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----- Original Message -----
From: pdxareaid
To: TekScopes@...
Sent: Tuesday, September 25, 2012 1:15 AM
Subject: [TekScopes] Re: WooHoo! 465B



hmmm what to use.
my go to is wd-40 but i thought i read something about it not being a good idea.
what do you think of wd-40 for this purpose?
phil

--- In TekScopes@..., "Tom Miller" <tmiller11147@> wrote:
>
> Take the knobs off and put a drop of thin oil on the shaft where it goes into the pot. Give it a day or so and try it. Should help with the noise.
>
>
> Tom
>
>
> ----- Original Message -----
> From: pdxareaid
> To: TekScopes@...
> Sent: Monday, September 24, 2012 11:23 PM
> Subject: [TekScopes] Re: WooHoo! 465B
>
>
>
> yes, i just tried it out. dual rate pot. it felt "grindy" and seemed malfunctioning but with this knowledge i can see it just needs some cleaning maybe, but it is functioning correctly. scratch another fix off the list :-)
> the intensity pot is pretty ugly though it does seem to have gotten a little better since yesterday. i have beat on it pretty hard...i don't think i can avoid cleaning it if i can get into it.
> i'll chase down trigger view in next day or 2 probably.
> thanks for all the help.
> phil
>
> --- In TekScopes@..., larrys@ wrote:
> >
> > It is a dual-rate pot. You turn it just past where you want to be and
> > when you back up it's a slower rate. You can feel it in the amount
> > of torque you have to apply. If you can figure a way to get it in
> > there, Deoxit D5 will help clean it up. Same stuff will also probably
> > help the trigger view switch. A little exercise will certainly help as
> > well.
> >
> > -ls-
> >
> >
> > "pdxareaid" <public_email@> wrote:
> > > thanks,
> > > the wonky pots are hopeless unless there is something i don't
> > > understand about coarse vs fine adjustment but i doubt it.
> > > 1st pass i will try to get them out and deconstruct without breaking
> > > them, if possible. they are still semi-useable with care.
> > >
> > > there is something definitely wrong with trigger view. i was
> > > triggering on calibration square wave and still seeing a flat line.
> > > probably something simple.
> > >
> > >
> > > funny, i have been reading about the tantalum nightmare and considered
> > > myself lucky there were none in the 465M that needed a major PS
> > > rebuild...but here i am with tants in the 465B...lucky it made its
> > > presence knows with smoke and moaning and goo. :-)
> > >
> > > phil
> > >
> > >
> > >
> > > --- In TekScopes@..., "Dave B" <dave@> wrote:
> > > >
> > > > On 25 Sep 2012 at 0:52, TekScopes@... wrote:
> > > >
> > > > > Posted by: "pdxareaid"
> > > > > Date: Mon Sep 24, 2012 5:48 pm ((PDT))
> > > > >
> > > > > i'm not sure of the best way to post this followup for all
> > > previous
> > > > > responders see. so, i'm replying to my original post...
> > > > >
> > > > > i spent some quality time with the new toy today. i guess it just
> > > > > needed some attention...
> > > > >
> > > > > i turned it on and found i was getting one spot on the screen
> > > rather
> > > > > than a massive glow (i kept it de-focused as it was full
> > > intensity.) i
> > > > > looked around at the tantalums that had one smoking yesterday and
> > > > > noticed a solder bead on one of the three. i poked it and it fell
> > > > > off...and a trace slowly snapped back. some adjustments and
> > > things
> > > > > were sweeping! how the heck does a solder bead on the outside of
> > > a
> > > > > tantalum cause this? was there a cold solder i tweaked at the
> > > same
> > > > > time?
> > > > >
> > > > > so since it appeared it was not going to catch fire this time, i
> > > let
> > > > > it run and things stayed nice and stable. i turned it off and
> > > tested
> > > > > all of the transistors in the area of the smoking tantalum (this
> > > is at
> > > > > rear of sweep logic board btw). they all appear ok.
