[Elecraft] About my capacitor failure (etc.) issue:

[Bob McGraw K4TAX]

I had a ham mention to me that this power supply blew up.  He was somewhat annoyed when I ask if anyone was injured in the explosion.  

Folks, for us trying to assist with technical issues, please give complete and accurate descriptions.  You will get better answers. 

Bob, K4TAX


Sent from my iPhone

> On Apr 19, 2020, at 10:33 PM, Jim Rhodes <jimk0xu at gmail.com> wrote:
> 
> Or sometimes, just to get your attention, they will short out then
> explosively go open with a bang. The is usually no doubt figuring out which
> component is bad.
> 
>> On Sun, Apr 19, 2020, 19:56 Christopher Hoover <ch at murgatroid.com> wrote:
>> 
>> opens in my limited experience.
>> 
>>> On Sun, Apr 19, 2020 at 4:26 PM Adrian <vk4tux at gmail.com> wrote:
>>> 
>>> When you say 'blow' are you saying it short circuits internally or open
>>> circuits internally due to the event      ?
>>> 
>>> 
>>> Adrian Fewster
>>> 
>>> On 20/4/20 8:07 am, Christopher Hoover wrote:
>>>> You might want to replace the bridge rectifier in that new 35A power
>>> supply.
>>>> 
>>>> Yep, right out of the box.
>>>> 
>>>> At some point, Astron started shipping RS-35A's with a 25A bridge
>>>> rectifier.   They paralleled two out of four of the 25A diodes twice
>> over
>>>> to make, supposedly, a pair of 50A diodes for center-tapped full-wave
>>>> rectification.  That's not good engineering practice as the diodes in
>>> each
>>>> pair will not share current equally because of differences in Vf and
>>>> tempco.     Once one blow, the other will blow shortly after.
>>>> 
>>>> After I fixed my own RS-35A with this problem, I've helped several
>> other
>>>> hams fix this same problem in theirs.  Not a random sample, as this is
>>> just
>>>> folks on my local machine and in local clubs.
>>>> 
>>>> You can get a 50A bridge in the same package for under $3.
>>>> 
>>>> Perhaps Astron has fixed the problem since ....
>>>> 
>>>> 73 de AI6KG  -ch
>>>> 
>>>> 
>>>> 
>>>> 
>>>> On Thu, Apr 16, 2020 at 10:28 AM Ray Albers <rayalbers at gmail.com>
>> wrote:
>>>> 
>>>>> Many to all who posted/responded to my recent post about an
>> electrolytic
>>>>> capacitor failure in my power supply.  Lots of very interesting
>> reading
>>>>> about peoples' industry experiences - thank you!
>>>>> 
>>>>> Several have pointed out that using a 20A supply with my K3/100 is
>>> pushing
>>>>> close to (or over!) the limit.  Even though I am measuring just 16A at
>>> the
>>>>> power level I'm running (and not running anything but the K3 on this
>>>>> supply) I agree that I'm skirting the edges. So even though I've been
>>>>> getting away with it for a long time, this morning I ordered a 35A
>>> supply.
>>>>> I'll probably sleep better.
>>>>> 
>>>>> 73
>>>>> Ray K2HYD
>>>>> 
>>>>> <
>>>>> 
>>> 
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