, then remove
the pins and clips from the board.
Be careful pulling the cut pins out because you can pull a pad off with the
pin, especially on plated through holes;
make sure the solder is well melted. The pins going through the ground plane
are more apt to be a problem,
the others will pretty well fall out when the pad is heated.
4. I do not have a de-soldering station due to the fact that it would be very
expensive for the occasional use I would give it,
so removing the old encoders was very time consuming. A bulb type
de-soldering iron worked fine for the contacts that were not
going through the ground plane, but didn’t do much with those connections
that were.
Solder wick and a 100 watt gun did ok, but I finally had to use the heat and
tap method
(melt the solder and tap the board against something to splatter the solder
out).
The mounting clips required the 100 watt gun and gentle pulling on the
encoder.
Basically getting one side out a little and then the other until it was
free.
100 watts was required, but not something you want to leave on the pad too
long.
5. There is no wiggle room on this board. The tolerances for the mounting holes
are very close.
The holes for the clips have to be as near to solder free as possible to be
able to get the new encoders on.
I trimmed what I couldn’t wick, suck or sling off with an Xacto knife.
Even then, I had to push a small, thin flat head screwdriver into the
mounting holes to make them large enough
to press the encoder mounting clips into. Even after all of this, it took
some very firm pressure to push them in.
6. The new encoders have an indexing tab. This needs to be cut off flush.
I used a polishing wheel on a Dremel to make sure it was smooth.
The metal is soft, so it’s easily cut.
7. The encoder pins are very thin, and I expect, could be damage easily, so be
sure to line them up well
with the corresponding holes and be sure the holes are clean before pushing
the encoders onto the board (when I said firm pressure before, I meant
really firm at times.
Might be easy to break a pin is it isn’t well placed.)
8. Once I had all of the encoders pressed onto the board, before I soldered
anything in place,
I donned the cotton gloves and mounted the encoder board into place (with
the spacers)
and tightened the nylon/plastic (not sure which) ‘nuts’ that hold this board
onto the panel switch board.
Once I had verified that all the encoders turned freely. I soldered one clip
and a couple of pins,
so the encoder would stay in place. I removed the board and soldered
everything well.
Again, the clips required the 100 watt gun (as well as any pins that passed
through the ground plane).
Exercise caution in heating the connection for too long with a 100 watt gun.
9. I clipped any excess from the leads and then used a flux removal pen to
clean up the flux.
This isn’t absolutely necessary, but the less ‘sticky’ stuff on the board,
the better.
Then wiped the board off with a clean lint-free cloth (gently).
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|