• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Ordering from Justradios.com

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Plenty safe as far as malware/tracking is concerned I was surprised to find it had no trackers ,highly unusual , usually most websites have at least Google in various forms.


As far as quality it looks high to me --not the highest but its pretty good .


Mica capacitors were much used in old tube radios in the RF section for high stability ,the modern dipped ones are reliable.


Don't like polyester though stick to polypropylene .


If you are thinking along mica lines for audio then go for LOW values of COG Ceramic approved by several of the big audio design engineers and approved by D.Self.
 
Miec are the only ones who sell electrolytic capacitors that are rated at low uf and high voltage like 33 uf 450v.

Not true. All the major manufacturers sell caps rated at 450v in standard values such as 10uf, 22uf, 33uf, 47uf, etc.

I usually order from Digi-Key because they offer free shipping if you order via regular mail (not online) and pay using either personal check or money order. This only applies to orders from the US and Canada.

This can result in significant savings, especially if you only need to order a few parts and it really doesn't slow down the ordering process much at all.

Most people are not aware of this since it's somewhat hidden under "Terms and Conditions" in the fine print at the bottom of their website. When you send in an order it's a good idea to mention the specific section.

Here's what it says:
 

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Hello from Greece! I buy these capacitorw from hificollective.co.uk I buy 4 pc 100uf/600v. I use these capacitors in my tube amp,with out problems! I use ss rectification,the raw voltage is about 440vdc. I use these in parallel in pi circuit 200uf//10H//200uf. This amp work from 2015,without problem! I think these things is taiwan made.
 
You haven't said what you're working on. If you have a schematic, please post it.

What's the capacitance and voltage rating of the cap(s) you're replacing?

If you're replacing an existing stock cap with the same value it's fine. Going a bit higher in voltage is OK but not lower. If it's an old unit the capacitance may not match exactly but you can use a standard modern value that's close. For instance, a vintage 30uf cap can be replaced with a modern 33uf.

If the original cap was 8uf then the one you linked is OK but I would point out that its voltage rating is 1300v, which is quite high. Unless you really need a cap that's rated at such high voltage it would be better, and considerably cheaper, to use a lower voltage cap.

If it's a typical old radio I'd suggest you just use a quality electrolytic, not a film cap.
 


You might not know this but in a typical tube radio with a fullwave tube rectifier used the one immediately after the rectifier is called a reservoir capacitor and the one after the choke or large wattage resistor the smoothing capacitor.


What is your tube rectifier ?? every rectifier has its range of values of capacitor get it wrong and the rectifier becomes faulty.
 
What do you mean by range of values.


I noticed large values of mfd were being advised by some in different threads while nothing is stopping you doing that it does have its engineering drawbacks when it comes to vacuum tube technology when referring to tube rectifiers .


Take the extremely well known rectifier for late ,30,s up to the ,50,s as installed in many tube radios the -


5Z4G a maximum of 32/50mfd is advised (depending on the maker ) with a minimum-of 380 ohm series resistor .
Thats Mullard,s specs a highly respected European / UK manufacturer .


TV rectifiers had higher values



There are slight variations but unless you don't care about the rectifier tube in your hi-fi dont install solid state equivalents running into many 100,s/1000,s of mfd.
 
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