On 1/1/2011 4:56 PM, Joe Roberts wrote:
> At this point, 30 years old, those TT PTO rigs are "the new boatanchors"
> and I am of a mind that it pays to think in terms of restoration...it's
> about that time.
> I have gone through a couple Tritons, Omni Cs, and an Omni V replacing
> all the electrolytic caps with amazing results. I want to restore a
> Corsair in 2011...new year's resolution.
> Use modern low ESR high frequency caps designed for digital or switching
> supplies, 105 C rating and the radio will sport far better parts than
> were available when it was made. This effort will reward you with a
> super low noise, high performing rig.
> Ten Tec used general purpose caps, which weren't the greatest caps in
> history when they were new, and they often used miniaturized series
> which just don't hold up that well. Even if a radio seems to work OK,
> you'll find out what you were missing when the caps are updated. Start
> with power supply, IF/AF, and counter board and decide if it is worth
> going on.
As did most makers, just on price. But I've bought NEW miniature GP
electrolytics that didn't pass my power factor test fresh out of the
sack. Electrolytics don't age gracefully when not powered, but they do
age slower when used. The nasty thing about poor caps is that each one
degrades the equipment a little, not enough to find it by signal
tracing, but enough that when a whole bunch are replaced the equipment
works much better.
> I ran afoul of "it it ain't broke, don't fix it" with an FT-102 rebuild.
> It seems Kenwood 830s and contemporary Yaesus are getting fragile these
> days, but the superior materials and simple, logical layout in 1980s Ten
> Tec provide a better base for reworking. These radios are extremely
> comfortable to work on, with high grade boards and well spaced out parts.
Same miniature electrolytic caps aging problem.
And its good to clean the contact surfaces where grounds meet the
chassis through PC board mounting screws. Maybe even to add shake proof
lock washers to get a better bite, but the plastic will relieve pressure
over time so they will need periodic tightening just like they always have.
> For alignment, a frequency counter is a necessity for getting all the
> oscillators right.
> Get a little bottle of Deoxit and clean all connectors as you go.
> Joe N5KAT
73, Jerry, K0CQ
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