[9fans] Old (hardware) are hard to break

[9fans] Old (hardware) are hard to break

[northern snowfall]

Hey all,
	I picked up a HP Apollo PA-RISC 1.1 workstation
at UMich recently. I just simply could not pass up the
opportunity to snag this machine for $25. I only have
one problem. The workstation is in Graphic mode and
expects a 3BNC monitor and a HIL keyboard attached in
order to access the boot prom. Once in boot prom, I
can alter boot conditions to switch over to the
serial console.
	I expected to find these items at my local
universities, knowing most of the sysadmins around
town. Unfortunately, I'm finding that these small Unis
have bailed on this hardware. Recently.
	Does anyone have access to this hardware and
want to throw it to someone that will actually use
and study it? If so, email me privately.

Have car, will drive
Don

P.S. The website will be back up soon. Yes the projects
haven't stopped progressing. Thanks for your emails
and queries regarding updates.

http://www.7f.no-ip.com/~north_

Re: [9fans] Old (hardware) are hard to break

[northern snowfall]

> Have car, will drive

Woo hoo! Got the Apollo booting into serial console
mode. Now for the step of attaching the Thinnet card
to my 100baseT network. Does anyone know how to
do this or can point me to a link where I can find
the proper information? Google has not been my friend
to{day,night} (Pike, I'm looking at you ;-)). Then
again, it could be because I've been auditing and
tweaking network stacks all night... guh!@!$^

Don

http://www.7f.no-ip.com/~north_

FAI the web site is down while i recode the NetBSD kernel.

Re: [9fans] Old (hardware) are hard to break

[northern snowfall]

> Does anyone know how to
> do this or can point me to a link where I can find
> the proper information?


Hah, finally. Ok, I think I have this figured out. It
looks like the simplest thing to do is to use a T
connector (which I have (thanks zgs)).

The T connector connects to the BNC on the Thinnet card.

The cable from the T connector has an AUI endpoint,
which connects to an AUI adapter.

The AUI adapter is like my Asante AUI->10baseT adapter
(thanks again, zgs), which converts the connection to
10baseT.

Am I missing anything?
Do I need to cap the naked side of the T connector in
some fashion?

All these questions, and more, I hope to have answered by
*you* guys! The people with all the experience!!! :-)

Don

http://www.7f.no-ip.com/~north_

FAI the web site is down while i recode the NetBSD kernel.

Re: [9fans] Old (hardware) are hard to break

[Jim Choate]

On Fri, 12 Sep 2003, northern snowfall wrote:

> Am I missing anything?
> Do I need to cap the naked side of the T connector in
> some fashion?

Yes, you will need to terminate the connection. You should normally have a
T at both ends of the cable and a terminator should be on both of them.
You shouldn't just plug the cable onto the BNC connector.

 -- --
      ravage@ssz.com                            jchoate@open-forge.com
      www.ssz.com                               www.open-forge.com

Re: [9fans] Old (hardware) are hard to break

[ron minnich]

On Fri, 12 Sep 2003, northern snowfall wrote:

> Do I need to cap the naked side of the T connector in
> some fashion?

you need a 50-ohm terminator on the empty side, or the electrons will leak
out, fall on the floor, and fill the room up, and then you won't be able
to breath.

ron

Re: [9fans] Old (hardware) are hard to break

[northern snowfall]

>
>
>you need a 50-ohm terminator on the empty side
>

Well, I'm not cleaning this floor every few minutes to manage the
electron spill, so I'd better get the terminator. I don't think my
mop can handle electrons, anyway....

I found a place that sells 50ohm BNC -> 10baseT adapters online,
but I do have one last question. Do i *need* a cable connecting the
T to the BNC? I'm sure this is probably desirable, but is it
absolutely necessary? I'm just trying to minimize the connections.

Also, is the cable that I need a patch cable? I'm assuming yes.

Thanks for all the tips, guys. I really appreciate this.

Don

http://www.7f.no-ip.com/~north_

FAI the web site is down while i recode the NetBSD kernel.

