> From: Robert Ferguson <rob at bitscience.ca>
> Subject: Commodore Superpet video problem -- ideas?
> To: cctech at classiccmp.org
> Date: Thursday, January 31, 2013, 3:07 PM
>
> Hi folks,
>
> I'm having intermittent problems with my Superpet. It will
> run fine for some time, but then will "glitch" for a couple
> of seconds (including video distortion), and then hang.
>
> Having done a bit of digging, I suspect that the flyback
> transformer is arcing internally. The video board is the one
> in this schematic (http://zimmers.net/anonftp/pub/cbm/s...032/321448.gif).
>
> I can hear the arcing sound from area of the transformer
> when the glitch occurs, and I see no obvious external
> indications of anything sparking or shorting. I have looked
> at the voltages at the various test points noted on the
> video board schematic during normal operation, and they all
> appear OK.
>
<TEXT CUT>
>
> Thanks for any help anyone can provide.
>
> Rob Ferguson
>
>
I would say to use an oscilloscope to monitor the circuit *driving* the flyback transformer. I had an issue on a Compucolor II where this signal would periodically glitch, which changed the frequency, and cause the flyback to over-voltage and spark every time. The signal would glitch whether the flyback was plugged in or not.
Regarding microvax parts, you can have whatever you want. Just telll me where it is precisely, with line drawings if. Necessary. I know absolutely nuthink about DEC.
------------------------------
On Fri, Feb 1, 2013 8:04 PM PST Jerry Wright wrote:
>
>
>
>
>----- Original Message ----
>From: Chris Tofu <rampaginggreenhulk at yahoo.com>
>To: cctalk at classiccmp.org
>Sent: Thu, January 31, 2013 11:22:59 PM
>Subject: Re: Intel 310 computer case.
>
>
>Multibus box - I'll take it. Ships to 08005 probably.
>
>Chris this is real bare. has a limited Multibus back plane.
>No much bigger than a PC. no Power supply. I might have
>larger Mulibus box here if that would be better. ???
>
>I see your other reply. The M7555 is the disk controller
>for the Microvax. You should see the number on the
>colored pull. It has a large ribbon cable connection
>on the outward end.
>
>- Jerry
>
>------------------------------
>On Thu, Jan 31, 2013 10:42 PM PST Jerry Wright wrote:
>
>>I have a good empty case. any one need one ??
>>
>>Free + shipping
>>
>>- Jerry
Jerry - I WANT THAT BOX.LOL LOL LOL
In German - Der friggin boxen must becomen meinen
If you'll send it to.me, I'll take it. I don't know what else you have . Perhaps that is also of interest.
Where are you located? And please don't get offended at my humor. I'm a sick man...
------------------------------
On Fri, Feb 1, 2013 8:04 PM PST Jerry Wright wrote:
Me
>
>
>
>
>----- Original Message ----
>From: Chris Tofu <rampaginggreenhulk at yahoo.com>
>To: cctalk at classiccmp.org
>Sent: Thu, January 31, 2013 11:22:59 PM
>Subject: Re: Intel 310 computer case.
>
>
>Multibus box - I'll take it. Ships to 08005 probably.
>
>Chris this is real bare. has a limited Multibus back plane.
>No much bigger than a PC. no Power supply. I might have
>larger Mulibus box here if that would be better. ???
>
>I see your other reply. The M7555 is the disk controller
>for the Microvax. You should see the number on the
>colored pull. It has a large ribbon cable connection
>on the outward end.
>
>- Jerry
>
>------------------------------
>On Thu, Jan 31, 2013 10:42 PM PST Jerry Wright wrote:
>
>>I have a good empty case. any one need one ??
>>
>>Free + shipping
>>
>>- Jerry
Multibus box - I'll take it. Ships to 08005 probably.
------------------------------
On Thu, Jan 31, 2013 10:42 PM PST Jerry Wright wrote:
>I have a good empty case. any one need one ??
