Message-ID: <6364@brl-tgr.ARPA>
Date: Wed, 5-Dec-84 12:58:50 EST
Article-I.D.: brl-tgr.6364
Posted: Wed Dec  5 12:58:50 1984
Date-Received: Fri, 7-Dec-84 05:45:25 EST
Sender: news@brl-tgr.ARPA
Organization: Ballistic Research Lab
Lines: 58

First, the problems: The edge connector on the Teac drives is higher up
than on the Tandon and is 180 degrees reversed in position (upside down).
This is no problem if one has all Teac drives side-by-side but requires
a twist in the ribbon cable if Teacs are to be mounted next to a Tandon.
One COULD mount either the Tandon or the Teacs upside down but that
would be a bit confusing when putting diskettes in.  I would recommend
two or three or four Teacs in the Horizon.  If you have a need to
WRITE diskettes in "quad" format, one of the Teacs should be the 48-TPI
type.

There is no need to replace the ribbon cable.  Just crimp on one or two
more connectors, as required.

Some of my Teacs had mounting holes tapped for 3mm metric screws.  The
last units I bought had two sets of mounting holes, one set metric
and one set NF (US standard machine screws).  The metric-tapped holes
were centered, width-wise, on the drive and are recommended over the
other other holes which are offset considerably from the centerline.
Ask drive vendor to supply the 3mm mounting screws.  If you need to buy
them locally, try your local motorcycle dealer's parts counter.

The Teac drives are slightly longer than the Tandons.  It is necessary
therefore, to move two of the large filter capacitors back about one
inch and to move the rectifier back about 1/2 inch.  This is a simple
job of drilling a few holes.

If you elect to use four 1/2 hgt drives in the Horizon, some additional
metalwork is necessary as the bracket that supports the drives does
not extend far enough to the right side to support the right-most
drive.  I found that, by rotating the bracket 90 degrees and redrilling
it, it  would serve nicely.  I believe I have the drawing that I made
showing location of holes to be drilled.  I'll let you know if I am
able to find the drawing.  If you elect to use only three drives, place
them to the left and use a blank bezel to fill the right-hand gap.  I
had such an arrangement for a time and cut a full-hgt blank bezel in
half to make a 1/2 hgt bezel.

I can send you photos of my modified Horizon showing some of these details.
Need your US Snail address.

Power is no problem since the Teac drives use only 1/2 the current that
the Tandons require.  I simply paralleled a power connector to each
of the existing connectors and everything runs cool.  The photos will
show this detail also.  Will let you know later where to order the
connectors from.

About 95% of my oUUUUUUUUUUUUUUUUUUUUUUUAbout
95% of my old Verbatim diskettes format OK in the FD55F drives.  Some
of these are old ones rated for SD SS.  Recommend Brown No. 60-96-00
diskettes.  I've five boxes of these and NEVER had a disk go bad.  I
pay $39 a box for these.

Let me know if you decide to proceed as I may think of something else
that would be helpful.  Also, I can supply disk controller PROMs for
the Horizon DD disk controller, addressed at FC00 (top one-K) for
modest price.

				Al Plehn

Message-ID: <550@voder.UUCP>
Date: Fri, 7-Dec-84 12:25:12 EST
Article-I.D.: voder.550
Posted: Fri Dec  7 12:25:12 1984
Date-Received: Mon, 10-Dec-84 01:38:38 EST
References: <6364@brl-tgr.ARPA>
Organization: National Semiconductor, Santa Clara
Lines: 19

[bug food]

 >  Also, I can supply disk controller PROMs for
 >  the Horizon DD disk controller, addressed at FC00 (top one-K) for
 >  modest price.
 >  
 >  				Al Plehn

I would like to purchase a set of N* controller PROMs at FC00 for
a modest price.  What is the price and where should I send the check?
Thanks.

George B. Smith
National Semiconductor
...!{ihnp4!nsc | decvax!decwrl!nsc | ucbvax}!voder!gbs
-- 
George B. Smith
National Semiconductor
...!{ihnp4!nsc | decvax!decwrl!nsc | ucbvax}!voder!gbs