The reason for no daisy chain is that some piece of equipment will be moved
and the link broken and not fixed and some gear is left ungrounded. Most
manufacturers want you to run separate ground wires to a common ground BUSS
which is connected to the power line ground.
Walt k8cv Royal Oak, MI.
--------------------------------------------------
From: "Richards " <JRUING@AMERITECH.NET>
Sent: Thursday, November 26, 2009 12:57 AM
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Subject: Re: [TenTec] humm
> Hi Jim -- I am fascinated by you comments because
> I believe they are accurate. And, yet, TenTec told
> me not to daisy chain the chassis grounds together
> and their 963 power supply has no ground lug at all.
> AND... my station has no humm, or other adverse
> audio issues.
>
> So... are these things all bonded to their respective
> chassis internally already... or is the daisy chain
> ground lug theory something else... or what? Other
> than some lightning protection on the antennas, I have
> no other ground other than the third prong on the power
> cords.
>
> (I do pay attention to how I wire up the microphones...
> and have no problems with that... but I must confess
> I am STILL trying to understand all the nuances of that
> "pin 1 problem" you audio engineers keep harping on.)
>
> In this regard, I recall a nice discussion with Bob K4TAX
> about grounding the power supply - and I believe that
> discussion overlaps this one - and we then discussed
> how TenTec gave me different advice (not trying to
> rehash it... just referring to it.)
>
> Oh, well, maybe ANOTHER read of all those reference
> articles will clue me in.
>
> ========== Richards -K8JHR ================
>
>
>
> On 26 Nov 2009 at 7:53, Jim Brown K9YC wrote:
>
> Not bonding the negative terminal to the chassis creates a
>> pin 1 problem, and is likely to CAUSE damage to the supply. Study
>> the material on "the pin 1 problem" on my website.
>>
>> ALL equipment chassis MUST be bonded together, AND to the antenna
>> shields, AND to the power system ground, AND to the Telco and CATV
>> cables and their grounds. It is when those bonds are missing that
>> damage is more likely to occur.
>
> ===============================================
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