test-drb December 1999

test-drb@ccmp.vtda.org

186 participants
742 discussions

by dylanb＠sympatico.ca

-----Original Message----- From: Christian Fandt <cfandt(a)netsync.net> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Sunday, December 05, 1999 10:30 PM Subject: Re: Tube experts! - I T WORKS! >Upon the date 02:16 PM 12/5/99 -0500, John B said something like: >> >> >> >>-----Original Message----- >>From: Allison J Parent <allisonp(a)world.std.com> > -- snip -- >>>???? Why? The scope is an enclosed system that would be hard pressed to >>>emit high voltages back into the system it's hooked to. It's not like the >>>HP9100 in that respect. For the RM503 to do that the HV lead would have to >>>fall on one of the input lines! As I remember the series 8 Display scopes >>>were driven off a pair of D/As and some single bit output to blank the >>>beam. If you have something different I'd like to hear about that. > >I agree with Allison. Without knowing exactly the mods done by DEC that you >mention below, I'm still assuming the output of the D/As is connected right >into the SO-239 style front panel input connectors. In that case, the input >circuitry is isolated from any HV. The inputs go directly to the vertical >and horizontal amplifier tube grids (the 6DJ8's) after passing thru their >respective attenuator switch assemblies. > They did not hook up to the front panel inputs. They used 3 connectors on the back of the scope (x,y,z). All went into the amplifiers (except for Z of course). >> >>Three D/As. 1 12 bit for x, 1 12 bit for y, and 1 3 bit for intensity. When >>the transformer went in this RM503 it raised the regular voltages throughout >>the scope to 500+ volts... in some places over 1000. That was present right > >Ouch. I hope bypass capacitors and some coupling caps haven't had their >dielectric damaged. Most of the ceramic caps and poly caps have ratings of >500 and 600 volts DC respectively and 1KV is pushing or exceeding their >surge voltage rating. > No, I tested it for very short times. I don't bother cycling power when I see stuff like that. >>through to the input. I am protecting the D/A converters as I don't need the >>PDPs taking major beatings in the future. All the supplies inside the scope >>(-100,100,250,85,-3000 were going nuts). The other RM503 I have has the same >>problem. I am going to put an isolation transformer on every RM503,RM560 >>scope I get to solve the problem ahead of time. > >The other one has same problem? Interesting coincidence or possibly a >common failure mode of this scope. I *was* going to put a benchtop style >503 on my 'hunt for' list as it looks to be an excellent X-Y scope for my >bench but I'll do some further thinking on that I guess. > Yes it does. But don't worry... I like this 503 and with an isolation transformer inside that problem will never happen again. >> >>The 8 Display controllers have the intensity option :-) (for spacewars of >>course). The AX08 (XR option) and the 34D (standard) had a 3 bit intensity >>D/A output for the scope. The RM503s were modified by DEC for intensity >>control. > >That manual you said you have, is it from DEC or Tek? I'm curious about the Both, one from Tek and the LAB-8/34D interface manual from dec. >mods. If you have a vanilla Tek manual like I have you can see that there >are a pair of binding posts on the back of the unit which may be labeled >"CRT GRID" and "GND." The GRID connection goes directly to the CRT grid >through a 0.001 mfd capacitor. > >Now if DEC has done some fancy stuff to the 'scope by intrusively >interfacing the PDP8 display controller directly to the deflection >amplifier circuits in some manner then yes, I'd be leery of potential >damage to the PDP circuits. Same for the intensity modulation (aka Z-axis >modulation) circuit. > Yes they did... and I will do the same with some isolation added. This scope is surprisingly stable... I just finished building a flip chip tester and will be populating the 34D tonight... I hope it *lights* up. john http://www.pdp8.com/ >Regards, Chris >-- -- >Christian Fandt, Electronic/Electrical Historian >Jamestown, NY USA cfandt(a)netsync.net > Member of Antique Wireless Association > URL: http://www.antiquewireless.org/ >

