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-----Original Message-----
From: gudguyham <gudguyham@aol.com>
To: dezrat <dezrat@outlook.com>
Sent: Tue, Nov 29, 2016 06:36 AM
Subject: Re: [Amps] 8877 Grid Connection DC or Not
<div id="AOLMsgPart_2_31e53d49-b8f3-4ab6-a1cf-7e9619dd0eba">
<div class="aolReplacedBody">Jim, I use the same scheme as the Ameritron
AL-1500. Easy and very effective. Schematic is on their website for the
AL-1500. Don't forget a grid trip overload protection.
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-----Original Message-----
From: Bill Turner <<a href="mailto:dezrat@outlook.com";>dezrat@outlook.com</a>>
To: Amps group <<a href="mailto:amps@contesting.com";>amps@contesting.com</a>>
Sent: Tue, Nov 29, 2016 06:30 AM
Subject: Re: [Amps] 8877 Grid Connection DC or Not
------------ ORIGINAL MESSAGE ------------(may be snipped)
On Mon, 28 Nov 2016 21:00:21 -0600, you wrote:
>Has anyone run the grid of an 8877 not connected to ground as far as DC is
>concerned?
>
>I really need to meter the grid current by bypassing the grid to ground with
>capacitors and several 10 ohm resistors in order to meter grid current.
>Metering grid current by the CT of the filament transformer, and the – of the
>power supply cant be done. Because the power supply – is directly grounded.
>
>Anyone had luck doing this?
>
>Thanks 73
>Jim W7RY
REPLY:
You might consider un-grounding the power supply if you can. It's not
a safety issue - the difference between true ground and B- is a volt
or two at most. That allows you to use the conventional grid meter
between ground and B-. Trying to "ground" the grid with capacitors
can lead to unwanted resonances and instability as you probably know.
73, Bill W6WRT
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