>
>Free + shipping
>
>- Jerry
------------------------------
On Wed, Jan 30, 2013 10:34 AM PST Stefan Skoglund wrote:
>Considering how badly google translates german to swedish, I THINK NOT
>!
Yeah. Im going to begin informally studying German soon. I have a Swedish cd too. Ill never forget how to say fish in Swedish. This much I can tell you. Lathe in German is drehbank I think. Watch maker is uhrmacher. I love German machinery.
Anyone have a stash of either card. Have a few
micro vax machines that are missing the M7555
and I need a couple of the M8061's for my micro
PDP11's
Also could use a 7140 Power supply or boards.
seems like every few years one of my 11/24or44's
machines has PS problems.
Thanks, Jerry
HP 3.5 discs I wonder if in the HP 150 manual?
Back when we sold the things .... I still have a maint manual for the
150... offlist mail me if you still have questions and I will dig it up.
Ed Sharpe archivist for SMECC www.smecc.org
In a message dated 2/1/2013 10:25:55 A.M. Mountain Standard Time,
cctalk-request at classiccmp.org writes:
Message: 5
Date: Thu, 31 Jan 2013 21:50:14 +0000 (GMT)
From: ard at p850ug1.demon.co.uk (Tony Duell)
To: cctalk at classiccmp.org
Subject: Re: Looking for Appendix to HP 3.5" disc drive service manual
(disc commands)
Message-ID: <m1U121T-000J4cC at p850ug1>
Content-Type: text/plain
> I was interested to read about the differences between the 9121 and
> 82901 commands, eg the 9121 supports a superset of the 82901 commands
> and so should be fully backwards compatible. One difference I have noted
I beleive it was specifically designed to be. It was intended that any
systme that supported the 82901 could also use the 9121, no matter waht
assumptions it made. In this repsect, the respose to the standard
idenmtification coammends is the same, there is one extended command that
returns a differnet value o nthe 2 drives so it is possible to tell them
apart, but a ssytsem designed fo the 82901 wouldn't use that command.
Also the total numebr of sectors per disk is the same -- IIRC the 82901
is double-sided 35 cylidner and the 9121 is single sided 70 cylinder.
-tony
------------------------------
On Thu, Jan 31, 2013 10:38 PM PST Jerry Wright wrote:
>Anyone have a stash of either card. Have a few
>micro vax machines that are missing the M7555
>and I need a couple of the M8061's for my micro
>PDP11's
>
>Also could use a 7140 Power supply or boards.
>seems like every few years one of my 11/24or44's
>machines has PS problems.
>
>
> Thanks, Jerry
>
I don't have a clue what you're looking for, but I have a MVax parts machine. Maybe that has what you're looking for...
On Feb 1, 2013, at 12:00 PM, cctalk-request at classiccmp.org wrote:
> From: Pete Turnbull <pete at dunnington.plus.com>
> To: General Discussion: On-Topic and Off-Topic Posts
> <cctalk at classiccmp.org>
> Subject: Re:
> Message-ID: <510AD86B.8020007 at dunnington.plus.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> On 31/01/2013 05:37, Charles wrote:
>> Anyhow, I figure that the OS/8 pack might have become corrupted, so I
>> attempted to reload it on my 11/23+ system (which IS working and
>> passing
>> memory tests) using VTserver, which is how I created it the first
>> time.
>> However, since I last successfully did it, I've upgraded the 11/23+
>> boot
>> ROMs to the KDF11B-BH V1.0. This is the only hardware change. Not
>> sure
>> if that has anything to do with the problem
>
>> Do I need to go back to the original boot ROM in order to use
>> VTserver
>> (i.e. is there some change made to ODT that is messing things up?)
>
> The boot ROMs have no bearing on ODT, which is in the microcode in the
> KDF11 itself. So you can eliminate at least one area of concern.
> What
> boot ROMs did you have before? Were they 2K ones (11/23+) or 8K ones
> (microPDP-11/23)? Have you changed any jumpers during the upgrade?