25 years

Got the oscilloscope interface running on the 8/S!

by dylanb＠sympatico.ca

It's rather comical.. poor thing.. The 8/s wasn't exactly a super computer but it is having a little difficulty printing a line of 32 characters (5X7 bits). I can read the text but by the time it finishes drawing the end of the line, the first few characters start disappearing. I will try and post some pictures over the next couple of days. It is pretty cool to see this unit draw on an oscilloscope. I will try some video games (some were written for the 8/s) and post some pictures of that as well. john PDP-8 and other rare mini computers http://www.pdp8.com -----Original Message----- From: Mike Ford <mikeford(a)socal.rr.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Monday, December 06, 1999 4:09 AM Subject: Re: Tube experts! - I T WORKS! >>> The tube newsgroup recently has been talking about buying old scopes just >>> to harvest the tubes. When you get a good look at what good quality tubes >> >>Is it just me, or is this as distasteful as scrapping classic computers >>for gold? Old 'scopes have a perfectly good use already -- to display >>waveforms > >I have a Dumont 304a I tried to get $10 for without success. Pulling the >tubes will increase the value nicely. Its just like the 1130, if nobody is >willing to pay some premium over the value of the gold, then nobody wants >it very much. > > >

25 years

ebay feedback

by dylanb＠sympatico.ca

-----Original Message----- From: Innfogra(a)aol.com <Innfogra(a)aol.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Sunday, December 05, 1999 2:03 PM Subject: ebay feedback >In a message dated 12/5/1999 10:22:16 AM Pacific Standard Time, >rigdonj(a)intellistar.net writes: > >> > >> >Can you list negative feedback for a person even if you had no dealings >> >with them??? >> >No you can't anymore. If you detect or suspect fraud then anyone can report >that to Safe Harbor, the customer service department. I have done that, and >like keeping up with spares, if you have a good reason for suspicions you >should report it. > >The old adage still holds, "If it is too good to be true then it generally >isn't." Some frauds are easy to detect. > >The "IBM MF' guy is just stupid. I bet his item gets no bids. Stupid people >don't deserve a response. > >The DEC card in France. I don't think I would send cash up front to him. >However he could just be a low budget person, this may be just fine. Scrap >value on that card is about $8.00 in todays market. > David Winter (the guy in France) has bid on some of my items and always paid quickly. He seems to collect boards but does not buy entire systems. >I don't think any IBM 1130 is worth more than a couple of hundred in scrap by >the way. I suspect less than that. > Then I guess the scrappers will be outbidding you..... The larger 1960 mini computers had a lot more gold in them than the '70s models as the gold was plated thicker in the '60s. The 1130 (from what I can remember) has more than $100US in aluminum in it (just cpu + printer). I don't know what the gold content is.. (I'll find out.. I know a company that does).. BTW I just lost an IBM 360 to a gold scrapper [bid more than me]. Some of the metal scrappers I know never bothered to look at gold content.. what's scaring the hell out of me are these guys that know to the penny what they can extract out of it and generally bid a lot higher than most. john PDP-8 and other rare mini computers http://www.pdp8.com >Paxton >

25 years

Adopt a scrapper and paper tape punches.

