Just checking - recap only electrolytics?

proto

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Looking to recap my chassis. It has many types of caps… i see how cap kits only seem to have electrolytic caps. So i assume only electrolytic caps tend to need replacing?
 
Looking to recap my chassis. It has many types of caps… i see how cap kits only seem to have electrolytic caps. So i assume only electrolytic caps tend to need replacing?

What makes you think any of them need replacing?
 
Electrolytic cap's have a "use by date"
typically only have a 15yr shelf life,
typically only have a rated working life of 2000 hours to 4000 hours,
then being in monitor chassis they will heat stress, shorten the life.
 
Many feel they should be replaced.

Vendors of these products and those who profit from doing cap kits are especially vocal and successful about getting people to buy their products and services.

Nearly all of my games are running their original caps, and they look great. People have literally been telling me for decades I need to cap my games. Some of these people have re-capped their same games more than once in this period.

In the rare case where I have a monitor issue, the solution has not been the caps, but reflowing or adjusting.

I often see reports of people breaking perfectly working monitors trying to cap them for no reason. I find this odd.

Others disagree.

It's your game, do what makes you happy!
 
Honestly, I only perform a capkit if the monitor has color or functional issues. Otherwise, I leave it alone.
And yes, a capkit does make a big difference in the quality of the picture (colors, sync, voltage regulation, etc). :cool:

So there are two points of view, I guess ->

1. If it ain't broke, don't fix it.
2. Preventive maintenance (even if nothing is obviously wrong).

Electrolyics have a dielectric that degenerates over time. This incurs lower capacitance and increased ESR.
Both of which will affect the circuit performance.

Keep in mind, also, that it is argued that capacitors made many years ago can still be functional and within spec as the quality was better BITD.
Testing (out of circuit) is the best way to know if a cap is still in spec. Capacitance is frequency dependent, so a good ESR/Capacitance meter with variable frequency options should be used.

Other types of caps, mylar/ceramic etc, do not have the same dependencies on time/temperature/voltage-affects/ripple etc.
However, any cap can degrade if abused. Visual inspection is not always a definitive way of determining if a cap is bad or not.

Due to the local heating affects in a monitor or power supply, electrolytics on these boards are typically more scrutinized than others (i.e. those on a logic PCB).

🍆 YMMV
 
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Honestly, I only perform a capkit if the monitor has color or functional issues. Otherwise, I leave it alone.
And yes, a capkit does make a big difference in the quality of the picture (colors, sync, voltage regulation, etc). :cool:

So there are two points of view, I guess ->

1. If it ain't broke, don't fix it.
2. Preventive maintenance (even if nothing is obviously wrong).

Electrolyics have a dielectric that degenerates over time. This incurs lower capacitance and increased ESR.
Both of which will affect the circuit performance.

Keep in mind, also, that it is argued that capacitors made many years ago can still be functional and within spec as the quality was better BITD.
Testing (out of circuit) is the best way to know if a cap is still in spec. Capacitance is frequency dependent, so a good ESR/Capacitance meter with variable frequency options should be used.

Other types of caps, mylar/ceramic etc, do not have the same dependencies on time/temperature/voltage-affects/ripple etc.
However, any cap can degrade if abused. Visual inspection is not always a definitive way of determining if a cap is bad or not.

Due to the local heating affects in a monitor or power supply, electrolytics on these boards are typically more scrutinized than others (i.e. those on a logic PCB).

🍆 YMMV
there's instances where leaving the old caps can be bad. one that sticks out is C511 on G07s, that's the B+ filter cap, the HOT can die, which blows F901, which can be a debacle for the inexperienced. on a raster monitor it's usually a 47 uf/160V cap, K7000s burned them out a lot and that will result in the monitor either not turning on or being intermittent. so if your monitor only kind of maybe works sometimes, that's a good time to cap it. lol
 
Great! Thanks for the discussion. Disnt realise there's a debate about whether its a good idea to do it or not.
 
Great! Thanks for the discussion. Didn't realise there's a debate about whether its a good idea to do it or not.

with our machines being over 35yrs old,
some cap's will do the time,
but it can come down to the heat/environment the hours they have done,
 
Great! Thanks for the discussion. Disnt realise there's a debate about whether its a good idea to do it or not.
I always say treat your games like they're classic cars. I follow a guy named Car Wizard YouTube and he talks about people buying cars 25+ years old at auctions and how the seals on them will fail and it will just become a greater issue later.

if you're inexperienced at soldering, caps are very easy to manage. if you follow what I recommend and solder the important headers pins and parts that where the solder gets heat damaged and breaks down from the current that's flowed through them for 30+ years, you'll gain more soldering experience. and your monitors will work better.

if they were intended to be maintenance free then people like me would be out of work
 
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