test-drb January 2005

test-drb@ccmp.vtda.org

254 participants
551 discussions

by melamy＠earthlink.net

one of the key specs for power transistors is operating temperature. When near the top end of dissipation, the case can be past the temerpature of boiling water and still be able to dissipate 60% of what its top rating is (typical for 2N3055 power transistor anyway). If you want to make absolutely sure, then get the part number and find the specs on it. Measure the case temperature and then the emitter and collector voltages. The difference between the two times the output current of 7.2 amps will give you the wattage it is trying to dissipate. Refer to the specs to see if the temperature vs dissipation is within spec. A simpler solution is just run it and see if it eventually blows up... (it is probably okay) best regards, Steve Thatcher -----Original Message----- From: Bill Sudbrink <wh.sudbrink(a)verizon.net> hot to touch. Is that normal operation for this kind of supply? Maybe I got a bad one from WeirdStuff? Or could this be some additional clue as to something wrong somewhere else in the computer? According to my meter, the voltage is spot on 5 volts and the current is 7.2 amps. Any suggestions appreciated.

19 years, 8 months

DNS history? (fwd)

by tomj＠wps.com

I asked my friend Randy who has done a lot of DNS work. ---------- Forwarded message ---------- Date: Thu, 13 Jan 2005 18:06:15 -0800 From: Randy Bush Subject: Re: DNS history? > Anything written? i googled. the first entry seems written by someone who could read rfcs and then add political spin. <http://www.byte.org/one-history-of-dns.pdf> <http://www.ahref.com/guides/industry/199903/0323piouprintable.html> is far too terse and short. nothing else looks interesting i would ask on inter-hist list randy

19 years, 8 months

Linux and growth of Internet

by classiccmp＠crash.com

John Allain wrote: > First home ISP: Public Access Networks (Panix NY) > running on Suns. A friend of mine was involved in the startup of Panix and has said several times that the original platform was A/UX, of all things. He's been on and off the list from time to time, maybe I can get him to tell the tale... --Steve.

19 years, 8 months

ebay HP book

by jwest＠classiccmp.org

Item # 5156451806 This is one of the best books to have for HP collectors. It pulls together many different manuals into one reference book. It's got a lot of hardware info, but you can almost think of this book being to the HP software what the CE handbook is to HP software. Lots of good stuff :) Jay

19 years, 8 months

What is this RK05 style pack?

by wacarder＠usit.net

A couple months ago I acquired a new, still in the plastic wrap, still in the box, never opened disk pack that at first glance appeared to be an RK05. I finally decided to look further at it to see if it was a 12 sector or 16 sector RK05 pack, since it had no identifying label or markings. Upon further inspection, I found that it did not have the usual rim on the hub, where normally you would be able to count the thin notches to determine whether it was a 16 sector or 12 sector RK05. Instead, it has a short, rounded, unnotched rim where normally it would have the tall thin rim with notches. Otherwise it looks just like an RK05. The case is interchangeable. I actually took it apart so I could use the case on another RK05 pack that had a decent platter but a bad outer case. What is this thing? RK03? Ashley

19 years, 8 months

Wanted: Used electronic / Computer resellers

by ICS＠Core.com

Anyone know of Used or Salvage Electronic / Computer equipment resellers in the Maryland, Virginia area? or of a Mr. Wilson Drummond that buys from the NASA auctions?

19 years, 8 months

Any one remember...?

