> First, in general, there are so many apparent reviews of so many products, it
> is hard to believe they are all scams. How can there be enough fools to buy
> enough of those products to have that many different ones?
I see you're new to the intersection of the audiophile world and online
> Well, I can submit a correction, but does anyone remember /dev/drum? I
> don't recall that in V6m or V7 Unix, I guess I could fire one of them up
> and see
There's at least references to /dev/drum in 2.11BSD, I forget if it was in the
docs or actually important stuff in the source. I don't
> 1. I have read that the card and the drives were compatible with the dec rx02
> drives. Why would the CRDS even bother to redesign a card where DEC had
> perfectly good working ones? Anyone know if there is any value in keeping the
> FC-202 or just keep with the DEC cards?
A lot of the
> Been lurking for a while, but this topic hits true with some recent
> experiences. I would not hesitate to buy most common digital ICs on Amazon
> or ebay
I mean we had to stop buying 7400 series from Jameco over counterfeits, so it's
definitely a problem for jellybean parts too. We had so
> Standard TTL 74XXX is drying up rather quickly. Futurlec still has some
> TTL but 7404s are all gone. Even LS is hard to find.
Ours comes from Mouser, between two part #s they have over 7,000 74LS04s in DIP
packaging in stock. Didn't check ACT, HCT, or ALS. I don't think we've had a
7400
> I had no idea they made a System Zero. I have a System One FWIW.
Apparently a lot of folks, even those actively hacking on S-100 stuff, don't
know about the System Zero! I've had a number of folks say as much. It's
definitely a real product, I had a purchase lined up for one a few years ago,
All,
I'm looking for a Cromemco System Zero, doesn't matter if it's empty or not.
Please contact me off-list if you have one to sell/trade or know of one!
Thanks,
Jonathan
All,
I'm looking for an image of the ROM or companion diskette for the Maxim MAX180
Evaluation Kit (MAX180EVKIT). I've got one that has a custom application ROM in
it.
Thanks,
Jonathan
> This apparently is true of some capacitors as well, I'm not sure which types.
It is true of all capacitors (CRTs are intentional capacitors, after all)
designed for and subjected to sufficiently high voltage. It's referred to as
dielectric absorption, and is why HV caps ship from the factory
> I agree with Don on the interference. We have a very high noise floor
> here in Toronto as well as being on the fringe
IIRC there's something on-frequency in England that often swamps WWVB on the
northeastern part of North America, too!
Thanks,
Jonathan
Bill,
If it's an older clock it's probably tripping over a timecode transmission
format/modulation change. I forget the exact details but changes were required
to my old 8085-based Spectracom receiver.
Thanks,
Jonathan
On Sunday, January 14th, 2024 at 14:49, Bill Gunshannon via cctalk
> Next step will be trying the same on my UltraBook (DS1643 instead of DS1553
> on the UltraBook IIi). But need to Xray that one first before attaching a new
> battery.
I have a DS1643 replacement prototype if you're interested.
Thanks,
Jonathan
Very cool, thanks for sharing! I didn't know such a tabulation existed!
Thanks,
Jonathan
--- Original Message ---
On Monday, October 2nd, 2023 at 13:12, Shoppa, Tim via cctalk
wrote:
>
>
> For those working with ex-Soviet equipment from the 60’s and 70’s here’s a
> remarkable
Booted the SPARCbook 3, its battery is in fact dead, and aside from taking a
little longer to come up (totally expected) it's fine.
Thanks,
Jonathan
--- Original Message ---
On Thursday, September 28th, 2023 at 07:41, Jonathan Chapman via cctalk
wrote:
>
>
> Yet we h
Yet we have a few datapoints showing that a dead NVRAM/RTC still boot
UltraBooks just fine! As I said, I personally confirmed with my UltraBook IIe.
Pretty sure the NVRAM is dead in my SPARCbook too, I can confirm that today.
Thanks,
Jonathan
--- Original Message ---
On Thursday,
> Hi Jonathan, thanks for your thoughs. I am still using the same NVRAM, just
> with external battery attached, so no Chineese counterfeit.
> My hypothesis is: With the battery losing voltage, some bits flip first. They
> cause the error message you see and values get set to proper values. But
> Interesting - did you youse some modern technology for
> doing that?
Modern "special sauce" replacements from Dallas/Maxim/Analog/etc., plus a fast,
low-power SRAM, all packaged on a circuit board with Batten & Allen DIP
leadframe pins, like this:
> Speaking of dumping...
