[sebhc] H89 BOOT SUCCESS

[Bill Beech (NJ7P)]

Alignment disks are nice, but a distribution disk can be used in place 
of it with the scope to test alignment.  The trick is still to maximize 
the signal on the low and high tracks of the disk from a place on the 
drive before they "slice" the signal.  Usually I try to put the scope on 
the output of the head amplifier before the signal gets into any digital 
devices.

I have aligned 5 and 8-inch floppy drives with both a standard alignment 
disk and a single-density distribution disk with success.  Learned these 
tricks when I was in Korea where nothing like that was available.

Bill

Barry Watzman wrote:

>Yes, but you would need an oscilloscope and an analog alignment disk (almost
>impossible to come by these days), or a digital alignment disk and a
>software program to utilize it and analyze the result (and while a digital
>disk will tell what the story is, it won't allow you to fix it, at least not
>easily).
>
>
>-----Original Message-----
>From: sebhc-bounces at sebhc.org [mailto:sebhc-bounces at sebhc.org] On Behalf Of
>Carroll Waddell
>Sent: Wednesday, May 16, 2007 18:05 PM
>To: sebhc at sebhc.org
>Subject: Re: [sebhc] H89 BOOT SUCCESS
>
>Barry Watzman wrote:
>
>  
>
>>The problem may be marginal alignment.  Also, as noted earlier, some drives
>>don't like being in an H89 right next to the deflection yoke (that's why
>>    
>>
>the
>  
>
>>mu-metal shield was part of the design).
>>
>>
>>-----Original Message-----
>>From: sebhc-bounces at sebhc.org [mailto:sebhc-bounces at sebhc.org] On Behalf Of
>>Carroll Waddell
>>Sent: Wednesday, May 16, 2007 15:59 PM
>>To: sebhc at sebhc.org
>>Subject: [sebhc] H89 BOOT SUCCESS
>>
>>Thanks to everyone in the group that gave me tips on my H89 boot 
>>problem. I just got it to boot successfully. The problem turned out to 
>>be 2, not one, but 2 bad diskette drives.
>>I used them on the H8 and they worked, so I moved them to the H89 and it 
>>wouldn't boot. I finally put them back on the H8, and they wouldn't boot 
>>there either.
>>When I tried other diskette drives I had, SWEET BOOT SUCCESS!  FOR THE 
>>FIRST TIME SINCE I BOUGHT THIS MACHINE!
>>
>>Carroll
>>--
>>Delivered by the SEBHC Mailing List
>>
>>
>>--
>>Delivered by the SEBHC Mailing List
>>
>> 
>>
>>    
>>
>Is there any way I can check the head alignment? I used to do head 
>alignment on large mainframe disk drives.
>Carroll
>--
>Delivered by the SEBHC Mailing List
>
>
>--
>Delivered by the SEBHC Mailing List
>
>
>  
>

--
Delivered by the SEBHC Mailing List