Hello,
4 hours ago I posted an email concerning a huge amount of documentation
that I have. I also included about 30 pictures. I can find no
indication that this email was distributed. Is there a problem with
this information? Was it received?
Tony Pflum
Mathematically, circumference is PI times diameter or 3.14159. times
the diameter.
On 12/2/2015 11:06 AM, Fred Cisin wrote:
On Wed, 2 Dec 2015, Paul Koning wrote:
Actually, it's the circumference that matters, not the diameter.
I always thought that there was a relatively stable relatio
I am using Thunderbird 38.4.0 on a couple of PC's. I use Google
calendar for scheduling.
Tony Pflum
On 12/12/2015 3:08 PM, Dave Woyciesjes wrote:
On 12/11/2015 05:58 PM, Dave Wade wrote:
-Original Message-
From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of
wu
uter using VHF RF output.
-tony
with perhaps level-shifting resistors inside. So it will use the RGB pins on
the
SCART connector.
-tony
ls are on-line in German). They
culimated in making a monochrome TV, yes, the tuner and IF strip were
ready-built modules, as was the CRT PSU, but you still got to do a lot
yourself and, learnt a lot in the process. Perhaps looking at said manuals will
let you know what you
up against.]
-tony
going to be
connecting the RF signal straight from
the computer to this unit. Do you really need a _tuner_? You have essentially
one strongish signal. What about
an untuned receiver and demodulator? At VHF totally possible, UHF might be a
lot harder...
-tony
--
Mark J. Blair, NF6X
http://www.nf6x.net/
at the OP is planning on using an FPGA in his converter (not
surpisingly),
is the solution to have different configuration files for different machines?
So the
setup for an Apple ][ is optimised for its aliased colour, while that for a BBC
micro
handles 80 column text a bit better
-tony
are updated to use the latest
cheapest IC, you know which ones still work with which machines.
-tony
le 'figure
of 8' does exist,
but the version I have seen doesn't have a proper cable clamp.
-tony
s over here in the 1960s, just try finding one now.
Even standard connectors (some still in production) like the Bulgin 1.5A and 5A
ranges and the
XLR-like LNE connector are not that easy to get.
-tony
the cables packed in plastic
bags -- as you know the manufacturers of such things save every last penny and
would not include a bag if
there was no reason for it.
-tony
ither fuse (under different part numbers) in their
catalogue.
I can't be the only person to have a jam jar full of brand new 13A cartridge
fuses removed
from plugs I am fitting...
-tony
a nice little 20VA isolating transformer with a secondary tapped at
110V
and 220V has a lot of uses. And generally costs more than a pound...
-tony
uase
it has led to some very dangerous moulded mains leads, and in my case it has
just
caused a lot of moulded plugs to go to landfill (on principle I cut them off
and fit a
properly made, properly wired, plug).
But for some reason shavers (and electric toothbrushes?) seem to be exempt from
this.
Note that the 'shaver adapter' does not have to be included with a shaver.
-tony
my
normal commercial stand-alone exerciser couldn't handle), it seems to me this
is the sort of
thing you could trivially do with a microcontroller that has enough I/O lines.
-tony
he 'scope and drive exerciser.
-tony
an HPIB interface (I use an
HP9000/200
machine for this).
Make sure you get the pods/leads when buying a second-hand LA. They often go
missing, and are unobtainium. Making your own is not a real option, although
both the LA's I have mentioned have differential ECL inputs, so a TTL-on
as both HPIB and HPIL interfaces. In theory you can
control this thing from
an HP71B handheld (or an HP41 calculator?)
An HP1631 would be fun (it has a DSO board at the bottom as well as the LA
functions).
-tony
board, but
I think
that is the only change). The 1631 has an extra PCB at the bottom which
contains the custom
input and ADC circuitry to make it act as a digital storage 'scope too.
-tony
1990s over here, and uneven segment illumination due to low
emission from the filament
was a common fault. Conversely, my HP9815 and HP59304 are, AFAIK, still using
the original panaplex
display unit with no problems.
-tony
play
and therefore
the HV supply to drive it, uses neon bulbs (NE2 sort of thing) as status
indicators.
-tony
els until the mid 1970s? Things like the PDP11/45, Philips P850, etc
all used filament bulbs, not LEDs.
-tony
blanked under
certain conditions so it's not that you can use the display as a power-on
indicator on the smaller machines.
I like the power-on indicator of the 9815. It's a few ICs to display a row of
dashes across the display when
the display is not in use for displaying a number.
-tony
the serial number, it's early,
perhaps
315) certainly has bulbs.
Thinking about it, I find it surprising that on later disk drives -- RL's,
RK07s,
R80s etc, they used bulbs and not LEDs. By that date LEDs were easily available
and
reliable.