>
> Is it possible to read a Dallas DS1643 in programmer? That's what's in my
> Ultrabook. I just tried with a Topmax II that supports it and I get all
> zeros. :(
You probably need to make a shim socket and pull pin 26 to VCC (pin 28), then
read it as a DS1225. I'd
/me hears mention of dead NVRAMs and materializes
Pulled out my UltraBook IIe today, it's fine with a dead NVRAM, just gives you
the usual "IDPROM contents are invalid" message you see on Suns.
If I'd have to guess, based on past experience, you likely have a counterfeit
DS1553W or you ordered
> Do you know of a source for drivers and software for the PC environment
> for this equipment? I was recently given a 1054 which is supposedly the
> same system with a SCSI interface. I've yet to find anything online.
> Any suggestions would be most appreciated!
The version with SCSI (it's a
> Other than graphics (and maybe some special function keys for an application
> on a keyboard), why would an S-100 builder in those days opt to buy a video
> card instead of a terminal?
Primarily cost I'm led to believe. There were also games that took advantage of
primitive graphics
Marvin,
You and I had talked about reproductions of some of the Poly 88 stuff at VCF MW
in I think 2018. We're currently working on that project, Connor Krukosky
recently spent a week down here capturing dimensions on both the old and new
style cases and covers! We're currently nailing down
> Anyone seen those before, and is it actually SCSI, or is it something else?
Common on old Sun SCSI stuff, it's a DD-50. Could be something else, but they
were indeed used for SCSI termination.
Thanks,
Jonathan
> Is that somewhere in Maryland?
Yeah, Cockeysville, just outside Baltimore off I-83.
Thanks,
Jonathan
I'm going, there's going to be a fair bit of Ohio Scientific hacking going on
this weekend. We're going to try and get my CD-23 hard disk system up and going
and pull data off it (14" Shugart SA-4008)
Thanks,
Jonathan
--- Original Message ---
On Tuesday, July 18th, 2023 at 19:56, Mark
> It helps if you're running a version of *nixand not fenestrae.
Helps, but is not the near cure-all it was at one point, especially for the
larger/more popular distros!
Thanks,
Jonathan
HLDA should be deasserted, that puts the processor in a DMA mode where it
releases all the control signals.
I/O W is asserted low when OUT is high and the low WR pulse comes along. It's
both status and timing, coming out of the 8228.
You would probably do well seeing if MEMR and MEMW are
> Not necessarily a DEC thing. TEMPEST PC's (and other TEMPEST boxes like
> fiber
>
> ethernet transceivers) also had screw connectors rather than the spring
> clip ones.
It's semi-common on random old stuff, yeah. I've got a Cisco IGS that uses
jackscrews, and have had a pretty good number of
> There is no real equivalent of an 'AUI null modem cable' (should that
> be 'null transceiver cable'?)
>
> If you want to link 2 computer-type ports together you need the
> equiavelent of 2 transceivers.
This (or devices like it) is probably the only single-piece two station "null
modem
> There is also DD, though I've never seen one in the wild.
Old SCSI uses DD-50. I've also seen it used on Pertec tape controllers and
multiport serial cards.
Thanks,
Jonathan
> For a few inches, which would be enough here I think, I've used an IDC
> DA15 plug and socket crimped onto the normal ribbon cable. Technically
> it's wrong but the reflections on that length of cable won't matter.
That's how Sun VME Ethernet boards are set up, the board itself is way back
These are my go-to for short ones:
https://www.ebay.com/itm/233295839501
Not affiliated with seller, just a satisfied customer.
Thanks,
Jonathan
--- Original Message ---
On Tuesday, June 27th, 2023 at 21:16, Chris Zach via cctalk
wrote:
>
>
> Anyone in MD got an AUI cable (few
> I believe the 10Gb standard specifically prohibits autonegotiation, so
> 10G should not drop down to 1G or 100Mb/s.
It drops down to 1gig just fine, at least on everything I've tested. This is of
course over copper, not optical.
Thanks,
Jonathan
Best thing to do is keep an old 10mbit switch or hub around with 100mbit or
gigabit uplink. Second best thing is to have a router that will talk 10mbit
half duplex.
I've also found some poorly behaved stuff that won't autonegotiate duplex even
with older switches, like my 3Com SuperStack II.