by Innfogra＠aol.com

In a message dated 12/4/1999 10:05:36 PM Pacific Standard Time, mrdos(a)swbell.net writes: > would take it seriously. It's really not a bad idea, and I'm sure our fellow > collectors would go for it. We really need an organization to preserve old > computers. I go to scrap yards and see classic machines ripped apart all the > ti While I like the idea of an organization to preserve old computers I suspect there are already several. This list actually works well for rescues. The biggest problem is that the scrappers are rarely computer literate. If they are they are already selling on ebay and the Internet. Most scrappers are metals oriented. Even if they are recyclers the bottom line is the value of the metals. Volume is the problem, you must scrap or get buried in it. The best answer is to make friends with a scrapper. Anyone who will pay twice the scrap value consistently will be a welcome customer. In the long run you may get systems set aside for you to look at. Ask for particular brands or items but don't become a pest. They need to know what you are looking for. Check on a regular basis. Don't ask them to call you unless you are willing to offer significant money. They are busy and you are not a major part of their business. I bet there are enough people on the list to cover the major scrappers in each city. If each person adopted one we could flood this list with equipment. And probably dump enough on ebay to depress prices. I am adopting one here in Portland. And that brings up paper tape punches. He has a REMEX paper tape punch and reader set. It is shrink wrapped on a pallet and I have not had a chance to look at it yet. He wants $250 but may be open to offers. He sells a lot of stuff to Western Numerical Controls. They are old and extremely heavy, I would say late 70s but that is a guess. If anyone is interested please email me off the list. Paxton

25 years

Gold price was: Re: ebay feedback

by dylanb＠sympatico.ca

-----Original Message----- From: Christian Fandt <cfandt(a)netsync.net> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Sunday, December 05, 1999 9:07 PM Subject: Gold price was: Re: ebay feedback >Upon the date 01:07 PM 12/5/99 -0500, John B said something like: >> >> >> >>-----Original Message----- >>From: Innfogra(a)aol.com <Innfogra(a)aol.com> > > -- snip -- >>>I don't think any IBM 1130 is worth more than a couple of hundred in scrap >>by >>>the way. I suspect less than that. >>> >> >>Then I guess the scrappers will be outbidding you..... The larger 1960 mini >>computers had a lot more gold in them than the '70s models as the gold was >>plated thicker in the '60s. The 1130 (from what I can remember) has more >>than $100US in aluminum in it (just cpu + printer). I don't know what the >>gold content is.. (I'll find out.. I know a company that does).. BTW I just > >Gold was a lot cheaper per ounce back in those days compared to now even >when considering inflation. US$35 an ounce I think I recall in the late >60's/early 70's before it really shot up in price. Was up to US$700 or so >for a short time a couple of decades ago. Around US$300 per ounce now I >think. So it would be probable to find connectors, circuit card >connections, etc. with a heavier layer of gold on a 60's-vintage machine >like the 1130. Also, there was a whole *heap* more connections in such a >machine vs. the highly integrated mainframes/minis of rather recent times. >This gives a better perspective of what those scrappers will pay for a >machine. But $4K for an 1130 as John reported hearing still seems high. >Other really precious metals inside of it? Platinum? Goo-gobs of silver (at >about US$3 an ounce)? I thought he was out of his tree when he told me what he was paying for the mainframes. I didn't believe it until I saw a fax on a piece of equipment in the warehouse which showed he bid $8000 on an IBM 30 series mainframe (water cooled) THAT WAS ONLY THE CPU!. He had other bids on the other parts. He looks at each piece, puts a price on it and then totals it on the bottom. I believe he said the Hitachi supers used Platinum [not sure, he did mention one metal other than silver or gold). BTW: The sick &*^*&*(^ offered to buy the two Fujitsus I have coming in for a decent $$$ due to gold content. He also asked me if I was interested in selling any of my 1960's minis for gold as well. As I will probably be sending the Vax 6000 I get to him (hey! I can't pull minis out of him without sending some...), I will ask him to quote me on: Fujitsu Super computer (I'll list the items as I saw them on his fax). The Vax 6000/610 with drives, etc... An IBM360 and a PDP-8/S I want to know what kind of $$$ he is actually going to offer. I do get a lot of sites willing to accept $1-3K for *many systems* but I hate to compete with this kind of company without knowing what I should be offering. > >>lost an IBM 360 to a gold scrapper [bid more than me]. Some of the metal >>scrappers I know never bothered to look at gold content.. what's scaring the >>hell out of me are these guys that know to the penny what they can extract >>out of it and generally bid a lot higher than most. > >Sounds like they have a network or something in which they describe (or >boast about) what they've salvaged. > This guy did 13 million pounds last year. I am sure he knows how much $$$ in metal is in ever mini/mainframe/super computer on the planet.. He even knows the contents for Apple IIcs [don't laugh.. he had a skid full of them] and IBM PS/2 XXX series. john http://www.pdp8.com/ >Regards, Chris >-- -- >Christian Fandt, Electronic/Electrical Historian >Jamestown, NY USA cfandt(a)netsync.net > Member of Antique Wireless Association > URL: http://www.antiquewireless.org/ >

