[R-390] Gear Train Removal

[Barry Scott]

Well, I don't quite know how it happened, but I can no longer get all the
cams properly aligned.  As I mentioned, I've removed the VR counter so
that's one point of reference that I no longer have.

I had been rotating the MC change gear one click or two and then back and
no problem; however, I think I lost track of which way I had rotated it and
now I can't get back to where 2.000 would normally be displayed by the
counter.

I'll mention that I've kept the Green Gear in place and, contrary to my
previous comment, that gear does indeed keep the MC and KC gears
synchronized and, given that, I don't know how they're no longer where I
can get them back in sync.

According to the manual, as part of the complete gear teardown and rebuild
(which I still have not decided to do), one is supposed to be able to
rotate the MC gear CW (which I presume is taken to mean "CW as viewed from
the rear"), until it hits a stop point and then, back up to the nearest
notch which should correspond to 0.000.  My presumption is that if I back
off to the 3rd click, that should correspond to 2.XXX and rotating the KC
shaft should eventually get the gears (and cams) in the 2.000 position.

I found that there is something that causes a "stop" at full CW and full
CCW.  I think that stop is happening as a function of the Geneva mechanism
and not the 10-turn stops (which aren't engaged when the RF deck is
removed); however, CW or CCW still won't let me get the gears/cams in their
proper setting and am wondering if I'm now truly "stuck".

Any help is appreciated.

Additionally, to avoid getting the transformers' cores wet, I'm removing
the slug racks and transformers while cleaning the gears and, right off, I
found that one of the slugs (for Z2223) was broken.  I'm sure that didn't
help performance any.  I have it CA glued back together so that should help
when I get this all reassembled.

Thanks again,
Barry - N4BUQ


On Mon, Sep 2, 2024 at 5:55 PM Barry <n4buq at knology.net> wrote:

> While I have the RF Deck out, I'm going to clean and lubricate the gears,
> rollers, etc.  Reading the manual, apparently the from "apron" of the gear
> train can be removed without all that much difficulty.  If I remove that
> apron, do the gears stay with the main part of the deck or does some of
> them come off with the apron?
>
> I'm asking because, while I'm still considering a complete teardown (which
> is just a bit more daunting than the A model which I've done before), it
> might be good enough if I can maximize the exposure of the gears and just
> settle for cleaning/lubing them in situ.  Any comments on that?
>
> Thanks,
> Barry - N4BUQ
> ______________________________________________________________
> R-390 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/r-390
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:R-390 at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>