-tony
D on the surface of the button. That seemed quite a neat
device. I am sure DEC could have come up with something.
-tony
but I suspect most RC25 problems
are mechanical, not electronic)
-tony
the heads for both the fixed and removeable disks are on the same positioner
carriage. With the result that if you load the heads without a removeable
cartridge in place, those heads will touch each other, which is a good
way to ruin them.
-tony
version of the
RK11-D, took same
cartridges, same format, etc) with a fixed platter as well as the cartridge. Of
course the HP7900 was
like that too.
I never really liked the idea. The main problem was you lost access to the
fixed disk(s) while changing the
removeable one.
-tony
t this imply that
badge-engineered devices coudl result
in loss of trademarks.
-tony
x_ instruments (!)
-tony
I must get my 11/730 running again...
-tony
of work with vacuum systems. He
would swear by
Varian (and swear _at_ Vacuum Generators). I assume it was the same Varian
company.
A number of scientific instrument companies made computers too, of course. The
most obvious
being HP.
-tony
for the general public).
I did find it mildly amusing that the Facit 4070 service manual
refers to totally blank tape -- not even feed holes punched --
as 'virgin tape' ;-)
-tony
service manual and printset, I am
thinking of a theory-of-operation
manual coverting the servo, etc)
As I said, a long-term project.
-tony
of later HPs? I seem to remember they are not in the manuals). The
probe interface is also documented and quite simple. While I recomend only
getting a LA with the original pods, the ability to make custom pods has helped
me on several occasions. The inputs to both those LAs are simple differential
ECL signals, easy to hack about with.
-tony
et to without dismantling the HDA in a clean room).
-tony
>
> Hi Tony,
>
> I don't mean to throw shade on your HP 1630 or your K100 ... just in my own
> personal opinion, when I see a HP 1630 on eBay for $100 or a HP 1660 on
> eBay for $100 ... and you see this all the time ... I think going with the
Of course. And I my c
4P was luggable version, vaguely resembling early Compaq.
One incompatibilty here, the 4P has no cassette port.
Trivia question : What feature was present on all disk based M1s (in fact any
M1 with an expansion
interface) but not on any M3 or M4 machines?
-tony
>
>The double cassette ports.
Exactly. The switching relay in the expansion interface.
Did anyone ever use this feature?
> > On Jun 13, 2015, at 4:08 PM, tony duell wrote:
> >
> > Trivia question : What feature was present on all disk based M1s (in fact
>
original DELUA cable back in the rack
cabinet.
-tony
d to the chassis too.
Are there any visible screws at all? Sometimes you have to take off a thin-ish
plastic bezel or something
to reveal the real case screws.
-tony
s
that were available at the time. It's not as if a programmable buad rate
generator is hard
to make from TTL either. In fact given the Arduino thing needed 'some
debugging' it might
well have taken less time to do it in hardware.
-tony
>
> Tony, thank you for your offer to supply replacement M452 Variable Clock
> modules for the console. We already have one jumpered for 110 baud for the
> Teletype. The other two M452 modules should be jumpered for 9600 baud and
> 38400 baud. The second serial port uses a M40
ely cause I think. How long was the defective cable?
-tony
splitter cable if you want to use port B
-tony
t the FAQ suggests that pin 24
will carry a baud rate clock. Have you tried a 'scope there? If so, what do
you see, and what frequency?
-tony
e was a 100/120 flash-per-second stroboscope, the other was the transmitter
half of a modem to talk to TDDs). Both of them worked first time. I guess it's
just
what I am used to.
-tony
vintage minicomputer. How on
earth can you hope to fix a TTL-built CPU without knowing the common TTL chips
and without having a few on-hand?
-tony
the LA100 printset doesn't include the PSU schematic, the LA210 one does, and
it's the same unit again.
Totally useless coincidence that I noticed while doing a cryptic crossword :
'ethernet' is an anagram of 'three ten', and the original ethernet speeds were
three and then
ten megabits/second.
-tony
(but I suspect were never published) are a
source of the 8085 firmware in
the 11/730 and a source of the standard microcode for said machine. Oh, and a
source for the R80
firmware.
-tony
r possible use for that slot could be for my Kennedy 9610 tape
> drive. The TU80 looks like it probably
> has a Pertec interface, so I should be able to add the Kennedy drive to the
> chain to get more BPI options in the
The TS05 I have is certainly a (formatted) Pertec interface.
-tony
going
if the local oscillator had failed, or if you didn't have the right crystal, or
whatever. But I hope you wouldn't
replace the valve (tube) based local oscillator in such a set with a digital
synthesiser as a permanent 'repair'
-tony
n see if I can find the dumps. What
I don't have is the
Remote Diagnostic ROMs (this was another pair of 2K*4 ROMs that plug into
sockets on the WCS
board and which run on the 8085). So no dumps of that.
