Alexandre intoned:
> DV-series notebook? :)
>
[...]
>
>----- Original Message -----
>From: "Scott Quinn" <saquinn624 at aol.com>
>To: <cctalk at classiccmp.org>
>Sent: Thursday, November 22, 2012 7:45 PM
>Subject: BGA resoldering - flux?
>
>
>I have a non-CC HP device
>[...]
Nope, HP LaserJet p20somethingorother printer. Controller board developed random
errors from time to time.
I have a non-CC HP device that has developed issues, probably because of a combination of the lead-free
transition and usual Chinese quality.
I'm planning on attempting a re-solder by reflowing in an oven (no hot-air rework station yet).
It seems as though it would be best to find some way to flux the balls to ensure that the
connection is good. I'm not removing the chip, so would a solution of rosin flux diluted in
alcohol and dripped onto the BGA work? Any better way, or is it unnecessary?
My plan was to ramp it up to 400F in an oven, soak for 5 mins, then cool down to minimize thermal
issues. Does this sound good?
I've recently restored a DEC TU58 dual-transport tape system but am
finding that 30+ year old DC100A cartridges are perhaps past the end of
their useful life.
The belts in many of them have rotted and broken.
There are still some places you can get new cartridges, but they are
more than $40 a piece.
Has anyone found a way to source and replace the broken belts?
I am not interested in preserving the data on the tapes as much as I
am interested in just having working tapes... so I don't get ahead by
moving a belt from a "good" cartridge to a bad one. I'm interested in
trying to repair the bad cartridges.
I've seen the writeup here, for the HP 9845 and its DC100As,
http://www.hp9845.net/9845/tutorials/savetapes/index.html
but that doesn't tell us what to do about broken belts other than to
steal them from other cartridges...
Chris
--
Chris Elmquist
On Fri, Nov 16, 2012 at 12:05 PM, Dave McGuire <mcguire at neurotica.com> wrote:
> On 11/16/2012 11:09 AM, Ethan Dicks wrote:
>> Nice. I have a couple of older Alphas (one is *much* larger, with a
>> Futurebus+), so I know a little about the line, but not the later
>> models. I had no idea HP packaged them up with their hot-swap drives.
>> I've only ever seen DEC-badged Alphas in person.
>
> What FB+ Alphas do you have?
One of these...
http://www.old-computers.com/museum/computer.asp?st=1&c=895
4000 AXP Model 710. Got it 10 years ago, fiddled with it when I first
got it (it boots to one of two different versions of UNIX on two of
the 5 installed SCSI disks) but don't have much reason to use it
often.
One interesting historical note - it was formerly OSCAR, the card
catalog computer for the Ohio State University library system. I
picked it up from surplus for $50 because I wanted the included TSZ07
(and I can't ship a TSZ07 for $50!) I put more hours on the tape
drive reading old backup tapes than I ever put on the server.
It has one CPU and about 1/4 the max amount of memory.
-ethan
I'm looking to help protect against frying my DUTs, oscilloscopes, logic
analyzers during testing.
I've been thinking about purchasing an isolation transformers, and I've
watched a couple video blog entries on the subject. [1]
While I'm pretty careful what I'm probing, I don't want an inadvertent
short of the test equipment ground to the positive supply rail off my
DUT to blow stuff up.
The strategy I intend on using is this:
1. Connect the primary side ground of the isolation transformer to
ground with a normal(US) 3-prong plug.
2. Float the DUT by using a 3-prong to 2-prong adapter when plugging
into the secondary side of the transformer.
3. Keep the o'scope or LA grounded with a normal 3-prong plug.
My DUT for the most part is a commodore amiga that has an external 120v
to +12v,-12v, and +5v power supply. I'm not intending on opening
supplies, troubleshooting/repairing them or generally touching anything
that has live mains power following through it.
The signals I'm probing are generally ground-referenced single-ended
signals.
Does this approach sound reasonable? I'm looking for practical
actionable advice. I'm looking at the BK1604A. [2]
Thanks,
Keith
[1] http://www.toddfun.com/2011/04/30/isolation_transformers/ and
http://www.youtube.com/watch?v=xaELqAo4kkQ (which is eevblog #279)
[2] http://www.tequipment.net/BK1604A.html#
Still getting used to Picasa, sorry. 2nd set of photos is
https://picasaweb.google.com/106111250846948401252/November21201203
Cindy Croxton
Electronics Plus
1613 Water Street
Kerrville, TX 78028
(830)792-3400 phone (830)792-3404 fax
AOL IM elcpls
_____
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2013.0.2793 / Virus Database: 2629/5908 - Release Date: 11/20/12
Rob writes:
> I've downloaded several ks10 instruction set diagnostics in .SAV file format from trailing-edge.com.
> In a 36-bit world, I think I understand the .SAV file format. I can't figure out the format that I've retrieved.
> I've even tried loading the .SAV files that I've retrieved into SIMH but SIMH complains about a "Format Error".
> Any clues? Did I mung the files copying them from the website?
I endeavored a little bit in the late 90's to get a modern FTP server that could move 36 bit executables intact. E.g. True 36-bit "BINARY" as per RFC 959, with the .SAV's arranged nibble-wise to work.
Failing at that, I even endeavored to get a RFC for 36-bit file movement via HTTP. Tried to drop hints to Marc Crispin (author of many RFC's).
But in the end I punted. What you want to do to get an intact .SAV, is grab the tape image and unpack the tape image on a PDP-10 (or emulated -10). The tape image is the primal object that will not get mangled.
Tim.
Just FYI:
http://www.robotrontechnik.de/html/forum/thwb/showtopic.php?threadid=4337
There are some Pictures of uVAXII processor boards, and pics of the east
German and the Russian uVAX Processors at thew end of that thread.
Regards,
Holm
--
Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe,
Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583
www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741
I've downloaded several ks10 instruction set diagnostics in .SAV file
format from trailing-edge.com.
In a 36-bit world, I think I understand the .SAV file format. I can't
figure out the format that I've retrieved.
I've even tried loading the .SAV files that I've retrieved into SIMH but
SIMH complains about a "Format Error".
Any clues? Did I mung the files copying them from the website?
Rob.
http://www.thecreatorsproject.com/blog/vintage-computer-symphony-plays-house
-of-the-rising-sun
Somebody has an awful lot of free time on their hands!
Cindy Croxton
Electronics Plus
1613 Water Street
Kerrville, TX 78028
(830)792-3400 phone (830)792-3404 fax
AOL IM elcpls
_____
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2013.0.2793 / Virus Database: 2629/5898 - Release Date: 11/16/12
