[Coco] Cross Post from the Facebook Page about the RGB2VGA Board

Gene Heskett gheskett at wdtv.com
Sat Jul 11 00:11:31 EDT 2015


On Friday 10 July 2015 23:56:30 Zippster wrote:
> My favorite is AIM brand 3.3% RA cored (fully activated) .032” 63/37
> solder. It flows better than anything else I’ve tried.  I use it for
> everything including SMT.
>
> I get it from this seller on eBay in 1lb spools.  ~$20 delivered
>
> <http://www.ebay.com/itm/251485477311
> <http://www.ebay.com/itm/251485477311>>
>
> - Ed

I use a silver bearing solder, much stronger than the usual eutectic 
63/37 alloy.  Typical silver content is 2 to 4% but the 4% does cost a 
bit more. The silver only raises the melting point maybe 30F.  But the 
tensile strength is 3-6x higher.
>
> > On Jul 10, 2015, at 10:31 PM, John B <trymyz at gmail.com> wrote:
> >
> > That makes sense.  I am on a much smaller scale.  LOL  Where do you
> > get your solder from?  Could you send me a link to what you use?
> >
> > On Fri, Jul 10, 2015 at 11:27 PM, Zippster <zippster278 at gmail.com> 
wrote:
> >> If you were applying it a little at a time I guess I could see
> >> that, but submerging boards in an inch or two of iso works
> >> perfectly for me. I do go through a lot, but it’s cheap.
> >>
> >> I use a high rosin flux leaded solder (3.3% flux) as well as plenty
> >> of Amtech 4300 (syringes) when called for, so the boards are well
> >> fluxed when finished.  :)
> >>
> >> I’m doing tens or dozens of boards at a time, so a plastic bin and
> >> a serious bath is my method.
> >>
> >> - Ed
> >>
> >>> On Jul 10, 2015, at 10:11 PM, John B <trymyz at gmail.com> wrote:
> >>>
> >>> Ed,
> >>>
> >>> I have some flux and electronics cleaner I use.  Alcohol works
> >>> good but takes way to much to clean rosin flux.  Even my flux
> >>> cleaner takes some effort.  Its the cheap stuff from the local
> >>> electronics store.  I should probably invest in the more expensive
> >>> flux cleaner.
> >>>
> >>> On Fri, Jul 10, 2015 at 11:05 PM, Zippster <zippster278 at gmail.com>
> >>
> >> wrote:
> >>>> I’m following this thread with interest, as I’m going to be
> >>>> finishing up theRGB2VGA boards that people had ordered from Kip
> >>>> to get that project successfully completed.
> >>>>
> >>>> It is true that different monitors are more or less tolerant to
> >>>> certain differences in signals, that could explain
> >>>> some of what is being seen here.
> >>>>
> >>>> Regarding cleaning boards, 91% isopropyl alcohol works
> >>>> wonderfully.
> >>
> >> What
> >>
> >>>> I do is submerge the boards in the iso in a small
> >>>> tupperware type container, soak for 10 minutes or so, brush them
> >>>> with a toothbrush while in the bath, then rinse with fresh iso
> >>>> and air dry. Be sure to use the 91%, the lower concentrations
> >>>> have too much water in them.  It’s available at drug stores,
> >>>> walmart, etc.
> >>>>
> >>>> - Ed
> >>>>
> >>>>> On Jul 10, 2015, at 9:39 PM, Steve Batson
> >>>>> <steve at batsonphotography.com
> >>>>
> >>>> wrote:
> >>>>> John,
> >>>>>
> >>>>> Have you changed the resistors yet, or are you using the
> >>>>> resistors
> >>>>
> >>>> recommended for the design? I was seeing jitter, where the entire
> >>>> screen would jerk and occasional waves going through it mostly
> >>>> noticeable on
> >>
> >> the
> >>
> >>>> edges. Also, it didn't seem consistent, sometimes it was worse
> >>>> than
> >>
> >> others.
> >>
> >>>> Based on what Roger had found, it sounded like there were a
> >>>> number of issues being caused by the original resistor values.
> >>>> Voltage Levels were not what they should be. Also there was
> >>>> issues with the HSYNC and VSYNC again caused by original resistor
> >>>> values. Luis and posted on the FB
> >>
> >> page a
> >>
> >>>> response to one of my questions that some CoCo's are noisier than
> >>>> others and this may very well be true, but I'd guess symptoms
> >>>> could be worse on some systems then others which could be the
> >>>> combination of the CoCo and Monitor. From discussions with Roger
> >>>> about this and how he fixed it, I'm going to go out on a limb
> >>>> here and suggest that with his suggested
> >>
> >> resistor
> >>
> >>>> values, the video will most likely be crisp, clean and jitter
> >>>> free on
> >>
> >> most
> >>
> >>>> any CoCo and VGA monitor unless they have problems of their own.
> >>>>
> >>>>> It was a bit of a pain in the butt pulling a bunch of resistors
> >>>>> out and
> >>>>
> >>>> replacing them with Rogers suggested values, but I'd highly
> >>>> recommend
> >>
> >> it if
> >>
> >>>> you haven't done so already. It was totally worth it! If you have
> >>
> >> already
> >>
> >>>> replaced the resistors with the new values and are still having
> >>>> issues,
> >>
> >> I'd
> >>
> >>>> suggest the following:
> >>>>> 1) Inspect your board and make sure you have no possible shorts.
> >>>>> Clean
> >>>>
> >>>> it real good with alcohol or other good electronic board cleaner
> >>>> and thoroughly dry.
> >>>>
> >>>>> 2) Check all the cables including power going to the board and
> >>>>> make
> >>
> >> sure
> >>
> >>>> all is well
> >>>>
> >>>>> 3) Make sure the ribbon cable isn't right next to a transformer
> >>>>
> >>>> including the CoCo power power supply (thought I am not having
> >>>> issues
> >>
> >> even
> >>
> >>>> if set the board right on top of the CoCo above the transformer).
> >>>> This probably is NOT an issue.
> >>>>
> >>>>> 4) Remove wire I mentioned that was a ground fix.
> >>>>>
> >>>>> Anyway, let me know if you have changed the resistors yet or
> >>>>> not. I'm
> >>>>
> >>>> very curious to see where you are at.
> >>>>
> >>>>
> >>>>
> >>>>
> >>>> --
> >>>> Coco mailing list
> >>>> Coco at maltedmedia.com
> >>>> https://pairlist5.pair.net/mailman/listinfo/coco
> >>>
> >>> --
> >>> Coco mailing list
> >>> Coco at maltedmedia.com
> >>> https://pairlist5.pair.net/mailman/listinfo/coco
> >>
> >> --
> >> Coco mailing list
> >> Coco at maltedmedia.com
> >> https://pairlist5.pair.net/mailman/listinfo/coco
> >
> > --
> > Coco mailing list
> > Coco at maltedmedia.com
> > https://pairlist5.pair.net/mailman/listinfo/coco

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>


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