NorthStar Horizon Case Cover Replacements

[Allison]

>
>Subject: RE: NorthStar Horizon Case Cover Replacements
>   From: "Chuck Guzis" <cclist at sydex.com>
>   Date: Wed, 20 Jun 2007 13:56:02 -0700
>     To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>On 20 Jun 2007 at 8:49, Allison wrote:
>
>> What made the box notable was floppies in the crate rather than external 
>> box and only a LED (power on) on the front pannel.  It was one of the early
>> turnkey systems and became popular with applications/system integrators 
>> for that reason.  The reason being it was now possible to sell a small(then)
>> system that was powerful enough to be a complete office accounting system.
>> It didn't hurt that the wood cover fit into office decor of the time. 
>> The wood disappeard when FCC started forcing RFI constraints.

By RFI I mean the kind of interferfence from the disgital switching action
that could blanket communications bands.


>There was a good reason for that.  A friend had purchased one of the 
>Integrand S-100 boxes with a floppy cutout.  He'd installed an SA-400 
>(IIRC) and complained that it wouldn't work reliably.  What I 
>discovered was that the field from the large power transformer was 
>playing hob with the drive electronics.  I installed a substantial 
>steel shield around the floppy and the problem abated.

NS* Horizon never had a transformer magnetic field problem. And the drives
are only a few inches from the transformer.

The problem may have been the CVC transfomer used in some Integrand boxes.
Those radiate a larger magnetic field.

>
>When I purchased my own Integrand box, I opted for the drive-less 
>model.
>
>Even on the Durango box, we had to shield both the drives and the 
>small monitor that sat over them to get reliable drive operation.
>

I have an NS* Advantage and they also apparently did it right as the drives
behave well without steel shield plates.

Allison


>Cheers,
>Chuck