I just went around some local 1Hr Photo places and got 6 of the disposable cameras they throw away. Inside each is a nice alkaline battery(!) and a 160uF 330V rubycon cap.
From what I have read on usenet, (yay google) it appears they are not the best for ripple handling, so I will not be using them directly after the rectifier; but as a reservoir cap that follows the choke, I think they would be great!
I am thinking about two in series to give 80uF with a 200K resistor across each. Three of these 80uf units in parallel would give a nice 240uF which would be run at only ~460V, for a massive safety margin.
Does this sound sensible?! Saves me buying a $50 can cap.
From what I have read on usenet, (yay google) it appears they are not the best for ripple handling, so I will not be using them directly after the rectifier; but as a reservoir cap that follows the choke, I think they would be great!
I am thinking about two in series to give 80uF with a 200K resistor across each. Three of these 80uf units in parallel would give a nice 240uF which would be run at only ~460V, for a massive safety margin.
Does this sound sensible?! Saves me buying a $50 can cap.
Ditto Sheldon, but you have to admit the price is right!
There are some larger types available 525V/500u from Mallory IIRC, that are used in professional flash assemblies, and are quite reasonably priced. Very tough and much better sonics. If you luck across some of these grab them too. Sorry no URL (lost it in last years HDD crash) but there is an article or two on the late Doc Gizmo's site about them and they were oft recommended by Walt Jung and co in old Audio Amateur articles.
There are some larger types available 525V/500u from Mallory IIRC, that are used in professional flash assemblies, and are quite reasonably priced. Very tough and much better sonics. If you luck across some of these grab them too. Sorry no URL (lost it in last years HDD crash) but there is an article or two on the late Doc Gizmo's site about them and they were oft recommended by Walt Jung and co in old Audio Amateur articles.
Cheap Photoflash capacitors:
http://www.allelectronics.com/cgi-bin/category.cgi?category=140750&type=store
Jakob E.
http://www.allelectronics.com/cgi-bin/category.cgi?category=140750&type=store
Jakob E.
Logically, a photoflash capacitor should require low ESR, making it ideal for bypassing output stages. Conversely, it is not required to survive nearly as many charge/discharge cycles, so its ripple current capacity could be poor. I suspect that a photoflash capacitor is probably good for smoothing and occasional pulses, but not for repetitive ripple duty.
Well, I went and got a whole lot more throw away cameras;
I now have
7 x CM (?) 100uF 330V (rated -20*C to 55*C)
12 x Rubycon 120uF 330V
8x "Photo" 120uF 330V
2x Rubycon 160uF 330V
and a couple of miscellaneous ones with no markings. I think I will build a cap board and see how it goes. Put it well away from heat sources to keep it cool.
Oh, and these things can store a lot of energy! I shorted one out with a screwdriver and there was a massive blue spark and a good smell of ozone, I used a resistor after that!
I now have
7 x CM (?) 100uF 330V (rated -20*C to 55*C)
12 x Rubycon 120uF 330V
8x "Photo" 120uF 330V
2x Rubycon 160uF 330V
and a couple of miscellaneous ones with no markings. I think I will build a cap board and see how it goes. Put it well away from heat sources to keep it cool.
Oh, and these things can store a lot of energy!
I shorted one out with a screwdriver and there was a massive blue spark and a good smell of ozone, I used a resistor after that! 
EC8010 said:
Actually they have quite high ESR on the order of ohms. This slows the flash pulse and lowers peak current, also preventing damage (I suppose).
They also have very low temp ratings circa 50-60°C, not a very good indicator of life.
Nonetheless, of you go to PSUD and punch in 5 ohms ESR for the filter caps, it still works fine. So don't worry much about high ESR caps.
Tim
In high-rel regulator designs for tube stuff, you'll often see a resistor of a few ohms in series with the output cap- Joe Curcio's power amp regulators come to mind as an example. Think of that ESR as a component-saving bonus. A few ohms of PS source resistance at very high frequencies for a tube amp is not really a terrible thing, given the current draw involved, and it can dramatically increase pass device reliability.
I remember ads from hifi mags several yrs ago-Croft was proud to say that photoflash caps are used in their preamps supply's.
just be sure that cap in case is from good manufacturer and use it.
this is not realy needed to think about all mumbojumbo high end crap;
think DIY-you can always change ,if you find better solution-hehe especially if better is cheaper
just be sure that cap in case is from good manufacturer and use it.
this is not realy needed to think about all mumbojumbo high end crap;
think DIY-you can always change ,if you find better solution-hehe especially if better is cheaper
Re: FLASH...
we all know what paper can handle
I think that some sort of "Super Micro(or some bigger model put there instead of Micro)" was in question in this add.fdegrove said:Hi,
Nope, Glenn never did use those caps...
I agree the blabla said so but in reality that never incarnated.
Cheers,
we all know what paper can handle
Hell, No.
