old capacitor  - Page 1
Forum section: electronics / repair

author: alwayslearning
author_rank: Contributor
timestamp: March 28, 2016, 12:29:40 am
content: trying to identify this old thing from the 50s to replace with a new one .i dont know how to read the values to match with a new one and the local shops have no idea. not much info on the web either .

author: Tomorokoshi
author_rank: Super Contributor
timestamp: March 28, 2016, 12:44:13 am
content: Seems to be:Capacitance: 32 micro-FaradWorking voltage: 300 VPeak voltage: 350 VMade in Australia!

author: alwayslearning
author_rank: Contributor
timestamp: March 28, 2016, 12:51:55 am
content: thanks heaps ,hard to find info about these,now i can read them with some confidence.

author: uncle_bob
author_rank: Unknown
timestamp: March 28, 2016, 12:55:36 am
content: Quote from: Tomorokoshi on March 28, 2016, 12:44:13 amsHiOk, so the key feature is that the replacement *must* be made in Australia.Any modern part at >= 32 uF and >= 350V should do just fine. I would not go over 2X the marked uF number, but finding the exact value is not essential in most cases. Voltage rating steps have changed back and forth over the years as has the whole "do you list max or list working" for the voltage number. The 300V number is the one you used to see more often. It was always confusing going from an outfit that marked one to a group that marked the other. Any more, the cost delta is very small. Go for a bit higher voltage rating.Bob

author: alwayslearning
author_rank: Contributor
timestamp: March 28, 2016, 06:34:15 am
content: just had a break through ,someone passed this on to me .

author: VK5RC
author_rank: Unknown
timestamp: March 28, 2016, 07:53:03 am
content: There are quite a few vintage / tube groups if you are looking for these type parts / circuits etc. e.g.http://www.hrsa.asn.au/h_link.htm

author: wraper
author_rank: Unknown
timestamp: March 28, 2016, 07:55:35 am
content: Looks more like 82, not 32uF. Also 32 is not a standard capacitance value but 82 is.

author: Cubdriver
author_rank: Unknown
timestamp: March 28, 2016, 08:13:18 am
content: I dunno, it looks like 32 to me. The edges on the digit (near the top at least) appear to be sharp and look to match those on the other two 'threes' on the label. And while 32uF might not be a standard value now, it rings a bell and I don't think it was uncommon back in the tube days.For what it's worth.-Pat

author: SeanB
author_rank: Super Contributor
timestamp: March 28, 2016, 08:20:30 am
content: As it is a valve set you can use almost any modern electrolytic, 47uF 400v is a very common value. However you will need to add a series resistor of around 10-47R 1W in series with the capacitor, as the ESR of the modern one is so low compared to the old one that the resistor is needed to reduce the peak pulse current through the rectifier valve.

author: vk6zgo
author_rank: Super Contributor
timestamp: March 28, 2016, 08:28:56 am
content: Quote from: wraper on March 28, 2016, 07:55:35 amIt's definitely 32uF,I've handled,& replaced hundreds of them.8uF,16uF,24uF & 32uF were standard values of electrolytic capacitor values in Australia when that cap was madeNote the steps of 8uF,which was maybe something to do with construction methods.Higher values,which were less common,mostly reverted to multiples of 100,although 220uF was in the mix for some reason.

author: alwayslearning
author_rank: Contributor
timestamp: March 28, 2016, 09:07:18 am
content: its 32 for sure ,read much easier than in the photo.this has been a good learning curve