25 years

V4.7 and VMS vs MicroVMS

by CLASSICCMP＠trailing-edge.com

>I was going thru some drives and tapes yesterday while trying to >resurrect my MVII and came across a v4.7 distribution I din't know I >had. This leads me to ask, one, if the person looking for same a few >days back (Enrico?) found one. And a second, stupid question. Stupid >because most of you probably know the answer. But as a PDP11 type >relatively new to the VAXworld I'd like to know what is the >difference/Is there a difference between VMS, MicroVMS? The tape I found >is labeled MicroVMS v4.7 bin. In the late V4 days, there were two kinds of VMS distribution kits: "full VMS", as you would install on a 11/730, 11/750, or 11/780, or 8600, or..., and there was "MicroVMS", which is what you put on your Microvax I or II. "MicroVMS" distribution kits were on huge stacks of floppies (RX50 or RX33 depending on what flavor you needed) and TK50 carts. MicroVMS is a "trimmed-down" VMS distribution, with the parts that aren't necessary (like Big-VAX support) or aren't usable on a Microvax (like the RSX-compatibility mode stuff) taken out. -- Tim Shoppa Email: shoppa(a)trailing-edge.com Trailing Edge Technology WWW: http://www.trailing-edge.com/ 7328 Bradley Blvd Voice: 301-767-5917 Bethesda, MD, USA 20817 Fax: 301-767-5927

25 years

Clarification

by kyrrin＠bluefeathertech.com

Hi, Dave and the list, It occurred to me tonight that my comments to the list regarding the moron posting some old PC as a mainframe on E-bay could have been misinterpreted where AOL was concerned. When I mentioned that the guy's posting from an AOL address 'wasn't likely to help,' I was merely referring to the popular stereotype that many techies I've met seem to have regarding AOL users. This stereotype holds that most AOL users have no clue about how computers, or any type of electronics, do what they do, can barely find the power switch unassisted, and that they wouldn't know a mainframe from a toaster oven. My comments were in reference to the fact that anyone even the slightest bit hardware-literate would likely be suspicious of the auction because it was posted using an AOL contact address. Now, my own view is that this stereotype is a big bunch of meadow muffins. You are living proof of that. AOL may not be my provider of choice, but that doesn't mean that others will see it that way. I try not to make a judgment call one way or another until I've actually seen free-form questions or writings from the user in question. Translation: No offense meant. I was merely making an observation based on popular stereotypes. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner and head honcho, Blue Feather Technologies http://www.bluefeathertech.com // E-mail: kyrrin(a)bluefeathertech.com Amateur Radio: WD6EOS since Dec. '77 "Our science can only describe an object, event, or living thing in our own human terms. It cannot, in any way, define any of them..."

25 years

HP stuff

by donm＠cts.com

For the benefit of the various HP hunters, there will be an auction in San Diego on Saturday, Dec 11th at 10 AM. Site is at 9389 Dowdy Drive off Miramar Road. Inspection Thurs 2PM-8PM and Sat 8 AM until start of auction. Equipment is purportedly from Pacific Bell Concord CA facility. Over 30 HP 9000 controllers as well as Digital controllers and drives, Gandalf controllers ... Contact A-1 Auction Liquidators 858-689-2324 Voice 858-689-2334 Fax - don

25 years

Tube experts! - I T WORKS!