> > > > >
> > > > > man, you people with socketed transistors have it easy. try
> > > testing a
> > > > > transistor on a 465M. you have to desolder it...no sockets!
> > > (except
> > > > > about four i found that probably should not have been there lol)
> > > no
> > > > > sockets is part of the "ruggedized for the military" modification.
> > > > >
> > > > > so, things are working fine with a few mechanical probs. i found
> > > a
> > > > > loose transistor preventing the x1 light on chnl 1, stuck it back
> > > in
> > > > > and that prob is fixed.
> > > > >
> > > > > the horizontal position pot is wonky. lots of play. i've seen
> > > this
> > > > > before on the 465M. i guess 35yrs of use takes it's toll.
> > > > >
> > > > > the main intensity pot is dirty or toast. i will probably attack
> > > it
> > > > > soon.
> > > > > but careful fiddling and it gets you where you want to be.
> > > > >
> > > > > the B delay pot knob is offset to 0.2 when bottomed out. and it
> > > shows
> > > > > on the trace. i think this was previous owners way of correcting
> > > for
> > > > > improper registration on the trace. likely a simple calibration
> > > tweak
> > > > > will fix it and i'll rezero that pot knob.
> > > > >
> > > > > this is a significant one:
> > > > > the A trig view only shows a flat line but everything is
> > > triggering
> > > > > properly (including B sweep stuff). possibly a loose jumper wire
> > > etc.
> > > > > i'll chase it soon.
> > > > >
> > > > > since it was staying up (for 2 hours now) i took PS readings at
> > > test
> > > > > points.
> > > > >
> > > > > voltage VDC, ripple mV p-p
> > > > >
> > > > > supply voltage spec ripple spec
> > > > > +110 108.2 106.7 to 113.3 16 20
> > > > > +55 54.9 54.62 to 55.39 3 4
> > > > > +15 15.00 14.75 to 15.26 1 2
> > > > > +5 5.01 4.92 to 5.09 1 2
> > > > > -8 -8.01 -7.86 to -8.14 1 2
> > > > >
> > > > > not too shabby. i may take a look at getting +110 closer to 110.
> > > i
> > > > > am still nervous about ps filter caps because my 465M worked for a
> > > few
> > > > > hours then tore itself apart with failed caps and exploding
> > > > > transistors. i'll keep an eye on it for a while. it would be
> > > nice
> > > > > not to have to recap this thing. (i know about reforming but i'd
> > > > > rather recap and be sure)
> > > > >
> > > > > all the other bells and whistles seem to be working x10-mag etc.
> > > and
> > > > > timing and vertical deflection look right on.
> > > > >
> > > > > So, not a very exciting fix but so far i have a nice working 465B
> > > but
> > > > > i'm quite sure why :-o phil
> > > > >
> > > >
> > > >
> > > > Well done!
> > > >
> > > > The Tant's with what looked like a blob of solder, are failed parts.
> > >
> > > > That blob, was molten Tantalum Metal ejected from the part when it
> > > > failed. You got lucky clearing the short by knocking off that
> > > blob.
> > > > Best the part be replaced for a long life from now on.
> > > >
> > > > Not sure about the A-Trig View issue. I presume you had a signal
> > > for it
> > > > to trigger on, and that was selected. But maybe just a dirty
> > > siwitch
> > > > contact, or something related in the vertical logic. For now, it
> > > sounds
> > > > like you've a 99% working instrument, and a massive grin no doubt.
> > > >
> > > > Dirty pots, just "Exersize them" back and forth with the power off,
> > > and
> > > > they will then improve with use. Some can be stripped apart and
> > > > cleaned, but very fiddly to do, and needing care not to damage the
> > > track
> > > > etc, plus finding out what the correct lube to put back in there is,
> > > is
> > > > not easy. I'm guessing silicone grease, but I don't know for sure.
> > > >
> > > > Best Regards.
> > > >
> > > > Dave B.
> > > >
> > >
> > >
> > >
> > >
> > > ------------------------------------
> > >
> > > Yahoo! Groups Links
> > >
> > >
> > >
> >
>