[Amps] SB-200 power supply diodes

[Carl]

I mentioned the 1N5408 holes 2 days ago at the start of the thread. I still 
prefer them to 1N4007's as their surge current survivability far exceeds the 
1N4007. After all the idea is to not have smoke if a cap shorts or a tube 
lets go. The amps breakers pop and should save the transformer.

Carl
KM1H



----- Original Message ----- 
From: "Vic K2VCO" <vic at rakefet.com>
To: <amps at contesting.com>
Sent: Saturday, March 26, 2011 10:49 AM
Subject: Re: [Amps] SB-200 power supply diodes


>I agree. I didn't think about the holes when I recommended the 1n5408's. 
>They have a
> higher current rating, of course, but as Jim says, it won't make any 
> difference in the SB200.
>
> On 3/26/2011 6:24 AM, Jim Garland wrote:
>> Kathy,
>> I'd advise replacing the diode string in your SB-200 with 1N4007 diodes
>> instead of 1N5408. Not that there's anything wrong with the 1N5408, but 
>> the
>> holes in the circuit board will have to be drilled out to make them fit. 
>> The
>> 1N4007 will be a perfect fit, and with  a 1A/1000V rating, will be more 
>> than
>> adequate for an SB-200. You should probably also replace the elderly
>> electrolytics in the amplifier while you have it apart.
>> 73,
>> Jim W8ZR
>>
>>> From: Kathy Bookmiller<wb2aio at yahoo.com>
>>> Subject: [Amps] SB200 diodes
>>> To: amps at contesting.com
>>> Message-ID:<795630.36304.qm at web59714.mail.ac4.yahoo.com>
>>> Content-Type: text/plain; charset=iso-8859-1
>>>
>>> Thanks to everyone for their replies. I'm going to order them from 
>>> Mouser
>> and replace them
>>> all as that is the consensus of the replies I received both on-list and
>> off. Did take a run over
>>> to my local RS store and they had some that were close to the 1n5408s in
>> spec, but only a 3
>>> pack of them, so will order them all from Mouser.? That seems to be the
>> norm for RS. It
>>> seems about every time I go in there for some parts, they'll have them 
>>> in
>> those drawers in
>>> the back, but only one or none is inside the compartment.
>>> While waiting for them to show, maybe I'll finally get into my old 
>>> NCL2000
>> that is loosing
>>> it's drive and has been sitting on the repair bench for a year:) That is
>> how I ended up buying
>>> the SB200 when it showed up on Craigslist here last summer, while 
>>> waiting
>> for a new set of
>>> tubes to show up.
>>> So I'll spend the weekend looking for the odd band fill in the WPX 
>>> contest
>> and checking the
>>> capacitors in the SB200 and cleaning off the board of the old diodes.
>>> 73,
>>> Kathy
>> *************
>>
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>
> -- 
> Vic, K2VCO
> Fresno CA
> http://www.qsl.net/k2vco/
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