-tony
ople would rather use a microcontroller than change
a couple of passives. Can't anyone read a schematic and think
-tony
> Tony, thank you for your offer to supply replacement M452 Variable Clock
> modules for the console. We already have one jumpered for 110 baud for the
> Teletype. The other two M452 modules should be jumpered for 9600 baud and
> 38400 baud. The second serial port uses a M405 Crystal
for such things (if you do, fine). It is the classiccmp
list, where some people, including
your good self restore the actual old machines. And yes, I think it is is
reasonable to assume they will
have access to common (very common) electronic components.
-tony
appears you can change the buad rate just by changing a couple of passive
components that's what
IMHO you should do.
-tony
out as the 'packaged' system in the half-rack, and I intend to
keep it in that cabinet.
Obviously I will keep the CPU and R80, but I am not sure if the tape drive is
the most useful
third unit at this stage.
-tony
etter alternatives like the Beagleboards (?) which I need to
investigte.
This is one of my main dislikes with USB. It is so complicated that you
have to use a microcontroller. Unlike any of the more sane interfaces that
you can implement with simple logic if you want to.
-tony
rk is going to have
an effect on the output frequency. So you change the capacitor
and probe with the 'scope again. And so on.
-tony
/P
y cheap part, buy
10 of them and put the rest in stock. Or more than 10 if it is something really
common.
-tony
nally had the RL02 in it,
> then there should be no top panel, as the top-mounted RL02 was meant to be
I am not sure if I got the top panel but if I did it is no longer on the rack...
-tony
when it works (like plugging in a memory
stick) but a right pain
to debug when it doesn't. And having read the standard there is much I dislike
about it.
-tony
e things I use a lot. :)
And to get back to that darn M452 module that started this, it is _precisely_
those sort of R's and C's you need
to change its frequency!
-tony
--
Mark J. Blair, NF6X
http://www.nf6x.net/
more useful as a backup medium than the RL02...
> > I am not sure if I got the top panel but if I did it is no longer on the
> > rack...
>
> If you do have it, I wonder if it would be hard to add hinges for easy access
> to a top expansion chassis?
Something tells me that top panel was hinged at the back...
-tony
is then divided by an M216 module.
So for 110 baud (which you say you have), the M405 is running at 1760Hz? I do
not believe that for one moment!
-tony
of using just the first bytes of an SD card
> with gigabytes of storage.
Again, I wonder if the data retention time decreases as the number of bits
per device increases. Intuitively it should. Mind you, any SD card is probably
going to be more reliable than a real TU58 tape now :-)
-tony
> Sure, the pre-manufactured boards can allow you to prototype quickly... but
> I think Tony is kind of bemoaning the loss of the "old way" and I respect
> that ... I kind of miss it myself, even though I wasn't there to experience
> it first-hand ...
It'
n my partsbin?
You have to admit it would be an interesting and educational project :-)
> 'cause that is what it sounds like.
No, not really. If you have a front panel from an otherwise non-existant
machine then
it makes sense to drive it any way you can. I was thinking more of the PDP12
that started
this.
-tony
, etc, would be
interesting.
You would, of course, not know which track it was reading, so you would have to
output 2 blocks, one on
each track, at once. And how would you detect it was writing? Look for an extra
signal at the coupling head
or something?
-tony
dy characters and you can buy them.
One of the local pound shops (~= dollar stores) sells a cable with a USB A plug
on
one end and a pair of RCA phono plugs on the other. I am told this makes sense
for
some device-or-other...
Actually, IIRC a USB A male->female cable violates the spec...
-tony
[Build your own 11/70]
> Oh, very much! Then we could have a discussion about using
> modern switching power supplies ot not ;-)
As opposed to the original 11/70 switching supply?
-tony
o have one running for any longer extent I would
> consider an "upgrade". Only reversible changes of course.
Quite probably, but the modern mains-side switcher is more
troublesome and a lot less pleasant to repair. I think I'll stick
with the room-heater in my 11's :-)
-tony
n't find it that hard to basically understand in my head. After all, there
are only 4 transistors, and 2 of those are just an output buffer. Quite
why having both NPN and PNP transistors makes it harder to understand
I do not know.
I will leave the flames about Spice and simulation packages in general for
another day.
-tony
spools along with the capstan and head drum motors. No slipping
clutches. Back tension was
provided not by a light brake on the supply spool but by a suitable current
through the supply spool motor
in those machines.
-tony
more luck in getting it positioned
properly!
-tony
ape by the
relative speed of the 2 spools, this gives you the amount of tape on the takeup
spool and thus
how fast you need to turn that to get the right speed.
One of my VHS video recorders does something similar to work out how much
recording space is
left on the cassette.
-tony
:-)
It always underestimates the remaining tape (so that if it says there is 1 hour
left, you can definitely fit
a 1 hour TV programme on there). But it is suprisingly good.