Hi,
Well, if you must know I'm partially responsible for that...back in the mid-eighties photoflash caps were usually about the best caps you could get.
The preamp you refer to is quite likely the "Mega Micro".
A dual mono design that beats virtually anything around even to this day.
I helped design it and also made it MC cart compatible.
If you happen to own one of those, hang on to it and if you need advise on how to improve it send me an e-mail.
Cheers,
Hi,
Well, if you must know I'm partially responsible for that...back in the mid-eighties photoflash caps were usually about the best caps you could get.
The preamp you refer to is quite likely the "Mega Micro".
A dual mono design that beats virtually anything around even to this day.
I helped design it and also made it MC cart compatible.
If you happen to own one of those, hang on to it and if you need advise on how to improve it send me an e-mail.
Cheers,
Re: HELL, NO.
in these days I was in dipers,at least in tube world.
hehe,but that dont stop me to dream of "all those stuff".
in a meantime I learn something from all old books and numerous schematics I digg,so I can build my own .
But,I always admired look and attitude of Crofts-"not bigger than life",at least I figured it in that way
that doesn't mean that I'll not be gratefull for Mega Micro schmtc
tnx to offer ,but I not have anything from Croft;fdegrove said:Hi,
Well, if you must know I'm partially responsible for that...back in the mid-eighties photoflash caps were usually about the best caps you could get.
The preamp you refer to is quite likely the "Mega Micro".
A dual mono design that beats virtually anything around even to this day.
I helped design it and also made it MC cart compatible.
If you happen yo own one of those, hang on to it and if you need advise on how to improve it send me an e-mail.
Cheers,
in these days I was in dipers,at least in tube world.
hehe,but that dont stop me to dream of "all those stuff".
in a meantime I learn something from all old books and numerous schematics I digg,so I can build my own .
But,I always admired look and attitude of Crofts-"not bigger than life",at least I figured it in that way
that doesn't mean that I'll not be gratefull for Mega Micro schmtc
Re: FLASH PINT...
but,I stil like to lay my eyes on any new (to me ) schematic,to see and think about other's ways to design .
personally-I have not much respect for most of audio stuff makers,but (as I say earlier) I admire honest and inventive and lucid makers-as you boyz at Croft were (are ).
I was buyed with just pictures (of innards) of Micro in some local HiFi magazine 100 yrs ago-plain ,simple and nice.
my email is chokyATeunet.yu
tnx in advance
in last several yrs I didn't build anything from someone other's schmtcfdegrove said:Hi,
Not that I mind sending it but the circuit diagram alone won't make for a good sounding preamp...
Much attention was paid to wire gauges, passive component quality, layout, grounding etc.etc...
Send me an e-mail and I'll forward to diagrams.
Cheers,
but,I stil like to lay my eyes on any new (to me ) schematic,to see and think about other's ways to design .
personally-I have not much respect for most of audio stuff makers,but (as I say earlier) I admire honest and inventive and lucid makers-as you boyz at Croft were (are ).
I was buyed with just pictures (of innards) of Micro in some local HiFi magazine 100 yrs ago-plain ,simple and nice.
my email is chokyATeunet.yu
tnx in advance
Hi,
Well, consider it done...for further 'splanations e-mail me... Glenn wouldn't give a sh*t anyway...
Keep in mind that all he circuitry is P2P and passive components and circuit layout are mucho importanto for the final results...
The circuits I send will be good for MM cartridges only...
For MC using valves ring my bell again...you can actually build it in and I can advise you how to optimise the combination.
Cheers,
Well, consider it done...for further 'splanations e-mail me... Glenn wouldn't give a sh*t anyway...
Keep in mind that all he circuitry is P2P and passive components and circuit layout are mucho importanto for the final results...
The circuits I send will be good for MM cartridges only...
For MC using valves ring my bell again...you can actually build it in and I can advise you how to optimise the combination.
Cheers,
fdegrove said:Hi,
Well, consider it done...for further 'splanations e-mail me... Glenn wouldn't give a sh*t anyway...
Keep in mind that all he circuitry is P2P and passive components and circuit layout are mucho importanto for the final results...
The circuits I send will be good for MM cartridges only...
For MC using valves ring my bell again...you can actually build it in and I can advise you how to optimise the combination.
Cheers,
Just an update... I won't be using the photoflash caps, I have just bought for $10 a used, enormous switching power supply (5V at 250A! 
) that has 4x 560uF 450V caps in it. Two of them in series should do the trick nicely. It all looks in good condition, seems a shame to break it up, but I really have no use for 5V!
I might still use a couple of the photoflash caps in the preamp section.
) that has 4x 560uF 450V caps in it. Two of them in series should do the trick nicely. It all looks in good condition, seems a shame to break it up, but I really have no use for 5V!I might still use a couple of the photoflash caps in the preamp section.
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