Re: Atari PSU with collapsing 5V rail

2017-08-21 Thread Adrian Graham via cctalk
> On 20 Aug 2017, at 23:20, Chuck Guzis via cctalk > wrote: > > On 08/20/2017 12:12 PM, Brent Hilpert via cctalk wrote: > >> If the transformer were faulty and heating up internally, it would seem >> unlikely that it would cool off that quickly to recover, IME it takes some >> time for a tra

Re: Atari PSU with collapsing 5V rail

2017-08-21 Thread Adrian Graham via cctalk
> On 20 Aug 2017, at 23:20, Chuck Guzis via cctalk > wrote: > > On 08/20/2017 12:12 PM, Brent Hilpert via cctalk wrote: > >> If the transformer were faulty and heating up internally, it would seem >> unlikely that it would cool off that quickly to recover, IME it takes some >> time for a tra

Re: DCC-116 E / DATA GENERAL NOVA 2/10 / Nixdorf 620 - Restoring and restarting

2017-08-21 Thread Brent Hilpert via cctalk
On 2017-Aug-21, at 8:46 AM, Dominique Carlier via cctalk wrote: >> As is typical for power supplies of this type and era, this power supply >> includes current limiting circuitry. >> >> The current-limiting circuitry will throttle down the output voltage (not >> shut it off completely) as the

Re: DCC-116 E / DATA GENERAL NOVA 2/10 / Nixdorf 620 - Restoring and restarting

2017-08-21 Thread Dominique Carlier via cctalk
Because I had removed every wires to test transistors on A1 and A2, and since I have to buy 4 new 0.1ohm resistors and an equivalent of 2N6254, in the meantime because they are identical I decided to interchange A1 and A2, I was hoping note a +5V collapsed on the other output but no, it is alwa

Re: DCC-116 E / DATA GENERAL NOVA 2/10 / Nixdorf 620 - Restoring and restarting

2017-08-21 Thread Dominique Carlier via cctalk
Hello, Yes, it is a "Fluke 73" maybe not enough accurate for that kind of measurements ? On 21/08/2017 18:53, Anders Nelson via cctalk wrote: Hi Dominique, Are you using a standard DMM to make your resistance measurements? If not, you may have more consistent results by using a laboratory D

Re: DCC-116 E / DATA GENERAL NOVA 2/10 / Nixdorf 620 - Restoring and restarting

2017-08-21 Thread Anders Nelson via cctalk
Hi Dominique, Are you using a standard DMM to make your resistance measurements? If not, you may have more consistent results by using a laboratory DMM that is rated to measure milliohms. On Mon, Aug 21, 2017 at 11:47 AM Dominique Carlier via cctalk < cctalk@classiccmp.org> wrote: > > Thank you

Various Software and Documentation for shipping + donations (round 8)

2017-08-21 Thread Tapley, Mark via cctalk
All, More of the stack. if any of this interests you please contact me via Private (not list) email at mtap...@swri.edu. If you do want something, send me your shipping address and exactly what you want. I'll get back to you with estimated shipping costs (USPS media rate where p

Re: Atari PSU with collapsing 5V rail

2017-08-21 Thread Jules Richardson via cctalk
On 08/21/2017 10:06 AM, Chuck Guzis via cctalk wrote: Well, to throw some kerosene on the fire, this from Wikipedia: :-) "According to etymologist Jan Freeman, the story that duct tape was originally called duck tape is "quack etymology" that has spread "due to the reach of the Internet and t

Re: DCC-116 E / DATA GENERAL NOVA 2/10 / Nixdorf 620 - Restoring and restarting

2017-08-21 Thread Dominique Carlier via cctalk
Thank you very much for these valuable detailed information! :-) Also following the suggestions of Curious Marc, I focus now on the comparison between the two almost identical circuits that deliver the regulated + 5V on G2. Following your explanations, I started by checking the transistors a

Re: Atari PSU with collapsing 5V rail

2017-08-21 Thread Chuck Guzis via cctalk
On 08/21/2017 07:32 AM, Jules Richardson via cctalk wrote: > And if we're talking WWII, wasn't it duck tape? Duck cloth with an > adhesive layer. "Duct tape" came later... > > I wonder if we're being messed with ;-) Well, to throw some kerosene on the fire, this from Wikipedia: "According to et

Re: Atari PSU with collapsing 5V rail

2017-08-21 Thread Jules Richardson via cctalk
On 08/20/2017 01:57 PM, Mike Stein via cctalk wrote: Well, if we're going to nitpick it's _baling_ wire as in tying up bales of hay; bailing is for leaky boats. And if we're talking WWII, wasn't it duck tape? Duck cloth with an adhesive layer. "Duct tape" came later... I wonder if we're bein

RE: DEC VT125 on Schpock in Birmingham, UK

2017-08-21 Thread Rob Jarratt via cctalk
> -Original Message- > From: hollo...@gmail.com [mailto:hollo...@gmail.com] On Behalf Of Pete > Hollobon > Sent: 21 August 2017 12:52 > To: r...@jarratt.me.uk > Cc: General Discussion: On-Topic and Off-Topic Posts ; > Paul Anderson > Subject: Re: DEC VT125 on Schpock in Birmingham, UK >

Re: DEC VT125 on Schpock in Birmingham, UK

2017-08-21 Thread Pete Hollobon via cctalk
On 20 August 2017 at 19:45, Rob Jarratt wrote: >> -Original Message- >> From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Rob Jarratt >> via cctalk >> Sent: 19 August 2017 23:33 >> To: 'Paul Anderson' ; 'General Discussion: On-Topic and >> Off-Topic Posts' ; 'Pete Hollobon'