Small cap replacements for Sony CRT

[ckrtech]

Hey guys -

I am currently recapping an old Sony Trinitron CRT - some of the caps inside are crusty and have failed while others are just getting a refresh.

I have a list for the primary board, tuner, and neck board, and I need some caps with lower uf values.

50V with 0.1, 0.22, 0.33, and 0.47.

Most of the ones coming up on Digikey are BP caps. There are a few ELNA caps that fit the stats, but - Should I look to jump to something more common like 2.2uf?

I've attached relevant files - a photo of the caps I have left, the XLS spreadsheet with cap data, and schematic of the TV circuit (if interested)

[goontron]

Re: Small cap replacements for Sony CRT

Go for film caps.

[ckrtech]

Re: Small cap replacements for Sony CRT

Hmm. Price-wise, perhaps bumping to 100v max would work so long as diameter and lead spacing stays the same? I assume some of the lytics' stats would change a bit, but I don't know off the top of my head how much upping the voltage rating on a low uf electrolytic would affect the applicable circuit.

Bumping to 100v greenlights me to Nichicon

[R_J]

Re: Small cap replacements for Sony CRT

What is so special about those caps that you can't use the ones at digikey, I found about 60 of each value at 50volt to choose from
IE https://www.digikey.com/products/en/...=1&pageSize=25

[ckrtech]

Re: Small cap replacements for Sony CRT

Ahh. I was probably filtering for Active as opposed to Obsolete but neglected Not for New Designs, and that filter was activated 30 capacitors back. Cool

[mariushm]

Re: Small cap replacements for Sony CRT

Buy 63v or higher voltage rating capacitors, you don't have to stick to 50v

Just check for 63v rated capacitors on Digikey, and all your values can be found on Digikey.

I would be reluctant to replace them with ceramic or film capacitors, in case the much lower ESR would affect things. Such electrolytic capacitors would normally have something like 1..5 ohm ESR and ceramic and film capacitors have very low esr, under 0.1 ohm typically.

[momaka]

Re: Small cap replacements for Sony CRT

Go for film caps.

+10

50/63/100V film caps with those capacitances should be fine for replacing these (and easy to find too).

I would be reluctant to replace them with ceramic or film capacitors, in case the much lower ESR would affect things. Such electrolytic capacitors would normally have something like 1..5 ohm ESR and ceramic and film capacitors have very low esr, under 0.1 ohm typically.

The film caps' ESR won't be an issue with any of the CRT circuits - at least I can't think of one.
Most of these small caps are used for signal coupling rather than filtering. And they probably used electrolytics only because they're cheaper.

I'd stay clear of ceramics, though, as some of them have capacitance that is fairly temperature-dependent.