by alhartman＠yahoo.com

Wow Eric! That was QUICK! Thanks! I'd be interested to hear about your experiences with this board. Do you like it? My original Model I is not working properly at this time. My friend Tom and I will have to take a look at it more closely. It powers up, and will work stand-alone, but when attached to my E/I or an LNW E/I I have, it does not see the RAM in the E/I or access the floppies. I may simply have to resolder the gold plug on the expansion connector, OR something more insidious is wrong. This particular Model I has the Dennis Kitsz LowerCase Mod from his book (very similar to the Electric Pencil Mod), Dennis's High Speed Upgrade (4mhz if I remember correctly) with a special circuit that slows down the Mod for Cassette or Disk Access (along with a Tri-Color LED that goes Red for normal, Green for High Speed, and Orange for Auto Switch). We also built in an Audio Amplifier, Composite Video Out (for an Amber Monitor OR a TV through an RF Modulator), AND an Alpha Joystick Connector one can attach ANY Atari-Style Joystick to. I miss those days... Al > From: dittman(a)dittman.net (Eric Dittman) > > > All this talk of TRS-80's on the list (Those two > S-100 > > Systems sound COOL!!!), prompts me to ask if > anyone > > remembers a garage project called "The Trash > > Compactor". > > > > Basically, some guy (a REALLY SMART guy!) > > reimplemented the entire Model III logic Board on > a > > board that would fit inside a Model I case. > > > > It also incorporated the E/I and the RS-232 port, > and > > did some other cool things. > > > > I lost the literature I used to have on this > board. > > > > Anyone remember it? > > I have a board that sounds like what you described. > The company > silkscreened on the board is "Norcom". > > The Model I case has part of the back plastic hacked > out for the > additional connectors. The keyboard is one of the > later-model > Model I keyboards with keypad. > > It works with the exception of one column of keys, > which should be > easy to fix when I get a chance. > -- > Eric Dittman > dittman(a)dittman.net __________________________________ Do you Yahoo!? Yahoo! Mail - 250MB free storage. Do more. Manage less. http://info.mail.yahoo.com/mail_250

19 years, 8 months

Any one remember...?

by alhartman＠yahoo.com

All this talk of TRS-80's on the list (Those two S-100 Systems sound COOL!!!), prompts me to ask if anyone remembers a garage project called "The Trash Compactor". Basically, some guy (a REALLY SMART guy!) reimplemented the entire Model III logic Board on a board that would fit inside a Model I case. It also incorporated the E/I and the RS-232 port, and did some other cool things. I lost the literature I used to have on this board. Anyone remember it? I wish I'd bought one, way back when... I'm STILL looking for an LNW-80 Model II.. __________________________________ Do you Yahoo!? Yahoo! Mail - You care about security. So do we. http://promotions.yahoo.com/new_mail

19 years, 8 months

"Cold heat" soldering?

by dwight.elvey＠amd.com

>From: "Tom Jennings" <tomj(a)wps.com> > >On Wed, 12 Jan 2005, Ron Hudson wrote: > >> What kind of screwdriver is a "greenie" screwdriver? > >I thought they were universal!!!! :-) > >about 4" long, thin flat blade, 3/32" or so, green translucent hex >handle, by xcelite. Trimpots, prying chips, cutting PCB traces, >punching holes in your pocket. Fancy models come with a pocket >clip. Decent quality, cheap. Just knowing I own one (actually, >three) makes life better. > I always referred to them as being a "tweak". A small piece of shrink tubing to slide up when doing trim pots. Dwight

19 years, 8 months

Thorn EMI Proton Detection System Commodore PET (UK)

by listmailgoeshere＠gmail.com

A friend of mine who works for a large local organisation rescued this fascinating piece of kit from being thrown in a dumpster. It is a modified PET (the later series without the cassette drive) with the "Commodore" name strip replaced with a "Thorn EMI" one. It is internally modified with one or several? more boards mounted in it, and there are several ports which have been added to the right hand side - these include two BNCs which IIRC were Analogue In and Analogue Out, a 25-pin D RS232, and several others I don't recall. The machine also has new ROMs in it - however the original ones are stored within it in a small perspex box attached to the baseplace (how thoughtful is that?). I didn't get to see it run. There is also a Commodore dual floppy drive for the unit with it (using half-height drives). Another contact I have at this place is a collector of old computers so I suspect he will have his eye on this, however he has a PET in his collection already, so if this unit is of particular historical importance and someone wants it for their museum where it will go on display (Witchy? Jules?) I might be able to get it for you on this basis. I could certainly try. Is anyone interested?

19 years, 8 months

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test-drb January 2005