>
> --
> Pete
The original ones (-339, -340) are 2716 EPROMs (2k). The only jumper
changed was the J23-24 which the manual says to set for 8K proms, and
J23-22 for 2k.
I put the old ones back in (and set the jumper accordingly) and the
transfer proceeded normally. For whatever reason the new ones do not
like VTserver.
Incidentally, the problem with the 8/A & RL02 turned out to be simply
a bad ribbon cable connection (my fault) where the IDC connector plugs
into the RL8A card.
The previous OS/8 pack boots and runs normally too... now I can get
back to playing Lunar Lander in FOCAL on the Teletype, and ADVENT :)
-Charles
Steven Hirsch <snhirsch at gmail.com> wrote ..
> On Wed, 30 Jan 2013, mc68010 wrote:
>
> > I can't believe how crazy the Apple thing has got. One of Sellam's Apple II
> > just sold for almost $4k. Wow.
>
> Rev. 0 Apple ][s with low serial numbers are being sought after. Another
> unit went for > $5k the other week, but the buyer apparently reneged. If
> that was one of Sellam's, it's all the more ammunition for his legal
> action.
>
> I can accept that there may be cases where a landlord can auction items
> left on premises under a default, but I'm not aware of any situation where
> they are allowed to blindly profit from the action.
>
> Steve
>
>
> --
It's not just an Apple thing. A TI-99/8 just went for $3240 on Ebay. It seems this was the second one over $3000 in the last 6 mos., so apparently it's not a fluke. Prices on vintage stuff generally seem to be on an up-cycle, apparently unlike the value of the time and labor spent assembling and protecting collections of historical, cultural, or economic significance. Tell it to the vandals in Timbuktu, maybe.
I'm just catching up on the list after being too busy to read it the last couple of months, and I'm still digesting Sellam's situation. Been through some similar circumstances, myself, and on the other hand, I do some work for an asset management co. that handles a lot of rentals, and to my intense dislike, property left behind after sadly , no matter what you do, with owners breathing down your neck, the inevitable evictions, property we go out of the way to have the tenant come get. But they don't. Much less pay the back rent. So maybe I have a somewhat unique perspective on the matter. I'm not sure, however, that I could remain either temperate or coherent about it, so I'm going to refrain from comment just now. I can tell, though, when failure to pay rent on a timely basis is a thinly veiled pretext for theft. Good luck, Sellam.
jbdigriz
>
> I'm having intermittent problems with my Superpet. It will run fine for some
> time, but then will "glitch" for a couple of seconds (including video
> distortion), and then hang.
>
> Having done a bit of digging, I suspect that the flyback transformer is
> arcing internally. The video board is the one in this schematic
> (http://zimmers.net/anonftp/pub/cbm/s...032/321448.gif).
>
The link is mangled. I think it should be:
http://zimmers.net/anonftp/pub/cbm/schematics/computers/pet/8032/321448.gif
>
> I can hear the arcing sound from area of the transformer when the glitch
> occurs, and I see no obvious external indications of anything sparking or
> shorting. I have looked at the voltages at the various test points noted
> on the video board schematic during normal operation, and they all appear OK.
>
> I'm sort of stuck at this point. Should I replace the flyback? The part
> number is 2432641AL 25M, and it's T721 on the board; does anyone know of
> an available equivalent?
>
I'm not familiar with the the Superpet but I have had similar faults in other
equipment which were caused by failed joints on the PCB. If the problem
happens reasonably frequently, one approach is to darken the room and watch
the underside of the PCB for little sparks. If it doesn't happen that
frequently, another approach is to try tapping the PCB at various points with
a well insulated implement such as a plastic ruler or other tool to see if the
fault can be mechanically provoked.
Do not overlook the possibility of arcing at the EHT connector on the CRT or
on the CRT base.
I would hate to end up replacing a major component and finding that the
problem was still there.
>
> Alternatively, could this behaviour be caused by a bad electrolytic
> capacitor? I'm specifically suspicious of C754 (47uF/250V), but my knowledge
> of CRT theory is not deep, and I lack a good way to test the capacitor in
> circuit.