Everyone lost the metal strip! It's sandwiched in between the trim of the outer
case and the dress panel. Some folks stuck it to the dress panel with glue,
double-sided tape, etc. Those are usually the machines which still have the
metal strip.
Thanks,
Jonathan
--- Original Message
> Make of that what you will, but if that isn't just a slander, that's the
> guy upon whose legacy everyone is relying.
Everyone knows (or ought to, at this point) RMS is a weird guy and at best
makes some seriously questionable life choices and misinformed public
statements. There's a reason
> FSF does not enforce anything. I repeatedly begged for help with Desktop
> CYBER which was GPL licensed and they did not even bother to reply.
I'm told by a friend at Red Hat that RH/IBM has a department for that kind of
thing and can/will provide legal help for outside projects.
Thanks,
> If you posted your design as Open Source, someone else producing it isn't a
> knockoff, it's the system working as intended.
What is it when the design is open source, but they're not complying with the
terms of the license? That's what really bugs me, the "cost" of producing your
own from
> But, as some who worked
> to bring a product to market only to see people on forums say "Skip
> buying it from Jim for , you can build the same thing by yourself
> for $ from AliExpress parts or buy this eBay knockoff for 2X$", I will
> admit that is somewhat infuriating. If the hobby
> On HP: yes, perhaps. I used one of those back at DEC, in the mid 1980s. Nice
> machine, but my suspicion is that I'd run into the small memory problem again
> that plagues me with the Philips/Fluke analyzer I use right now.
We use several HP analyzers around here, all from the 80s. Even the
All,
I went to find a page about P Surplus to link to a friend who'd never been
there, and this was today's top result:
https://www.dailyfreeman.com/2023/02/19/pt-surplus-in-kingston-struggles-as-owners-battle-illnesses-mounting-bills/
Apparently Mr. Smythe is having hard times with his
> So, what else do you guys use, to make sure your data is safe for the
> years to come?
ZFS and redundant copies of important stuff, plus backups on media that's
likely to be readable in 10 years (meaning the drives must still work/be
available, too!)
Anything that's appropriate to have on a
> I find myself wondering, how well does CD-R and DVD-R media that hasn’t been
> used age?
Anecdotal, but I have some Fuji blanks from the 90s that still burn just fine
(works great on old drives that hate modern "see-through" media). The DVD-Rs I
have were bought by my parents in the
All,
I've been looking for a Kinetics or Shiva FastPath 4 or 5 for a while, without
luck. Don't know why I didn't think to ask on the various lists! If anyone has
one they'd like to part with, let me know off-list.
Thanks,
Jonathan
If the PSU requires too much hacking, you may just want to replace with a
modern Mean-Well switcher or two. The Aztec supplies used in those Xerox
enclosures are OK but nothing stellar. I recapped mine (it also showed signs of
electrolytic leakage) and it did work so I kept it, but if it'd had
> If it's gold and got RIFA on it, replace it, though.
- snip -
> I've learned now, to always check every PSU or other mains-powered
> vintage equipment for these little stinkbombs. If they're present, i'll
> always replace.
Yup, always replace. These are not parts that can be rehabilitated.
> From the USPS Domestic Mail Manual, section 170, subsection 4.1(i):
>
> "Computer-readable media containing prerecorded information and guides or
> scripts prepared solely for use with such media."
I've asked and our postmaster has said anything that's not blank is OK (we ship
a lot of
I finally herded together the extant pictures of the KIM-1s I've had in the
past and did a writeup:
http://www.glitchwrks.com/2022/09/18/kim1-boards-past
TL;DR is that during college I found a KIM-1 in an employer's warehouse. Later,
I found a box with five more! These were all Virginia Tech
> It turns out that some 8" drives can be set to separate the sector holes
> from the index hole (separate output pins for index and sector). Doing
> so, gives you what amounts to a soft-sectored floppy, regardless of what
> the physical object is.
The flippy 8" diskette I linked a picture of
> BTW, the greaseweazle can format RX01 format diskettes quite nicely.
Any PC that can do single-density can (with ImageDisk or similar), as well as
basically all CP/M boxes with 8" drives. That's how I format new RX01 media.
RX01 can of course be up-converted to RX02 format with XXDP.
Thanks,
> Someone suggested punching a notch in them and using both sides.
> Was that even possible on 8" disks?