by dylanb＠sympatico.ca

-----Original Message----- From: Allison J Parent <allisonp(a)world.std.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Sunday, December 05, 1999 3:06 PM Subject: Re: Tube experts! - I T WORKS! ><Okay.. (my lack of tube knowledge talking)... a TV repair guy I know who us ><to do a lot of tube work told me tubes only last a couple of years. I did > >In TVs where the tubes are low end and not always run at their best >operating points that may be true. In Qualtity test equipment that is >rarely the case. > ><not want to have to recalibrate this scope everytime a tube drops out. Also ><I will be reselling quite a few of the tubescopes with PDP-8s and don't wan > >Mechanical shock and power cycling tends to ruin tubes faster. Generally >tubes have good lifetimes and can be considered reliable (excluding the >effects of heat on surrounding parts) . > ><the scopes going south a month after they get them. I've ordered the spare ><but first I'll see how long the scope will last with the ones it has now. > >Best to leave be unless there is a direct indication one may be soft. >Don't forget with the exception of open filements or shorts from mechanical >shock tubes tend to fail slowly and soft. > ><This one has 4 transistors in it. I am checking the caps right now. > >Good idea s those (caps) do fail. > ><>> The only reason I don't like tubes is because they are very flakey in ol ><>> mini computers.. From what I have heard from people who use to support ><them ><>> every power cycles was a nightmare. I am trying to stick to minis that > >That is true, usually they get filiment failures and those are easy to >spot. Power cycles tend to accelerate that. then again I had a tube >organ (some 80+ tubes) and only had one failure in 8 years. > ><>> 8/S.. I am going to put some highvoltage diodes between the 8/S,8I and ><>> scope to make sure if the scope goes bananas I don't blow a few hundred ><>> transistors in the minis. > >???? Why? The scope is an enclosed system that would be hard pressed to >emit high voltages back into the system it's hooked to. It's not like the >HP9100 in that respect. For the RM503 to do that the HV lead would have to >fall on one of the input lines! As I remember the series 8 Display scopes >were driven off a pair of D/As and some single bit output to blank the >beam. If you have something different I'd like to hear about that. Three D/As. 1 12 bit for x, 1 12 bit for y, and 1 3 bit for intensity. When the transformer went in this RM503 it raised the regular voltages throughout the scope to 500+ volts... in some places over 1000. That was present right through to the input. I am protecting the D/A converters as I don't need the PDPs taking major beatings in the future. All the supplies inside the scope (-100,100,250,85,-3000 were going nuts). The other RM503 I have has the same problem. I am going to put an isolation transformer on every RM503,RM560 scope I get to solve the problem ahead of time. The 8 Display controllers have the intensity option :-) (for spacewars of course). The AX08 (XR option) and the 34D (standard) had a 3 bit intensity D/A output for the scope. The RM503s were modified by DEC for intensity control. john PDP-8 and other rare mini computers http://www.pdp8.com > >Allison > > >

25 years

AOL members 2nd class citizens? (was Re: This guy needs a *LART*... :-/)

by SUPRDAVE＠aol.com

In a message dated 12/5/99 2:53:59 PM Eastern Standard Time, Glenatacme(a)aol.com writes: > Bruce Lane wrote: > > In a message dated 12/05/1999 12:08:55 AM Eastern Standard Time, > kyrrin(a)bluefeathertech.com writes: > > > The guy's an absolute moron, as is clearly evidenced > > by his poor spelling. The fact that he's posting from an AOL address, and > > that he has no feedback listed whatsoever, won't help either. > > Umm, just out of curiosity, why do you consider an AOL address "unhelpful?" > > Glen Goodwin > 0/0 well, its a very old and popular stereotype that aolosers are very new to computers and dont have a clue as to what the big picture is. DB Young coming in 2000: www.nothingtodo.org ! --> this message printed on recycled disk space view the computers of yesteryear at http://members.aol.com/suprdave/classiccmp/museum.htm (now accepting donations!)

25 years

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test-drb December 1999