[Amps] construct ferrite "line isolator"

[Jim Thomson]

Date: Tue, 26 Oct 2010 09:47:55 -0700
From: Jim Brown <jim at audiosystemsgroup.com>
Subject: Re: [Amps] construct ferrite "line isolator"

On 10/26/2010 8:22 AM, Jim Thomson wrote:
> None of my audio rack gear has any Pin 1 problems.  It has to be some pretty old audio rack gear to have Pin 1 problems.

Nope. Most consumer and semi-pro audio and video  products, and 
virtually ALL ham and computer products have pin 1 problems at every 
audio input and output. The good news is that most PRO audio mfrs have 
gotten the word, and do not have pin 1 problems.

73, Jim K9YC

## By  'audio rack gear'    I meant  semi pro and pro audio, 19"  wide, rack mount audio gear. 
You can see all  14 x pieces of audio gear, split between 2  x Hammond steel cab's, on the 1st of 4 x pix
on my qrz.com page.    I use another 3 x pieces of 19" gear  for the tv / stereo upstairs. None of it has Pin 1 
problems.  I wouldn't buy any Pro-audio gear with Pin-1 problems.  I also made up all my own cables..using
shielded [braided]  cables..and neutrik XLR connectors.  There is enough room inside a XLR connector to install
500 pf  @ 25V , ceramic bypass caps. Tip to grnd..and ring to grnd...and both ends of each cable.  I matched
 em all up with my LCR meter before installing. No ferrite used anywhere,  Zero RFI problems.  The 
XLR inputs of all the rack gear have built in RFI suppression anyway.  All the Aphex gear also has RFI
suppression on the 120 vac inputs.    All the gear plugs into the same 120 vac, rack mounted power strips,the
power strips are rack mounted to the rear of the 2 x cabinets, daisy chained together.  That power bar mess
all plugs into one big  PI filter, then into the 120 vac.  

Jim  VE7RF