View Full Version : Singer TV6U-Curious why these colored markings


AiboPet
07-15-2013, 09:50 PM
I am recapping another of my little Singer TV6U "sweeps" boards....just to see if a casual "complete" recapping will yield better results than the other "one-by-one" board I did a few days ago.

I noticed that ALMOST all the electrolytics have been marked on top either red...or green. ALL the same board have these markings. They are completely filled in on top of the cap in like red or green "Sharpie" style marker. There are only a couple on this board that are just left silver on top.

Without looking where EACH one of these are in the Sams (in the schematics) and guessing if these colors mean anything, is there some sort of code to this??

Is this some way of saying "vertical" or "horizontal" sections?

I did notice most of the differences in vertical were "green" marked caps, and at least the one smaller cap I changed out that made a big difference in Horiz hold...was marked red. Was this just coincidence?

I don't see anything in the SAMS that mentions the "marker" colors on top of the electrolytics. Some of the green mylars are also marked red on top as well...but in a touch of red paint.

I'm hoping to save some grief if these may be horizontal and vertical identifications. I figure if I changed all the green marked ones at once, that maybe I could concentrate on the linearity/size issues....BEFORE tackling a horizontal issue? If there IS some rhyme or reason to this, I guess it would be wise to mark the replacement caps with a red or green Sharpie on top as well?

ChrisW6ATV
07-16-2013, 10:17 PM
I have not noticed that kind of marks in any equipment I have worked on. Japanese equipment of that era is very poorly labeled inside, so I doubt that the marks are any type of code related to the circuit functions.

In later years, as you probably know, parts were often numbered in groups by their functions (Sony vertical circuit parts are in the 500s, etc.).

Electronic M
07-17-2013, 01:49 AM
Perhaps somebody was getting ready to recap it before marking the good ones green and the ones that tested bad in red...

AiboPet
07-17-2013, 08:06 AM
Nope....all three sets have these same markings, and the caps I replaced in the (now working) set...were mostly marked green. Someone in the factory marks them these two colors for some odd reason. I could painstakingly look where each one is in the schematics, but that would take longer than just pulling them out and replacing 'em.

Almost EVERY electrolytic in these sets I have checked are either WAY off....or completely open. Each one makes some difference or other in vertical height or linearity. I still haven't gotten to the one causing whatever linearity weirdness I'm still seeing in the one set. Figured I will get one of the other sweep boards completely recapped and switch it in. Most the caps I have in my big plastic "bin-O-caps" are not the exact values. I don't have 50uf caps in that collection at all....so I go with 47uf and they seem to be doing alright. Most of my caps are 50v, so they are WELL above the voltages of most of the original 16V caps.