|
Post by jelosno on Sept 27, 2006 14:15:58 GMT
I was looking 'round on the net about chokes for the power supply. As far as I understood it the choke(s) will replace the resistors which are in the power supply after the rectifier and 'between' the filter caps. What would I need if I want to replace the following two resistors int the tubes power supply: 2.7K/5W 5% 4.7K MF 1% The chokes would have completely different values I guess since I can find only chokes with much lower ohm ratings and those are already huge heavy and very expensive. I have the feeling I am entirely wrong with my understanding of replacing resitors with chokes... Stefan
|
|
rickcr42
Fully Modded
Rest in peace my good friend.
Posts: 4,514
|
Post by rickcr42 on Sept 29, 2006 3:25:16 GMT
just got in from work and am totally 100% whipped (11:00 PM here and my day srated at 8:00,that is 15 hours for the math challenged ) so will give the answer in the A.M.,unless i pull another day from hell then will have to shift to Saturday ;D
|
|
rickcr42
Fully Modded
Rest in peace my good friend.
Posts: 4,514
|
Post by rickcr42 on Sept 30, 2006 17:44:04 GMT
got in a 10:45 last night so to say my brain is "fried" would not be off the mark (neither would saying I am shot in general ).In fact I had to nix an offer at a $600 payday as a friggin' "helper" on a nothing tile job today because I KNOW I will be about as useful as tits on a bull even though the extra cash would have been nice ....so rather than even try and attempt an answer other than a totally useless and 100% non valid "because it um sounds better um than the um resistor..." I will instead link to explanations better than any i can even on a good day provide www.audioasylum.com/forums/magnequest/messages/46.htmlmore added as my brain clears........................... BTW-those resistor values suggest LARGE filter caps which suggest solid state rectification yes ?
|
|
|
Post by jelosno on Sept 30, 2006 19:34:37 GMT
They will be 100uF Solen Fast Caps
solid rectifier is correct.
Stefan, half asleep because of our 16 day old boy...
|
|
rickcr42
Fully Modded
Rest in peace my good friend.
Posts: 4,514
|
Post by rickcr42 on Sept 30, 2006 20:09:55 GMT
been there man and even though I miss having "little ones" around the house (my boys are grown,youngest 17) I don't miss that part one bit.When my middle son was a new born up until almost a year old I NEVER got any sleep more than 3 hours per night. At the time I was doing residential construction (building new homes) and my job was an hour and a half commute away with a 6:00 A.M. start which meant up at 4:00,shower,grab a cup of java and out the door I go............with around 3 hours sleep !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! I was a lot younger then (thirty one and full of piss ) but still it kicked my ass pretty good considering the nature of the work (physical AND mental labor),the 3 hour round trip commute +10 hour days and when Rick gets tired he gets snarly so I spent the better part of a year being one of the most anti-social pricks ever to walk the planet with a hammer in my hand during work hours (and not too far away when not working )to make it even worse Weekends were damn near as bad because I would try to cram in a lot of living in a short time knowing I needed to be damn near trashed to sleep through the wailing (I wonder i never throttled the little bastard ) which meant that first year is almost a total blank with me being mostly a damn zombie for those weeks and months.I imagine I was also a piss poor husband then being either at work or hammered and ALWAYS in a "mood" ;D There are guys that I bump into every once in a while that remember me then and cross the street rather than deal with a face to face just in case I am still a prick Nope.Don't envy you man.You are learning to appreciate the little things like SLEEP but the good news is it gets waaaaay better and the now sleep deprevation unit will become a very interesting mini-person that will get you to do things you forgot were fun and will allow you to act like a kid and no one will even question it. act like that without having a little one close by and you could find yourself locked up tight in a room with padding on the walls
|
|
|
Post by jelosno on Sept 30, 2006 21:57:08 GMT
now that you mention it. I always wondered about that strange wallpaper here. So soft...
|
|
|
Post by jelosno on Sept 30, 2006 22:09:25 GMT
Is there a formula where I can find out the values of a choke that could replace the resistors? I have found this but it does not make too much sense to me since I don't know why the frequency of 100Hz was chosen: RC: G=s=(2*Pi*f) *R*C => s=(2*3,1416*100Hz) * 3000Ohm * 50µF = 94,25 LC: G=s=(2*Pi*f)² *L*C => s=(2*3,1416*100Hz) * 9H * 50µF = 177,65 The higher the value (177,65 vs. 94,25) the better If I assume the 100Hz make sense and the above formula is correct this would give me the following Henry values for a choke in my setup: C 100uF -> L 4.3 Henry -> C 100uF -> L 7.48 Henry -> C 100uF compared to C 100uF -> R 2.7K -> C 100uF -> R 4.7K -> C 100uF Can't be that easy. No way! Stefan
|
|
rickcr42
Fully Modded
Rest in peace my good friend.
Posts: 4,514
|
Post by rickcr42 on Oct 1, 2006 2:32:38 GMT
|
|
|
Post by jelosno on Oct 1, 2006 22:54:06 GMT
My formula above might show the 'value' for the filtering if there is anything like that. ;D What I can't find out it the data for the choke to lower the voltage like the resistor does. I have played around with the linked program. After a while I figured out where to change the values for the trasnsistor. I will have to wait for the parts to arrive to measure them correctly. As for the rectifier stage, no success since I have no clue what HEXFREDs are used there. I have tried all the available options in the menue but none give me the voltage ratings listed in the schematic of the EAR+... Back to stand by/waiting mode... Stefan
|
|