Sure, but you have to punch an offset index hole:
https://imgur.com/a/6vdR6NE
That's a single-sided flippy 8" diskette (it's also hard-sector but that's not
really relevant). 8" diskettes
> I think it was Dysan that first showed up with reinforcing ring kits
Probably, "Grabettes."
> Then why was is it that DD media bought well after HD media was available, in
> use, and the norm still had the reinforced ring? Tradition?
You might be putting it in an old drive. It was also
> The last time I checked, bitsavers had information on the 1015, 1016 and
> 1115 floppy drives (I have all three models). Did the VG use something
> different?
No, but I didn't find the model numbering w.r.t. first chassis vs. expansion
chassis very clear, especially between the older "blue
I stumbled across that the other day, looking for information on their 100 TPI
drives commonly used with Vector Graphic stuff. I was very surprised to find it!
Thanks,
Jonathan
--- Original Message ---
On Tuesday, August 16th, 2022 at 03:42, P Gebhardt via cctalk
wrote:
>
>
>
I have a friend who has one of the wire rack RL style pack racks, which looks a
lot like the one pictured. I've thought about having a wireform manufacturer do
a run of them. Aforementioned friend is willing to loan it for dimensional
capture/reproduction. Is this something people would be
All,
Per the LAN-attached serial thread, here's another cheap Lantronix device:
https://www.ebay.com/itm/123577635191
This is a LRS-2, which is basically a two-port LRS-1, one of their older models
of serial bridges. The LRS-2 is nice not only for the two ports, but because it
also has AUI
> When I looked at the manual for the Lantronix UDS1100 I did not see any
> mention of it being able to be used as Telnet client.
PDF Page 54.
You put it in manual CONNECT mode, modem emulation, and type
"ATDT10.20.30.40:23" on most modern Lantronix devices. I have no personal
experience with
> At least that's how I would configure things
Yeah that's basically it. You can often assign aliases so that e.g. `CONNECT
RAID` executes a Telnet to a specific IP/DNS name, and many support setting up
a default or automatic connection so that as soon as the terminal autobauds it
just
> i.e. there is no device that make a shell or a telnet client available to a
> terminal and I will have to roll my own.
You may of course choose to DIY but there have been several common and
cheaply-available-used solutions presented to you. The default behavior of most
terminal servers
> I have used the Lantronix UDS1100 for Ethernet/RS232 bridgingmaybe too
> pricey new, but available on ePay
The older models (LRS-1, LRS-2, UDS10, etc.) also work fine. If you have more
than one terminal, look at a small terminal server. There are a few terminal
server models that go for
Doug,
> A few years ago I got it to power on and it runs Unix variant, their
> product name was Idris. I have 16 floppies (dated 1992) that came with
> the system, but the hard disk has died.
Interesting! I have a Multibus system that runs Idris, very little information
seems to be around on
We do hosting for a few other hobbyists, and Andy Meyer has his Sony SMC-70
pages on users.glitchwrks.com subdomain:
http://users.glitchwrks.com/~ahm/smc70/
Not really advertised as a service, just one of those things where a few
friends have needed a place to host a few things!
Thanks,
> I ended up getting a PCI bus PC Card adapter based on the TI PCI1131
> PCI-TO-CARDBUS CONTROLLER UNIT chip. I set that up in a Linux system
> and eventually managed to get some MTD (Memory Technology Devices)
> software installed so that I could read and write to a variety of
> linear flash
DeOxit works pretty good for cleaning up connectors that still have serviceable
surface finishes, but yeah, temporary at best if the surface finish is gone. We
use it to clean up all sorts of connectors that are just regular dirty, pots,
etc.
Thanks,
Jonathan
--- Original Message
> Copper? Mine all look like solder. Probably copper underneath but
> the exposed part is lead which probably explains why they seem to
> corrode so easily.
Ah, yeah, if they're finished in matte tin or HASL, I just reflow leaded solder
on. A little bit of Superior #30 flux will make it flow
If there's bad/deep corrosion, I hit it with the ink eraser (I have a bunch of
Eberhard-Faber ones that look like a wooden pencil, you sharpen them like a
pencil too). If that won't touch it, I use the stainless steel toothbrush.
Corey Cohen has some plating solution that you dip a pen in,
> Dang! That Z80 computer looks AWESOME.
Sure does! Simpson 260 sitting on the bench too :P
Thanks,
Jonathan
Bill,
Let me know right quick if you'll be at VCF East and I'll make you a pair, I
have both kinds of IDC ends. I'm heading out first thing tomorrow morning
though as I have work in the northeast before VCF East.
