Cap Talk.... - Videokarma.org TV - Video

Tubejunke · #1 12-19-2003, 01:01 AM

Since my 58 Zenith has no vertical sweep with a hum for sound I am going to go ahead and replace most if not all caps. I always suspect the multi section cans for causing a lot of problems. I guess this is really based on the fact that so many functions are performed within one unit. Is it a better idea to knock those out first. I know many will say replace them all but this is not always necessary. I guess I'm asking if the "cans" go bad more frequently than the smaller ones. I have about 7 caps with values like .1, .047, ect. They are white in color and are not covered in wax like others I have dealt with. I feel stupid for not being sure what they are made of. I feel like they are going to be paper. I only saw one "black beauty" and thats a plus. Acouple of orange drops are the only evidence I have found that the TV ever had much use. I'm pretty sure orange drops are post 1958.

Charlie · #2 12-19-2003, 08:26 PM

This is one of those topics that comes up time and time again.

As far as whether or not to change ALL caps, it's just one of those personal preferences. Seems that everyone here at AK has a different idea on this (which is to be expected in a group as large as we are). There are some of us (myself included) that feel changing everything is the best bet. That way, it's likely you won't need to pull the chassis again anytime soon. True, it's not always necessary, but I guess it's like buying an insurance policy.

It's just a judgement call one makes. For instance, the Motorola I just finished still has all of the ceramic tubular caps in it. I changed only the electrolytics in the cans. The tubular caps all checked out like new.

It also makes sense that changing only the lytics could cause old couplers (especially paper/wax & blk beauties) to fail. The fresh new B+ voltages you get by changing weak lytics will likely seek out and destroy any weak couplers.

Your question of whether or not cans fail first... well, it's a coin toss. All depends on how much the set was used and whether or not it had any other problems that could put a strain on them.

kc8adu · #3 12-20-2003, 05:01 AM

if it is a more common set being restored for a customer i replace all waxpaper,black beauty,and micamold caps.
most of the time all lytics too.
a rare set that is mine like a prewar i will try to keep it original or if it has to play restuff the caps.
its a matter of personal preference.
most of my customers dont watch the bottom of the chassis and want it to work when they light it up for visitors.