Re: H-11 Updates

> On Apr 9, 2016, at 7:19 PM, Richard Cini wrote: > > All — > > It’s been a productive two weeks with my pseudo-DEC Heath H-11. I got myself > an Emulex UC07 SCSI card and a SCSI2SD SCSI drive emulator. After a week of > noodling around with why the on-board diagnostics

RE: Voltage regulator with alternate voltage source...

Brent Hilpert wrote: > Well that's neat. Thanks. > I assembled the Cromemco kit version of the Cyclops > (The kit version presented an interface for a computer > rather than the scope drive of the magazine article. I was recently able to acquire the S-100 interface cards for the Cyclops. I'm

H-11 Updates

All — It’s been a productive two weeks with my pseudo-DEC Heath H-11. I got myself an Emulex UC07 SCSI card and a SCSI2SD SCSI drive emulator. After a week of noodling around with why the on-board diagnostics wouldn’t load (stupid LTC jumper) I was able to confirm that the board and SCSI2SD

DEC LPS11 Laboratory Peripheral System for PDP-11

I saw a DEC LPS11 Laboratory Peripheral System for PDP-11 somewhere and was thinking of getting it just because of the Digital nameplate, but I was too broke. Now I see that an ebay listing[1] of it has the ambitious Buy It Now price of $1600 -- but that's with cabling and a book of schematics,

Re: Stuff searching for new home around Duesseldorf, germany

I have a 3800 for free, Its in Portland Oregon USA. May take a couple months to get all the parts together but it was complete around 10 years ago was said to have one of the proc. drawers dead. Anyone interested email me. -pete On Sat, Apr 9, 2016 at 6:43 AM, Noel Chiappa

Re: ADM 3a with no horizontal scan

On 04/09/2016 01:21 PM, Seth Morabito wrote: > I'm fairly surprised that the 7805 regulators died, and that they > present this symptom (no horizontal scan) upon their death. I'm sure > there are other marginal components that will need to be replaced, > so the restoration is not yet complete

Re: ADM 3a with no horizontal scan

Well, since it was such an easy job, I took a chance and replaced the two suspicious 7805 voltage regulators. The terminal works just fine now! http://imgur.com/a/wharu I'm fairly surprised that the 7805 regulators died, and that they present this symptom (no horizontal scan) upon their

In search of VAX 8550 or similar...

Would like to purchase and restore a big mid-80s VAX. Stupidly passed one up recently. Let me know if you have one you'd be willing to part with- also open to trades. In the Seattle area, but a little too comfortable with arranging freight shipping... Sent from Outlook for iPhone

Re: Voltage regulator with alternate voltage source...

Bill, surely you have a pile of 1N400x diodes someplace. Put 6 in series, forward, between the input and supply. That should ensure it is safe. If the voltage is higher than 8 volts, it would mean there isn't enough current to worry about. Dwight

Re: ADM 3a with no horizontal scan

Try renewing the thermal compound. Also, look for any really hot components on the 5V lines. Tantalums don't always smoke. A lot of older circuits also used a shunt resistor across the regulator to share part of the load. These were usually the square wire wound resisters. These often fail because

Re: A tale of a chip and a socket

On 04/09/2016 5:29 AM, Noel Chiappa wrote: > From: Torfinn Ingolfsen > Most likely a bad solder joint. That was my first thought, and so I carefully inspected all the pins, but they all looked good to me. But I suppose it might have been something that wasn't visually obvious.

Re: Stuff searching for new home around Duesseldorf, germany

> From: Peter Koch > rumours are that kids do place stuff like this into their parents > basement :-) I've even heard rumours of parents placing stuff like this into their kids basements! (I certainly have some PDP-11's in my daughter's old bedroom! :-) Noel

Re: A tale of a chip and a socket

> From: Torfinn Ingolfsen > Most likely a bad solder joint. That was my first thought, and so I carefully inspected all the pins, but they all looked good to me. But I suppose it might have been something that wasn't visually obvious. Noel

Stuff searching for new home around Duesseldorf, germany

Hi all, we have been using two Sun 6800 (each fully equipped with 96GB of RAM and 24 Sparc III processors 1.2GHz) for many years. Now they are retired and must leave our machine room to make place for newer machines. Anybody out there willing to give them a new home? They are very good in

Re: A tale of a chip and a socket

On Fri, Apr 8, 2016 at 11:19 PM, Noel Chiappa wrote: > So I just had the incredibly amusing experience of managing to repair an > -11/04 CPU by un-soldering a chip, putting in a socket, and putting _the same > chip_ back in that socket! > > Before you go 'WTF?!?!', let