TNX Gary, that sounds like what I remember seeing elsewhere.... 73, Al
On Sun January 10 2016 5:51:22 pm Gary J FollettDukes HiFi wrote:
> Replace C27, a 1000 uF 16 volt electrolytic that decouples the counter unit
> 12 volt line from the rest of the radio’s 12 volt lines.
>
> The only part of this radio that has anything digital that can cause a
> steady whine like you describe is the counter, especially since you hear
> the whine with RF gain fully down.
>
> Likely there is switching note from the counter on the 12 volt line.
>
> Gary
>
> > On Jan 10, 2016, at 4:03 PM, Al Gulseth <wb5jnc@centurytel.net> wrote:
> >
> > This is just off the top of my head (can't find anything in a quick web
> > search), but I seem to remember something about aging/deteriorating
> > bypass caps (especially electrolytics) in the display subsystem being a
> > source of noise on the digital Tritons and early Omnis.
> >
> > 73 es GL, Al
> >
> > On Sat January 9 2016 10:36:21 pm Kirk Smith via TenTec wrote:
> >> Hello to all...My 544 Triton seems to have a high pitch whine, at low
> >> volume, with the RF Gain up or down. I've read a review on E-Ham about a
> >> mod that eliminated the noise.....they removed the c5 cap 750pf on the
> >> logic board . Well, my schematic does not show this cap & that there's
> >> no actual cap between pin 17 of the IC to Vcc. I also don't see that cap
> >> on my board. Anyway, I listen at low volume & needless to say, the whine
> >> is beginning to make me whine!! Any ideas before the radio heads back to
> >> TT? One last thing, I tested another 544 next to it, & was quiet....my
> >> ser # is 544-1618, the quiet rig is 544-1355.Thanks, Kirk
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> >
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