Okay thanks--I didn't look far enough back in time. I'll go into the
'30s handbooks. tnx
Rob
K5UJ
On Sat, Apr 14, 2012 at 7:44 PM, Carl <km1h@jeremy.mv.com> wrote:
> In the 30's when the mercury vapor tubes came along. I have QST complete
> from 1926 to present plus most ARRL and the "other" HB and read thru the
> oldies about 10 years ago after having them in storage since the 70's or so.
>
> Your buddy Don has commented a few times also when he isnt on one of his OWL
> kicks (-;
>
>
> Carl
> KM1H
>
>
>
> ----- Original Message ----- From: "Rob Atkinson" <ranchorobbo@gmail.com>
> To: "Carl" <km1h@jeremy.mv.com>
> Cc: "Roger (K8RI)" <k8ri@rogerhalstead.com>; <amps@contesting.com>
> Sent: Saturday, April 14, 2012 6:19 PM
>
> Subject: Re: [Amps] Filter Capacitors
>
>
>> I'm trying to find out more about this but so far have only found
>> instruction on avoiding ripple frequency resonance with a choke input
>> filter. What were the old handbooks you looked at? I was looking at
>> the '51 ARRL handbook. Thanks,
>>
>> 73
>>
>> Rob
>> K5UJ
>>
>> On Fri, Apr 13, 2012 at 9:40 AM, Carl <km1h@jeremy.mv.com> wrote:
>>>
>>> A choke is not a good idea unless great care is taken to
>>> eliminate/minimize
>>> the switching spike which is present with tube and SS rectifiers. A scope
>>> is
>>> mandatory especially if the choke and caps are not well overated for
>>> voltage.
>>>
>>> For decades this spike has been mostly ignored in literature and finally
>>> saw
>>> daylight again when more boatanchor amps were being built and then the
>>> audio
>>> types got involved and developed their own versions of reality.
>>>
>>> I first noticed it about 10 years ago when checking ripple in a 2700V PS
>>> and
>>> had to dig into the old handbooks and QST's and saw the "ancients" knew
>>> all
>>> about it. I hadnt built a choke input supply since the late 50's and that
>>> was simply using WW2 surplus from a BC-610 so obviously the design work
>>> was
>>> already done.
>>>
>>> Carl
>>> KM1H
>>>
>>
>>
>> -----
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>>
>
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