>
It's not the sort of thing I'd suspect an electrolytic capacitor of but I
suppose it is possible. Usually when they are stressed enough to make noise,
there are visible signs of stress too.
An oscilloscope connected between its negative terminal and ground it would
probably show a significant increase in ripple or reduction in voltage when
the problem happens if the capacitor is at fault.
Regards,
Peter Coghlan.
Hi folks,
I'm having intermittent problems with my Superpet. It will run fine for some time, but then will "glitch" for a couple of seconds (including video distortion), and then hang.
Having done a bit of digging, I suspect that the flyback transformer is arcing internally. The video board is the one in this schematic (http://zimmers.net/anonftp/pub/cbm/s...032/321448.gif).
I can hear the arcing sound from area of the transformer when the glitch occurs, and I see no obvious external indications of anything sparking or shorting. I have looked at the voltages at the various test points noted on the video board schematic during normal operation, and they all appear OK.
I'm sort of stuck at this point. Should I replace the flyback? The part number is 2432641AL 25M, and it's T721 on the board; does anyone know of an available equivalent?
Alternatively, could this behaviour be caused by a bad electrolytic capacitor? I'm specifically suspicious of C754 (47uF/250V), but my knowledge of CRT theory is not deep, and I lack a good way to test the capacitor in circuit.
Thanks for any help anyone can provide.
Rob Ferguson
On Wed, Jan 30, 2013, Glen Slick wrote:
> Not the exact manual you were looking for but might have the same
> information. This scanned copy includes pages Appendix A-1 through
> A-36.
> http://bitsavers.trailing-edge.com/pdf/hp/disc/5957-6584_9123D_3.5_Flex_Dis…
Thanks Glen that's great, must have been a few minor corrections to Appendix A in this update to the original service manual.
I was interested to read about the differences between the 9121 and 82901 commands, eg the 9121 supports a superset of the 82901 commands and so should be fully backwards compatible. One difference I have noted is using HPdir the 9121 appears to faster than the 82901, in that on a fast PC HPdir has to be slowed down to work successfully with the 82901 (eg by enabling logging) and works fine with the 9121, and on a slow PC both drives work fine with no attempts to further slow down the program. I've fed this back to the program author for further analysis.
I can try and dump the drive firmware if anyone is interested in doing a detailed comparison.
Regards,
John
A frustrating evening in vintage computer-land, as you will see. Also
the drive belt popped off my 33ASR during the fun. And Windows
Networking to the old PC I use to run VTserver was initially
nonfunctional as usual, but I digress.
I fired up my PDP-8/A after a long hiatus, and it won't boot OS/8 any
more (on boot, the RL02 immediately flashes its Fault light briefly
but then becomes ready again, and the system halts). The drive seems
to be working without errors at least according to the short test
programs from the user's guide I keyed in - I don't have a diagnostic
pack - but reading the status register shows no error bits set, and
the Oscillating Seek program also runs properly...
Anyhow, I figure that the OS/8 pack might have become corrupted, so I
attempted to reload it on my 11/23+ system (which IS working and
passing memory tests) using VTserver, which is how I created it the
first time.
However, since I last successfully did it, I've upgraded the 11/23+
boot ROMs to the KDF11B-BH V1.0. This is the only hardware change. Not
sure if that has anything to do with the problem, which is:
When attempting to download the disk image, the copy portion of the
program loads (starting at 140000) but won't execute, halting at
140002. I discovered that I had the Halt switch set. If the Halt
switch is NOT set, when execution is supposed to begin, instead the
11/23+ says "ERR 4 MMU ABORT" and also won't accept the incoming disk
image data!
Do I need to go back to the original boot ROM in order to use VTserver
(i.e. is there some change made to ODT that is messing things up?)