-tony
acteristics (e.g. using it as a ballast resistor),
so no kludge with a CFL is likely to work
-tony
t a
line printer at all) has a belt
running across the chassis with a motor continuously driving it (a shaded pole
motor I think). Solenoids
on the printhead carriage grab the top or bottom run of the belt depending on
which way the carriage
is to move.
-tony
rode. The toner
doesn't all end up
on the electrode, some goes on the paper. Or at least that#s the idea. Setting
one up is an interesting
job (I turned a pointed pin to make things a little easier) and the quality is
non-existant even when it is
working properly.
-tony
ety component' warning telling you only to use
the parts specified in the service manual on the back cover. But I was totally
unable to obtain said service manual.
-tony
the demise of the paper databook, you simply can't buy them any more. Oh
well...
FWIW, I must have over 100 databooks here. Mostly mid 1980s - 1990, but a
few earlier.
-tony
l (this assumes
the simulator gets it right which is not always the case). I prefer to think
about
it. work out how the capacitor (there is only one!) charges and discharges,
since
that must be the key to the oscillations.
-tony
jump to
100kHz
and up. So I woulg guess the original design was to use an M405 and another
module
(perhaps another M216) as a divider.
-tony
--
Michael Thompson
urface to position the heads and
reformat the fixed disk data surfaces.
-tony
Johnny
>
> /P
>
> On Wed, Jun 17, 2015 at 11:39:25AM -0400, Noel Chiappa wrote:
>> Anyone need an RK06 alignment pack:
>>
>>
>> http://www.ebay.com/itm/Digital-Equi
n reformat
such a disk.
No the procedure I was thinking of was to re-write the dedicated servo surface
on the fixed
disk stack of a fixed/removeable drive that used a servo signal from the disk.
I am pretty sure
it was an HP drive, maybe the 7905 or 7906 (I don't have either).
-tony
mean classic computers
;-)
> have paper... When I'm doing a project, most of my schematics start out on
> scraps of paper, too :O
That's all I ever use (well, maybe not scraps...). I call it a 'Paper Aided
Design' system,
aka a 'PAD'.
-tony
meter, not a 'scope. And that there are special tools for moving the heads
I found a sort-of user manual for this on bitsavers, but no schematics of the
meter, so no easy way to replicate it.
-tony
o you can fit them round the
cable after wiring, thus avoiding the fruity language normally produced when
you wire up nearly 100 wires and realise you have forgotten to thread the cable
through the back shell.
-tony
guess they're formatted for a PDP8 system, but I
can't be sure. I have
never had the time to get it all working...
[1] No, not a TU55. This is a TU56 with just one transport and a blanking plate
over the other holes, It is
an official DEC variant.
Where are you in the UK? I am wondering if I have to trust ParcelFarce with
them...
-tony
of those.
Does anyone recognise this board?
A related point, I am thinking of removing the TSU05 from my 11/730 and putting
an expansion
box in place of the tape drive in the rack. In which case I can install this
memory board. Is 5MBytes
(the maximum an 11/730 can take) worth having over 4MBytes?
-tony
t to do this I do
not know...
Oh, and it mentions a 'spare RAM chip in a socket on the board'. All RAM on my
board is, indeed, socketed.
If this is just an unused chip to substitute if one fails then I think I've
seen it all...
-tony
t in the half-rack, so
I would have to remove the TS05
drive to have somewhere to fit the expanison box. In any case the TSU05 could
go in said expansion box if
I ever need it, I think.
My TS05 needs a bit of work to get it going, and I do wonder how useful it
would be. Any comments?
-tony
Like this one? http://www.ebay.com/itm/Wright-Punch-Model-2600-/331580084313
I'm not sure it really needs a manual. I repaired one with a careful
disassemble and cleaning. On mine, the cord linking the tension spring to
the mechanism had broken. A trip to the hardware store found something
similar
to have a MOS device with all inputs floating? I would have
thought it would have been
better to tie eveything (including the +5V pin) to ground, or to power the RAM
but have pull-up resistors
on all the inputs.
-tony
grabbed
that.
But a lot of my finds came to me before they were thrown out. I was known for
wanting just about any old electronic or computer gear.
-tony
s to all the
memory boards, at least
in the 11/730. And I know the machine will not behave normally if there are
gaps in the physical memory
space, quite whether it would run diagnostics in that case I do not know. So I
guess you had better have all
the DEC boards at the start of the memory space and if you want to make the 3rd
party RAM disappear,
disable all the boards.
-tony
nd
> one at the end?
If it's any help I pulled an M9014 out of the Unibus Out slot of my 11/730.
There's currently an
M9302 in there. I can't find the original expansion box (yet) so I have no idea
what was on the other
end of the cables.
-tony
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