Thanks,
Jonathan
--- Original Message ---
On Monday, April 18th, 2022
> SSD's are a different beast, if you're going to put data
> on them that you do not want recovered I would recommend encrypting the
> drive before using it, then when done delete/destroy the key. That
> should turn your drive into a useless (but format-able) chunk of silicon.
That's our take on
> What surprises me (a little) is that there is a commercial outfit
> willing to work on something so old.
It's essentially what we do. I doubt there's a directory of all the small shops
that work on legacy equipment, but consider that some of this stuff runs CNC
machines that are still in use.
> I always forget that the VAC is the RMS and not the peak-to-peak. I will
> look for a minimum rating of 100V.
600V bridge modules are often more cost effective, and more likely to be in
stock. That's why I went with the Vishay part I used.
If you can't find what you need due to shortages, you
I used a Vishay GBPC3506W-E4/51, which is 600V 35A, 400A inrush rated. Looks
like they're currently on-order at Mouser, I don't know about other suppliers.
The GBPC3506W-E4/51 is a little thinner than the bridge rectifier DEC used
originally, which sometimes matters. For the 5411086 board in my
Wow, that was quick! Mouse acquired.
Thanks,
Jonathan
--- Original Message ---
On Friday, February 11th, 2022 at 10:06, Jonathan Chapman via cctalk
wrote:
> All,
>
> I'm looking for a DEC VSXXX-AA "hockey puck" mouse or compatible for a
> VAXstation 3100.
>
> Thanks,
>
> Jonathan
All,
I'm looking for a DEC VSXXX-AA "hockey puck" mouse or compatible for a
VAXstation 3100.
Thanks,
Jonathan
;
> "I put a new module in my router. It blew up. At least it meant well" :-)
>
> (My IGS has the rather heavy and over-engineered divider shelf with the
>
> main board underneath and the fan and power supply above.)
>
> Regards,
>
> Peter Coghlan
>
> Jonathan
With that much carnage, I'd probably drop a Mean-Well module in there. I
believe there would be enough room for one or two in the IGS I have (taller
white box, divider "shelf" over the mainboard, I don't know if there was a
lower profile model).
Thanks,
Jonathan
--- Original Message
Get yourself a largeish 24V transformer, I use an old 8A Stancor:
http://www.glitchwrks.com/images/dec/pdp1110_psu_repair/5411086_under_test.jpg
The AC input can be between 20-30V so it's not critical. Plenty of other
"control transformer" type units would do fine.
You shouldn't need a lot of
I recently dealt with this with the DaJen SCI monitor listing out of the
manual. The copy is pretty bad, and either their printer was having issues, or
slashing of "zero" vs "O" was inconsistent somehow. OCRing it produced more of
a mess than just sitting with the original and a text editor
> He has a lot of Exorciser boards and manuals to scan so I will let him
> step forward when he's ready for that. But I do greatly appreciate
> getting this manual.
Nice! Looking forward to that manual dump when it does happen. I haven't done a
ton with EXORbus due to the lack of
> Excellent information Jonathan!
Glad to share! I get the impression that people often think I'm on some
ideological soapbox when I tell them not to use $flybynite_pcb but really there
are big differences in quality.
> I generally carry the s100computers and many RetroBrew board
Thank *you*
to order some boards for my PDP-8/E but I've never ordered boards
>
> before.
>
> What board house do you use? Have you ever specified gold fingers before?
>
> Any advice would be greatly appreciated.
>
> Thanks,
>
> Mike
>
> +1 (773) 414-1044
>
> On 1/19/2022
2 at 10:24, Chris Elmquist via cctalk
wrote:
> On Wednesday (01/19/2022 at 03:35PM +0100), Jos Dreesen via cctalk wrote:
>
> > On 19.01.22 13:15, Jonathan Chapman via cctalk wrote:
> >
> > > That's a neat board! Where can I/we order one?
> >
> > With
Just as a follow-up, I retensioned and read both tapes with clear bands this
morning, and they're fine. Since they were parked, there shouldn't have been
anything important there, and it looks like the removed oxide is staying on the
band.
Thanks,
Jonathan
‐‐‐ Original Message ‐‐‐
On
That's a neat board! Where can I/we order one?
