shielding played an important part
 

In many of the early color sets (as well as b & w) for that matter, it was imperative to replace any shielding removed for any service operation.

Failure to replace shielding after service could cause a miriad of problems.

Even something as simple as a broken ground connection of the rf cable between the rf output and the if section could cause very weird problems if one wasn't aware of the result of such failures.

Make sure when you are restoring your oldies that care is taken to replace tube shields as well as shields around sensitive areas.

My number one rule of serving was, if the engineers put it there, it must be there for a reason!

Happy restorations.

It seems that many TV servicemen did not follow this rule. I have seen many a set with the the shield on the tuner missing!!!. I am sure a lot of their customers had sets that did not perform as well as they could have because of this.

(other items that are often missing are the screws to hold the back on).

I've often spoiled the lovely brown patina of a tuner shield when someone else's chassis was on the bench. Ever wonder how the 10-20 years of accumulation got there? Two smokers :smoke: :beatnik: dust, dog dander, and lest we forget pan-fried meat most mornings and evenings!

What was most annoying was the little grease-impregnated sponge inside Magnavox shields. The sponge would disintegrate over time, and the tuner would need a massive hosedown with Blue Shower to get the stuff out!

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dishwasher is a good idea. i take a lot of projection chassis to the car wash that has been infested with rodents or bugs. water will not hurt anything as long as it had dried out before power is applied. steve

Workinh in HVAC is to my advantage, as I have sheet metal readily available. I can make new shields as needed.

what is that little sponge for?

I've always heard about servicemen washing a really smoky chassis in soap and hot water, but have never really wanted to try it, for fear of destroying pure unobtanium. Does it really work?

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I have not personally encountered the Magnavox tuner sponge but this sounds like a tuner cleaning gimmick that was meant to be installed inside the tuner shield and impregnated with tuner cleaner so it could "automatically" clean the contacts....seems like it was a Chemtronics product.