I have a magnavox 32mf231d with a couple of caps that just failed, lucky me. The pair that were on the power supply board were 1200uf, 35v. I went to radio shack looking for the exact thing, and they did not have them. They did have 2200uf, 50v caps and I was told that these would be fine to use as because they held more capacity. I remove the broken caps, install the new caps and put everything back together. When I plug my screen in, there is a beeping/warning sound coming from the power supply board and the tv won't turn on. Any thoughts on what is now the problem? Is it that the caps are so far above the originals?
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Replaced bad caps, still having problems
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Re: Replaced bad caps, still having problems
You need low ESR caps [which rack-shack does not carry] and whoever told you 1200uF -> 2200uF was okay was a moron.
Those caps are used to remove [filter] Ripple from the power supply.
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The uF is chosen based on the expected Ripple frequency and the value of the inductor in the filter.
Changing uF that far 'de-tunes' it from being optimized for that frequency.
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GP caps [like places like rack-shack sell] have a higher ESR which [without getting too deep] means they have a higher resistance to Ripple and thus the Ripple tends to stay in the power circuits. IC chips don't work real well when voltage sent to them is jumping all over the place.
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I hope you saved the old caps.
Needed to get the ESR and Ripple specs to find correct replacements.
.Mann-Made Global Warming.
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Re: Replaced bad caps, still having problems
Radioshack has been worthless for most things since I was in High School.
I Graduated in the 70's.
.Mann-Made Global Warming.
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Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
- Dr Seuss
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You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
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Re: Replaced bad caps, still having problems
Pcbonez you have it backwards, he had 1200 if and ratshack sold him 2200uf caps.
But everything else bonez said is right. Between the higher esr and higher capacity it probably detuned the circuit so bad it wont cycle properly. Post the brand and series of the caps and we can steer you in the right direction.
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Re: Replaced bad caps, still having problems
Originally posted by inuyasha.rules View PostPcbonez you have it backwards, he had 1200 if and ratshack sold him 2200uf caps.
But everything else bonez said is right. Between the higher esr and higher capacity it probably detuned the circuit so bad it wont cycle properly. Post the brand and series of the caps and we can steer you in the right direction.
The caps I had before were from CapXon. 1200uf, 35v.
Are these from MCM going to fit the bill?
http://www.mcmelectronics.com/produc...LAID=220394416
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Re: Replaced bad caps, still having problems
Dont know if this helps any but here are a couple of threads with this set.
https://www.badcaps.net/forum/showthread.php?t=13566
https://www.badcaps.net/forum/showthread.php?t=13832
After your experience with that Radio Shak, I want to drive up there and fire the guy myself. I dont work for them but I'll tell the guy to punch out and go home!
These (badcaps) guys are correct in telling you about this error.The strong-minded rise to the challenge of their goals,the weak-minded BECOME HATERS
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Re: Replaced bad caps, still having problems
Originally posted by flavious27 View PostThe caps I had before were from CapXon. 1200uf, 35v.
Are these from MCM going to fit the bill?
http://www.mcmelectronics.com/produc...LAID=220394416
Digikey has Panasonic FC for $1.25 or Panasonic FR for 1.18. Shipping from digikey is around $2.50 USD and arrives in 48 hours.
The choice between FC an FR will depend on what original Capxon series you have. On the Capxon cap should be a two letter code as per this post
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Re: Replaced bad caps, still having problems
Originally posted by inuyasha.rules View PostPcbonez you have it backwards, he had 1200 if and ratshack sold him 2200uf caps.
But everything else bonez said is right. Between the higher esr and higher capacity it probably detuned the circuit so bad it wont cycle properly. Post the brand and series of the caps and we can steer you in the right direction.
""1200uF -> 2200uF""
I didn't get anything backwards.
.Mann-Made Global Warming.
- We should be more concerned about the Intellectual Climate.
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Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
- Dr Seuss
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You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
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Re: Replaced bad caps, still having problems
Originally posted by retiredcaps View PostWow, $3.83 for one no-name cap.
Digikey has Panasonic FC for $1.25 or Panasonic FR for 1.18. Shipping from digikey is around $2.50 USD and arrives in 48 hours.
The choice between FC an FR will depend on what original Capxon series you have. On the Capxon cap should be a two letter code as per this post
https://www.badcaps.net/forum/showpo...39&postcount=2
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Re: Replaced bad caps, still having problems
Here is the datasheet.
Ripple is obvious.
The ESR is for all intents and purposes is Impedance. [At 100kHz which is what they show.]
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You want caps with the same or more Ripple.
And, the same or less ESR.
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If your exact cap isn't in there it is special order.
In that case use the specs for the closest one [by uF/volts] with the same size can.
.Last edited by PCBONEZ; 06-12-2011, 07:04 PM.Mann-Made Global Warming.
- We should be more concerned about the Intellectual Climate.
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Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
- Dr Seuss
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You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
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Re: Replaced bad caps, still having problems
Originally posted by PCBONEZ View PostHere is the datasheet.
Ripple is obvious.
The ESR is for all intents and purposes is Impedance. [At 100kHz which is what they show.]
.
You want caps with the same or more Ripple.
And, the same or less ESR.
.
If your exact cap isn't in there it is special order.
In that case use the specs for the closest one [by uF/volts] with the same size can.
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So would something like this be okay:
http://search.digikey.com/scripts/Dk...name=P12406-ND
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Re: Replaced bad caps, still having problems
What size is the can on the old ones?
.Mann-Made Global Warming.
- We should be more concerned about the Intellectual Climate.
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Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
- Dr Seuss
-
You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
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Re: Replaced bad caps, still having problems
Well, if I had a stick of chap stick....
The diameter is important.
.Mann-Made Global Warming.
- We should be more concerned about the Intellectual Climate.
-
Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
- Dr Seuss
-
You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
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Re: Replaced bad caps, still having problems
That's way off.
Let me know when you get a ruler or a tape measure.
.Mann-Made Global Warming.
- We should be more concerned about the Intellectual Climate.
-
Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
- Dr Seuss
-
You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
-
Comment
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Re: Replaced bad caps, still having problems
Let me know when you get a ruler or a tape measure.Mann-Made Global Warming.
- We should be more concerned about the Intellectual Climate.
-
Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
- Dr Seuss
-
You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
-
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