Re: [9fans] Old (hardware) are hard to break

[boyd, rounin]

> Well, I'm not cleaning this floor every few minutes to manage the
> electron spill, so I'd better get the terminator. I don't think my
> mop can handle electrons, anyway....

they won't spill.  you'll wind up with a nasty SWR problem.

coax must alway be terminated correctly, so chain things together
you stick a T connector on each machine and at the ends of the
coax you screw on 50 ohm terminators.  i have seen bad things
happen with unterminated coax.

> I found a place that sells 50ohm BNC -> 10baseT adapters online,
> but I do have one last question. Do i *need* a cable connecting the
> T to the BNC? I'm sure this is probably desirable, but is it
> absolutely necessary? I'm just trying to minimize the connections.

i'm a bit confused, but read what i said above.  you got a URL for
the adapter?

Re: [9fans] Old (hardware) are hard to break

[northern snowfall]

>
>
>i'm a bit confused, but read what i said above.  you got a URL for
>the adapter?
>
Yes sir, I do.

http://www.pacificcable.com/Picture_Page.asp?DataName=BA2

As you can see, the BNC connector is a Male. The T, of course, has
female connectors on the arms of the T. That's why I wondered if
it was ok to connect the BNC adapter directly onto an arm of the T.

Don

http://www.7f.no-ip.com/~north_

FAI the web site is down while i recode the NetBSD kernel.

>

Re: [9fans] Old (hardware) are hard to break

[boyd, rounin]

> As you can see, the BNC connector is a Male. The T, of course, has
> female connectors on the arms of the T. That's why I wondered if
> it was ok to connect the BNC adapter directly onto an arm of the T.

i see.  stick the adapter on the T and termininator on the other side of the T.

you remember the vampire taps on think ethernet?  sam principle.  it
was coax too, but high grade stuff, who name i forget, bu you're using
RG-58 [50 ohms].  the high grade stuff had N connectors on the ends
and was used for high [UHF/SHF] freq, high power and was low loss.

iirc RG-58 losses are 3db/100m.  it's good for VHF [< 300Mhz] but
not so hot for UHF [> 300Mhz].

the high grade stuff was chosen for 1km 'rings'.

you can see i wasted/spent a lotta time with radio stuff.

Re: [9fans] Old (hardware) are hard to break

[Dan Cross]

> > As you can see, the BNC connector is a Male. The T, of course, has
> > female connectors on the arms of the T. That's why I wondered if
> > it was ok to connect the BNC adapter directly onto an arm of the T.
>
> i see.  stick the adapter on the T and termininator on the other side of the T.

Yes, what Boyd said.  Stick a T onto the adapater (the base, the female
part, goes onto it), and a terminator onto one side, and a piece of RG-58
coax on the other.  Connect the other end of the coax to a T connected to
your ethernet adapter, and stick another terminator on the other side of
that T.  *Both* sides must be properly terminated with a 50-Ohm resister
pack (which is what a terminator is) in order to prevent signal reflection
on the cable, hence the need for two terminators and two T's at the ends
of the network.  Also, be careful with media converters; make sure you
get the power needs right.  In general, I try to avoid converters and
instead would get an old hub with both a 10Base-2 connector and some
10Base-T ports, and then run a cross-over cable (UTP) from that to
your main hub or switch or whatever you've got.

> you remember the vampire taps on think ethernet?  sam principle.  it
> was coax too, but high grade stuff, who name i forget, bu you're using
> RG-58 [50 ohms].  the high grade stuff had N connectors on the ends
> and was used for high [UHF/SHF] freq, high power and was low loss.

I imagine that was probably a bit before his time, but that was RG-1
coax, if I'm not mistaken.  It also has a characteristic impedence of
50 Ohms.

	- Dan C.

Re: [9fans] Old (hardware) are hard to break

[ron minnich]

On Fri, 12 Sep 2003, northern snowfall wrote:

> I found a place that sells 50ohm BNC -> 10baseT adapters online,
> but I do have one last question. Do i *need* a cable connecting the
> T to the BNC? I'm sure this is probably desirable, but is it
> absolutely necessary? I'm just trying to minimize the connections.

the T should go right on the bnc on the back of the apollo. Then you
connect a cable to one side, and a cable or 50ohm to the other side.

ron