Thanks,
Jonathan
‐‐‐ Original Message ‐‐‐
On Wednesday, January 19th, 2022 at 04:08, jos via cctalk
wrote:
> On 19.01.22 01:22, Chris Elmquist via cctalk wrote:
>
> > On Tuesday (01/18/2022 at 11:35PM +), Jonathan Chapman wrote:
> >
How's about a Glitchbus board set that's compatible? I was planning on doing it
anyway.
Thanks,
Jonathan
‐‐‐ Original Message ‐‐‐
On Tuesday, January 18th, 2022 at 16:45, Chris Elmquist via cctalk
wrote:
> On Tuesday (01/18/2022 at 03:37PM -0600), Mike Katz wrote:
>
> > If the
> However, "couple (of) months" seems incongruent with "day-to-day".
I don't do a reinstall of SunOS every day, though!
> I am assuming that the day-to-day operation to mean that the source data
> is still accessible on the source system. As such, it's probably simply
> a matter of annoyance
> I wince at the idea of running with QIC tape. But my experience is with
> QIC-80 tapes of the '90s
Yes, small ftape QIC-80s were certainly in the "not great" category!
Thanks,
Jonathan
> My opinion is that if you're trying to use DC carts for archival
storage, you should have your (tape) head examined.
Not archival storage, just day-to-day operation on old stuff, like Sun3/Sun4,
AT UNIX PC, etc.
> As someone that has worked with computer tapes for nearly 40 years, I have to
https://i.imgur.com/48EfOQG.jpg
That's after sitting parked a couple months. I have a Dysan doing it too. The
Dysan had been re-banded with a boiled 3M band and run for years like that with
no shedding. I have another Dysan with a green Plastiband in it which is also
fine, minimal/no shed. So,
> Note that both have a minimum order :-<. As for pins:
If folks don't want to deal with minimums, we can make up cables with the
correct connector, we stock the housings, crimps, and have the correct TE crimp
tool for them.
That said, connectorpeople.com are good to deal with, we use them for
> The terminal posts are aluminum, and can develop an oxide
> layer that prevents good contact.
>
> Removing and replacing them might improve the contact.
I have experienced this personally with TO-3 regulators, too. I had a bunch of
triple voltage Power One linear supplies that would
> One of the H744 regulators whines
FWIW, none of mine are silent under load. If they're not being loaded (e.g. on
a test bench, with no dummy load, or if you have all the boards out) they can
whine excessively due to no minimum load.
> it seems higher than the expected values printed on the
> Why couldn't 120V be derived from either of the 240V phase and the
> grounded corner via a 2:1 transformer?
It can. That's often how, say, an Edison base decorative luminary is run when
all other lighting is 277V (the ratios would of course be different). Otherwise
someone invariably screws a
> For what it's worth, the building I bought has two services installed when
> it was built in 1921 - single phase 120/240 for lighting loads, and 240V
> Delta for three phase loads.
I bet you have a fun electrical system :D
> It's the even more obscure corner-grounded delta
I love the reaction
> The IIRC oldest US generating station still in operation (on original
> hardware anyway) is at Mechanicville, NY.
Well that ruined my evening, Wikipedia says the generating station now uses the
power to mine bitcoins, because it's more profitable than selling it to the
public grid.
Thanks,
> much of it related to Niagara Falls and other power systems
> modeled after it.
The IIRC oldest US generating station still in operation (on original hardware
anyway) is at Mechanicville, NY. It is hydroelectric and originally fed 40 Hz
AC to Schenectady. They just sped up the alternators
> High-leg delta is independent of open- or closed-delta.
That's correct.
> Open delta uses two single-phase transformers primaries connected to
> phases AB and BC.
A to C is also valid, presumably it's rotated if there's a lot of open delta in
an area (again, why?) to balance phases.
> On
Message ‐‐‐
On Tuesday, January 4th, 2022 at 14:56, Grant Taylor via cctalk
wrote:
> On 1/4/22 8:52 AM, Jonathan Chapman via cctalk wrote:
>
> > Indeed. This is not corner-grounded delta. Once you figure out open
> >
> > delta, look at dog-leg.
>
> I did so
> I apparently need to do more reading.
Indeed. This is not corner-grounded delta. Once you figure out open delta, look
at dog-leg.
Thanks,
Jonathan
> I have seen some roads where the utility has 2 of the phases plus
> neutral going down them, not true 2-phase power, but 2 phases 120/240
> degrees apart with the third phase just not present.
Yes, that's open delta. There are one or two small commercial buildings here in
town that still have
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