Also, does anyone have a paper tape version of the RL02 diagnostics
for PDP-8?
thanks
Charles
Glen & Christain, many thanks for the information, and the pointer to the 9895A service manual at http://www.hpmuseum.net/exhibit.php?hwdoc=262The manual also has this to say:
p.37:Before reading or writing a sector of data, the controller must position the read /write head of the disc drive over the desired sector. To do this, the controller sends signals to the disc drive to step the head to the desired track. The controller then begins to read the disc. Track and sector information is stored as a preamble to each sector, and the disc is formatted in a manner to allow the controller to detect the beginning of a preamble. On finding a preamble, the Z80A first checks that the track number is correct. If not, it will continue to step the head until the correct track is found.
p.43 has figure 2-3 Track Format.
This shows each sector consists of (ignoring gaps):ID Field made up of:- Sync up Bytes- Address Mark (AM) [in other manuals refered to as IDAM]- ID Information (bytes indicating the logical track, head and sector address)- CRCData field made up of:- Sync up bytes- Address mark [in other manuals known as Data Address Mark or DAM]- Data- CRC
p.45 Address MarksID AM : Data pattern = !70Defective Track AM : Data pattern = !F0
At the command set level, a clear D bit indicates an ID AM in the ID field, and a set D bit indicates a defective track AM in the ID field.
p.86 Start of Appendix A, 9895A Disc Memory Command Set
p.89 - has description of the D bit.
p.95 Shows the Command Table.
p.105 'Request Logical Address' Purpose: The 9895A returns bytes indicating the current target address. This command is used to determine the address of the offending sector after a data error has occurred.
p.106 'Request Physical Address'.Purpose: The 9895A returns bytes indicating the physical cylinder on which the head actuator is positioned. This is useful for calculating the number of invisible tracks between the outer-most track and the current track. This is done by subtracting the physical cylinder address from the target cylinder address.
P1.31 Describes the Initialize command, and P.133 the Format command. Together these sections describe use of the D but and invisible tracks.
To conclude, information such as the IDAM content won't be readable by a PC with a normal FDC, so this approach looks limited. I am in touch with Ansgar reading his wonderful hpdir project, which I am using with my Series 80 disks on an 82901M drive, so will point him here for a bit more light reading ;-)
Regards,John
Hi!
Is there any German speaking builder who would be willing to translate an
article for a well-known European hobbyist electronics magazine? (You'll
recognize the magazine but I'd rather not post that here for privacy
concerns)
One of the N8VEM builders, Oscar, has written a great article in English on
the N8VEM project. We have interest from the magazine but of course they
want the article in German.
Would someone who is proficient in German please volunteer to help us out?
Thank you very much in advance! I appreciate your support!
Have a nice day!
Andrew Lynch
Item # 160965266758
>From the listing:
Part # 21-370, 8-7/16" X 370' of 16# bond paper, 1" cardboard core, 12 rolls per case, 99 cases available
$30 per case, quoted $20 shipping to my location in California
No connected with the seller, other than ordering a few.
--Bill
http://northtech.us/content/20130123/end-era-rip-fafner
I only got to use it a few times, but it was nice to be able to
connect to some real iron (I still have an account on the LCM's
11/785, I think). Service is continued on an Alpha DS20, but
my username seems to be a bit broken at the moment.
Many thanks to Dr. Ulmann for running such a majestic machine
at considerable personal expense for all to use!
- Dave
Why not just put it in a web documwnt and let google do it? Most of it...
------------------------------
On Tue, Jan 29, 2013 3:55 PM PST Andrew Lynch wrote:
>Hi!
>
>
>
>Is there any German speaking builder who would be willing to translate an
>article for a well-known European hobbyist electronics magazine? (You'll
>recognize the magazine but I'd rather not post that here for privacy
>concerns)
>
>
>
>One of the N8VEM builders, Oscar, has written a great article in English on
>the N8VEM project. We have interest from the magazine but of course they
>want the article in German.
>
>
>
>Would someone who is proficient in German please volunteer to help us out?
>Thank you very much in advance! I appreciate your support!
>
>
>
>Have a nice day!
>
>
>Andrew Lynch
>