Testing capacitors.
- pre65
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#1 Testing capacitors.
I have three Russian 4uf PIO caps on the Pre project.
I would like to test the two used as coupling caps, is there a way of doing so with a DMM ?
If I use a DC supply then no voltage should pass, but if I use an AC supply then it should pass. Have I got that right ?
I would like to test the two used as coupling caps, is there a way of doing so with a DMM ?
If I use a DC supply then no voltage should pass, but if I use an AC supply then it should pass. Have I got that right ?
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
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Edmund Burke
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- Mike H
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#2
If DMM is on AC Volts, yes. Really needs some sort of resistor as well on the output side as a 'load'.
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
- IslandPink
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#3
Would it be worth mentioning that a 4uF Russian paper in oil used as a coupling cap at pre-amp voltage levels could sound pretty poor ?
If you could go down to 1uF, you might get more music through .
If you could go down to 1uF, you might get more music through .
"Once you find out ... the Circumstances ; then you can go out"
- pre65
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#4
I think Nick settled on 3.3uf as the cap value and those 4uf Russian MBGP-2 caps were the nearest I had in stock.IslandPink wrote:Would it be worth mentioning that a 4uF Russian paper in oil used as a coupling cap at pre-amp voltage levels could sound pretty poor ?
If you could go down to 1uF, you might get more music through .
I'm thinking of some "monster" Russian K75-10 PIO hybrid caps (2.2uf) for the new preamp. The 500v (AC) ones are huge but the 250v (AC) ones are a bit smaller.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
- pre65
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#5
I could bypass them I suppose, I've just found a couple of Russian OCK73-16b 0.1uf 1600v caps in a box that Adrian (Buddam) gave me.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
#6
I used 3u3 as I was unsure what it might drive. You should know, and can calculate accordingly.pre65 wrote:I think Nick settled on 3.3uf as the cap value and those 4uf Russian MBGP-2 caps were the nearest I had in stock.IslandPink wrote:Would it be worth mentioning that a 4uF Russian paper in oil used as a coupling cap at pre-amp voltage levels could sound pretty poor ?
If you could go down to 1uF, you might get more music through .
I'm thinking of some "monster" Russian K75-10 PIO hybrid caps (2.2uf) for the new preamp. The 500v (AC) ones are huge but the 250v (AC) ones are a bit smaller.
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
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#7
Phil, 2 x SA ClarityCaps 3.3uF from HFC won't cost a fortune. (Nick used the ESA's versions, do cost more)
Didn't realise or forgot you were using Russian PIO's, might in some way explain why it hasn't been sounding too good to date
Didn't realise or forgot you were using Russian PIO's, might in some way explain why it hasn't been sounding too good to date
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
#8
I used MR, not ESAMike H wrote:Phil, 2 x SA ClarityCaps 3.3uF from HFC won't cost a fortune. (Nick used the ESA's versions, do cost more)
Didn't realise or forgot you were using Russian PIO's, might in some way explain why it hasn't been sounding too good to date
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
- pre65
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#9
I'll have a look in my boxes of capacitors and see what I can find.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
- pre65
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#10
I could not sleep, so I've been reading MJ, and although there is no formula, he suggests that for connecting to a "typical" valve amp a cap greater than 470nf (0.47uf), so looking through my box I have got a couple of 680nf (0.68uf) Clarity cap SA.
So Marks suggestion of 1uf was about right. Thanks for the tip Mark and to Nick for making me think about the value.
I'll try it later.
So Marks suggestion of 1uf was about right. Thanks for the tip Mark and to Nick for making me think about the value.
I'll try it later.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
#11
Its just a CR high pass filter between the C of the coupling cap and the R of the following load. Don't know what edition of MJ you have, but I will put my own money on the fact that it containspre65 wrote:I could not sleep, so I've been reading MJ, and although there is no formula, he suggests that for connecting to a "typical" valve amp a cap greater than 470nf (0.47uf), so looking through my box I have got a couple of 680nf (0.68uf) Clarity cap SA.
So Marks suggestion of 1uf was about right. Thanks for the tip Mark and to Nick for making me think about the value.
I'll try it later.
f = 1 / ( 2 * pi * c * r )
Whenever an honest man discovers that he's mistaken, he will either cease to be mistaken or he will cease to be honest.
- pre65
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#12
It's probably in there somewhere.
I was reading in the preamp section.
Soldering iron is awaiting me.
I was reading in the preamp section.
Soldering iron is awaiting me.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
- Mike H
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#13
So you did, my badNick wrote:I used MR, not ESA
Memory is crap
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"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
- pre65
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#14
Think yourself lucky Mike, all I seem to remember IS shit.
(only joking )
(only joking )
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)