[QuadList] was Saturday Quad Matinee feature..now magnetic scratches

[Steve White]

Guy,

Any relation to Bill Spiller, first GM at WCVE-TV?

Steve


On 11/19/12 12:55 PM, Guy Spiller wrote:
>
> My experience was that the front side master erase head also 
> contributed to this magnetic scratching problem.  It would develop 
> little pits in which the magnetized tape particles would embed 
> themselves with the same sad results.
> If I remember correctly, the service manual recommends cleaning those 
> tiny holes out with a small wire from time to time.  Always seemed a 
> little "iffy" to me to do, but I guess a thin soft copper wire wasn't 
> going to scratch whatever hard metal that post was made out of.
> The elimination of the air guide post with a roller guide, a la 
> Ampex,  and back-side master erase head on the 70C sure seems to help 
> that issue...at least from what I've observed since having them.
> Guy
>
> On 11/18/2012 12:33 PM, J. Mitch Hopper wrote:
>>
>> That's exactly what they were!
>> Worked with TR60/61/70a,b - all had the same trouble!
>> I used a small vacuum cleaner with a small rubber snout to suck out 
>> the holes.  The only trouble was having a good master ruined to be 
>> the signal that it was time to get out the hoover! ha ha
>>
>>
>> J. Mitch Hopper
>> Custom Video Systems Co.
>> Rochester, IL
>> 217-498-8438
>> id at brainmist.com
>>
>> It's been lovely but I have to scream now.
>>
>> ----- Original Message ----- From: <bill.spencer at northstarstudios.tv>
>> To: <Steve.White at 800CallNow.com>; <quadlist at quadvideotapegroup.com>
>> Sent: Sunday, November 18, 2012 9:37 AM
>> Subject: Re: [QuadList] Saturday Quad Matinee feature--KCOP, 13,Los 
>> Angeles--1979 Rose Parade remote truck "Behind the Scenes" withDavid 
>> Crosthwait
>>
>>
>>>
>>> Steve,
>>>
>>> Those are 'magnetic' scratches.  They were more prevalent on RCA
>>> machines because of a guide that had little holes in it with air 
>>> blowing
>>> through them to keep the tape from sticking.  Usually that guide got 
>>> the
>>> holes filled with magnetized debris that shed from the tapes and it was
>>> enough concentrated magnetism to erase small portions of the record
>>> passing by.  They stay in the same place because a small line of
>>> magnetism gets segmented by the quad heads rotation and shows up as a
>>> pattern diagonally from top left to bottom right.  At least this is 
>>> what
>>> someone told me about 50 years ago!
>>>
>>> Bill Spencer
>>> RF Engineering Supervisor
>>>
>>> 3201 Dickerson Pike
>>> Nashville, TN 37207
>>> Phone: 615-650-6000 x6610
>>> Cell: 615-445-5616
>>> Web Site: www.NorthStarStudios.TV
>>>
>
>
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