low ESR cap question & vertical deflection ...
 

"Leon Kiriliuk" wrote in message
...
My old "monitor" has a vertical deflection problem. I've noticed one of
the caps leaked. (the problem was the top 1/2 stretched, while the bottom
shrunk.. until the tube got warm.. but stayed almost the same).

According to the net, it's either Marcom or Elna caps (1uF 50V 105 degrees
electrolytic).

So I went and put in there a 1uF 200V 105 degrees electrolytic. Now the
picture is shrunk to the middle 1/3 of the screen!

These caps are used to drive a AN5521. If I replace the IC, should that
fix my problem? are there any equivalent drop in IC's in case I can't find
it local to me?

Better yet, what are "low-esr" caps, and how can I tell them when
purchasing? Do I have to replace the 2 caps with the exact same "red"
caps, or are the ones I put in there now good enough?


Thanks!



Replacing the IC isn't going to fix it; you still have cap problems.

Mark Z.

Post the model of the set and the locations of the cap and you might get
more specific help.

You likely have other caps that are bad.

Read the specs to find low esr caps. You will not likely find local
suppliers with a range of options in this area. It is not particularly
critical in most cases, but if you increase the voltage rating it may become
so. A 200V cap will generally have a higher esr than a 50V cap, all else
being equal.

Read the manufacturer's specs to find the esr value.

Leonard


"Leon Kiriliuk" wrote in message
...
My old "monitor" has a vertical deflection problem. I've noticed one of
the caps leaked. (the problem was the top 1/2 stretched, while the bottom
shrunk.. until the tube got warm.. but stayed almost the same).

According to the net, it's either Marcom or Elna caps (1uF 50V 105 degrees
electrolytic).

So I went and put in there a 1uF 200V 105 degrees electrolytic. Now the
picture is shrunk to the middle 1/3 of the screen!

These caps are used to drive a AN5521. If I replace the IC, should that
fix my problem? are there any equivalent drop in IC's in case I can't find
it local to me?

Better yet, what are "low-esr" caps, and how can I tell them when
purchasing? Do I have to replace the 2 caps with the exact same "red"
caps, or are the ones I put in there now good enough?


Thanks!

It's a Toshiba CX28400 / chassis tda9005.

I've replaced all the electrolytic caps on the entire board that are bigger
than the smallest ones.
Including all the ones the in the C3XX range.

I don't have a service manual for this chasis, and wanted to fix it.

How can I tell a cap is low ESR when purchasing it?


"Leonard Caillouet" wrote in message
...
Post the model of the set and the locations of the cap and you might get
more specific help.

You likely have other caps that are bad.

Read the specs to find low esr caps. You will not likely find local
suppliers with a range of options in this area. It is not particularly
critical in most cases, but if you increase the voltage rating it may
become so. A 200V cap will generally have a higher esr than a 50V cap,
all else being equal.

Read the manufacturer's specs to find the esr value.

Leonard


"Leon Kiriliuk" wrote in message
...
My old "monitor" has a vertical deflection problem. I've noticed one of
the caps leaked. (the problem was the top 1/2 stretched, while the bottom
shrunk.. until the tube got warm.. but stayed almost the same).

According to the net, it's either Marcom or Elna caps (1uF 50V 105
degrees electrolytic).

So I went and put in there a 1uF 200V 105 degrees electrolytic. Now the
picture is shrunk to the middle 1/3 of the screen!

These caps are used to drive a AN5521. If I replace the IC, should that
fix my problem? are there any equivalent drop in IC's in case I can't
find it local to me?

Better yet, what are "low-esr" caps, and how can I tell them when
purchasing? Do I have to replace the 2 caps with the exact same "red"
caps, or are the ones I put in there now good enough?


Thanks!

You can tell low ESR caps by reading the manufacturer's specs for that
particular series of parts. If it is not listed as a low ESR cap or the ESR
is not specified, assume it is a more typical cap. As I said, it is likely
not an issue until you start increasing the voltage rating on the
replacement.

That model is not one that I have a manual for, but some of the Toshiba sets
had a pot for adjusting the height that would cause problems. I would look
for bad connections, check the voltages at the output IC, and try to adjust
the height.

Leonard

"Leon Kiriliuk" wrote in message
...
It's a Toshiba CX28400 / chassis tda9005.

I've replaced all the electrolytic caps on the entire board that are
bigger than the smallest ones.
Including all the ones the in the C3XX range.

I don't have a service manual for this chasis, and wanted to fix it.

How can I tell a cap is low ESR when purchasing it?


"Leonard Caillouet" wrote in message
...
Post the model of the set and the locations of the cap and you might get
more specific help.

You likely have other caps that are bad.

Read the specs to find low esr caps. You will not likely find local
suppliers with a range of options in this area. It is not particularly
critical in most cases, but if you increase the voltage rating it may
become so. A 200V cap will generally have a higher esr than a 50V cap,
all else being equal.

Read the manufacturer's specs to find the esr value.

Leonard


"Leon Kiriliuk" wrote in message
...
My old "monitor" has a vertical deflection problem. I've noticed one of
the caps leaked. (the problem was the top 1/2 stretched, while the
bottom shrunk.. until the tube got warm.. but stayed almost the same).

According to the net, it's either Marcom or Elna caps (1uF 50V 105
degrees electrolytic).

So I went and put in there a 1uF 200V 105 degrees electrolytic. Now the
picture is shrunk to the middle 1/3 of the screen!

These caps are used to drive a AN5521. If I replace the IC, should that
fix my problem? are there any equivalent drop in IC's in case I can't
find it local to me?

Better yet, what are "low-esr" caps, and how can I tell them when
purchasing? Do I have to replace the 2 caps with the exact same "red"
caps, or are the ones I put in there now good enough?


Thanks!

On Sat, 27 Aug 2005 16:06:15 -0400, "Leon Kiriliuk"
put finger to keyboard and composed:

It's a Toshiba CX28400 / chassis tda9005.

I've replaced all the electrolytic caps on the entire board that are bigger
than the smallest ones.
Including all the ones the in the C3XX range.

I don't have a service manual for this chasis, and wanted to fix it.

Download a datasheet for the AN5521 from http://www.alldatasheet.com.
It has an application diagram that will most likely be similar to your
chassis. FWIW, some Toshiba sets had a vertical cramping problem due
to a dried out 2.2uF 50V cap near the jungle IC.


- Franc Zabkar
--
Please remove one 's' from my address when replying by email.