Carl,
>From the "how stupid can a person get" category - I managed once to get the
B+ lead to touch the grid current meter. That was exciting.
Fortunately, I had liked RM's advice on clamping diodes "I like big big
diodes" - and so had a pair of the 6A variety across the meter. I think the
pulse current rating is about 9 million amps or something.
Anyway, I needed to replace a couple of the meter wires - but the meter
itself was unharmed.
Got a nice big black mark near the terminal though... And another lesson in
respecting HV.
73/jeff/ac0c
--------------------------------------------------
From: "Carl" <km1h@jeremy.mv.com>
Sent: Monday, November 09, 2009 7:41 PM
To: "Jim Carr" <n7fcf@hctc.com>; <dezrat1242@yahoo.com>;
<amps@contesting.com>
Subject: Re: [Amps] B- questions
> A reverse connected 1N4007 or any similar rectifier diode can be
> considered
> a zener also and they are used that way in amplifiers to set the operating
> bias. An off the shelf zener conducts at a much higher voltage for their
> lowest values. Ive used Schottky's in a meter protection experiment but
> didnt see any added benefit over a 1N400x. Both always protected the
> meters
> tested.
>
> Carl
> KM1H
>
>
>
> ----- Original Message -----
> From: "Jim Carr" <n7fcf@hctc.com>
> To: "Carl" <km1h@jeremy.mv.com>; <dezrat1242@yahoo.com>;
> <amps@contesting.com>
> Sent: Monday, November 09, 2009 6:47 PM
> Subject: Re: [Amps] B- questions
>
>
>> Carl,
>> Another one how about reverse parallel zeners? RCA used a system of
>> reverse parallel zeners accros the 105v 120 cycle signal from the
>> diferential anplifiers to the printed circuit motors of their computor
>> tape drives to saw off the noise spikes rideing on the waveform.
>> Jin
>> N7FCF
>> ----- Original Message -----
>> From: "Carl" <km1h@jeremy.mv.com>
>> To: <dezrat1242@yahoo.com>; <amps@contesting.com>
>> Sent: Monday, November 09, 2009 7:34 AM
>> Subject: Re: [Amps] B- questions
>>
>>
>>> The term I learned in industry is reverse parallel. Anti parallel seems
>>> to
>>> be a ham invention and likely European in origin in line with anti
>>> clockwise
>>> (-;
>>>
>>> Carl
>>> KM1H
>>>
>>>
>>>
>>> ----- Original Message -----
>>> From: "Bill, W6WRT" <dezrat1242@yahoo.com>
>>> To: <amps@contesting.com>
>>> Sent: Monday, November 09, 2009 3:51 AM
>>> Subject: Re: [Amps] B- questions
>>>
>>>
>>>> ORIGINAL MESSAGE:
>>>>
>>>> On Sun, 08 Nov 2009 22:35:36 -0500, Roger <sub1@rogerhalstead.com>
>>>> wrote:
>>>>
>>>>> (I really dislike the term anti parallel...which logically
>>>>>means series, but is used to mean "parallel diodes of opposing
>>>>>polarity"
>>>>>and requires a expanded definition)
>>>>
>>>> REPLY:
>>>>
>>>> I don't like the term "anti-parallel" either, but it is an ancient
>>>> term
>>>> going
>>>> way back, and it is quite clear once defined. I'm open to suggestions
>>>> for
>>>> something better.
>>>>
>>>> To me, the logical opposite of parallel is non-parallel, but to each
>>>> his
>>>> own.
>>>>
>>>> 73, Bill W6WRT
>>>> _______________________________________________
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>>>> Amps@contesting.com
>>>> http://lists.contesting.com/mailman/listinfo/amps
>>>
>>> _______________________________________________
>>> Amps mailing list
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>>> http://lists.contesting.com/mailman/listinfo/amps
>>
>>
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>>
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>
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