AudioRoundTable.com: Group Build

Home » Audio » Group Build » Filament Caps

Show: Today's Messages :: Navigator :: Polls
E-mail to friend

Filament Caps [message #30812]

Fri, 04 March 2005 06:47

Manualblock
Messages: 4973
Registered: May 2009

Illuminati (13th Degree)

Anyone; while I wait for the 10k caps to be delivered; why can't I use the original 4.7K filter caps again??

Report message to a moderator

That's what I used [message #30813 is a reply to message #30812]

Fri, 04 March 2005 08:03

colinhester
Messages: 1349
Registered: May 2009
Location: NE Arkansas

Illuminati (3rd Degree)

I used what was on the heater schematic, which was 4.7 mF (4700uF)and I believe 25V rating. See link below and remember the resistors were changed to 2 and 2 ohm......Colin

http://audioroundtable.com/GroupBuild/messages/397.html

Report message to a moderator

Re: That's what I used [message #30814 is a reply to message #30813]

Fri, 04 March 2005 08:22

Manualblock
Messages: 4973
Registered: May 2009

Illuminati (13th Degree)

Thanks Colin; I am somewhat upset now. Where did the 10k come from??? I am sitting here like a nitwit waiting for some caps I don't even need!
I have that schematic but somehow I got the impression it was changed.
Jeez.

Report message to a moderator

That's what I used [message #30815 is a reply to message #30814]

Fri, 04 March 2005 08:29

PakProtector
Messages: 935
Registered: May 2009

Illuminati (2nd Degree)

4k7 uF is aceptable, so is 10k uF. I ran a bit on the iffy side with 10k uF @ 16 V. I hope yo guys can see the risk in that. L-C filter with ~18 vac will over-voltage them in a big way if no load is applied to the filter.

10k was just as easy for me to get as 4k7. You'll be fine w/either. I keep forgetting to limit your options, and act like a dictator.

Gilligan, dreaming, promises the crowd, "this, that, and the other thing..."
regards,
Douglas

Report message to a moderator

Less ripple w/10k uF [message #30816 is a reply to message #30815]

Fri, 04 March 2005 08:47

colinhester
Messages: 1349
Registered: May 2009
Location: NE Arkansas

Illuminati (3rd Degree)

Ran a PSU simulation using 4.7k vs. 10k uF in the RCRC heater. 10k gives a lot less ripple if used in the first position (the one closest to the diodes) A change in ripple was not even noticed if the value was increased in the second position (cap closest to load) From this, you might want to hold off and use the 10k's. It sure looks like you'll be better off.....Colin

Report message to a moderator

Re: Less ripple w/10k uF [message #30817 is a reply to message #30816]

Fri, 04 March 2005 09:06

Manualblock
Messages: 4973
Registered: May 2009

Illuminati (13th Degree)

Dictator; thats good, I like that. I want to get going here, before you guys move on and I am just a faint echo in the distance "Hallooo?"
I may need to post photo's for help; is that too much, like hogging the action? Don't be afraid to tell me; I'm not sensitive.
Also it don't matter; as far as perfection; all will change eventually anyway;no?

Report message to a moderator

Re: Less ripple w/10k uF [message #30818 is a reply to message #30817]

Fri, 04 March 2005 10:21

PakProtector
Messages: 935
Registered: May 2009

Illuminati (2nd Degree)

Hey-hey!!!,
I'll help if you post photo's or not. Until You're satisfied.
regards,
Douglas

Report message to a moderator

Re: Less ripple w/10k uF [message #30819 is a reply to message #30818]

Fri, 04 March 2005 11:15

Manualblock
Messages: 4973
Registered: May 2009

Illuminati (13th Degree)

"I just can't seem to be satisfied!"; Muddy Waters.(M'Kinley Morganfield.)

Report message to a moderator

Is cap size worth increasing in heater PS? [message #30820 is a reply to message #30815]

Fri, 04 March 2005 13:18

colinhester
Messages: 1349
Registered: May 2009
Location: NE Arkansas

Illuminati (3rd Degree)

From a PSU simulation, it looks like ripple is really reduced by increasing the size of the capacitor that is closer to the diodes - not quite as much as the LCRC but still reduced. In your opinion would it be worth John replacing the first cap with the 2 10uF in parallel and using one of his 4.7uF in the second position. I'm thinking of adding a 10uF in parallel across the 4.7uF I already have installed, giving a total capacitance of 14.7uF.....Colin

Report message to a moderator