[pups] PDP-11 / vacuum tube interface

[pups] PDP-11 / vacuum tube interface

[Fred N. van Kempen]

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I was bored, and ported my version of SimH (which is an older
version, but with some stuff ripped out, and other stuff put
in) to my operating system for my ARM-based MCU board.  It
now "acts" like a regular 11/83 when turned on, and will
happily boot Ultrix-11 off the CF card :)

Not as fast as running on a peecee, not half as much fun as
running a real '11, but hey, it DOES fit into my backpack.

--f 

-----Original Message-----
From: pups-bounces@minnie.tuhs.org [mailto:pups-bounces@minnie.tuhs.org] On Behalf Of Jochen Kunz
Sent: Thursday, December 11, 2008 6:15 PM
To: pups at minnie.tuhs.org
Subject: Re: [pups] PDP-11 / vacuum tube interface

On Wed, 10 Dec 2008 19:09:34 +0100
"Fred N. van Kempen" <fred.van.kempen at microwalt.nl> wrote:

> smiling @ his nano-11 system running Ultrix, all the size of
>       a matchbox..
nano-11? Please elaborate.
-- 


tschüß,
       Jochen

Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/

_______________________________________________
PUPS mailing list
PUPS at minnie.tuhs.org
https://minnie.tuhs.org/mailman/listinfo/pups

[pups] PDP-11 / vacuum tube interface

[Gregg C Levine]

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Hello!
The term is Trekker, Kevin. And it takes place during the second act of a
very important episode. 


But I freely admit that I am interested in this decidedly strange mix of
technology.
--
Gregg C Levine hansolofalcon at worldnet.att.net
"The Force will be with you always." Obi-Wan Kenobi
  


> -----Original Message-----
> From: pups-bounces at minnie.tuhs.org [mailto:pups-bounces at minnie.tuhs.org]
On Behalf
> Of Kevin McQuiggin
> Sent: Wednesday, December 10, 2008 7:04 PM
> To: Bill Gunshannon
> Cc: pups at minnie.tuhs.org
> Subject: Re: [pups] PDP-11 / vacuum tube interface
> 
> One could always build "a mnemonic memory circuit using stone knives
> and bearskins"...
> 
> For those Trekkies out there...
> 
> Kevin
> 
> On 10-Dec-08, at 1:25 PM, Bill Gunshannon wrote:
> 
> >
> > If the intent was to be the first one to wed computers and vacuum
> > tubes,
> > you have missed the boat by several decades.  I, and I am sure many
> > others
> > did it long ago.  I ran HF AX.25 Packet Radio on my Heathkit HW-101.
> >
> > Of course, if the desire is to wed the PDP-11 and vacuum tubes, if it
> > hasn't been done already the same could be done.  I would bet I could
> > put an old version of the KA9Q software on a PDP-11 running BSD or
> > even
> > Ultrix-11.  And then, fire up my HW-101 (yes, I still have it) and the
> > deed is done.  Of course, I could also use my HF rig which is also of
> > the vacuum tube genre.  Drake Twins. :-)
> >
> > bill
> >
> > --
> > Bill Gunshannon          |  de-moc-ra-cy (di mok' ra see) n.  Three
> > wolves
> > bill at cs.scranton.edu     |  and a sheep voting on what's for dinner.
> > University of Scranton   |
> > Scranton, Pennsylvania   |         #include <std.disclaimer.h>
> >
> >
> > _______________________________________________
> > PUPS mailing list
> > PUPS at minnie.tuhs.org
> > https://minnie.tuhs.org/mailman/listinfo/pups
> >
> 
> _______________________________________________
> PUPS mailing list
> PUPS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/pups

[pups] PDP-11 / vacuum tube interface

[Jochen Kunz]

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On Wed, 10 Dec 2008 19:09:34 +0100
"Fred N. van Kempen" <fred.van.kempen at microwalt.nl> wrote:

> smiling @ his nano-11 system running Ultrix, all the size of
>       a matchbox..
nano-11? Please elaborate.
-- 


tschüß,
       Jochen

Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/

[pups] PDP-11 / vacuum tube interface

[Ian King]

But only if you have Joan Collins to inspire you.

> -----Original Message-----
> From: pups-bounces at minnie.tuhs.org [mailto:pups-
> bounces at minnie.tuhs.org] On Behalf Of Kevin McQuiggin
> Sent: Wednesday, December 10, 2008 4:04 PM
> To: Bill Gunshannon
> Cc: pups at minnie.tuhs.org
> Subject: Re: [pups] PDP-11 / vacuum tube interface
>
> One could always build "a mnemonic memory circuit using stone knives
> and bearskins"...
>
> For those Trekkies out there...
>
> Kevin
>
> On 10-Dec-08, at 1:25 PM, Bill Gunshannon wrote:
>
> >
> > If the intent was to be the first one to wed computers and vacuum
> > tubes,
> > you have missed the boat by several decades.  I, and I am sure many
> > others
> > did it long ago.  I ran HF AX.25 Packet Radio on my Heathkit HW-101.
> >
> > Of course, if the desire is to wed the PDP-11 and vacuum tubes, if it
> > hasn't been done already the same could be done.  I would bet I could
> > put an old version of the KA9Q software on a PDP-11 running BSD or
> > even
> > Ultrix-11.  And then, fire up my HW-101 (yes, I still have it) and
> the
> > deed is done.  Of course, I could also use my HF rig which is also of
> > the vacuum tube genre.  Drake Twins. :-)
> >
> > bill
> >
> > --
> > Bill Gunshannon          |  de-moc-ra-cy (di mok' ra see) n.  Three
> > wolves
> > bill at cs.scranton.edu     |  and a sheep voting on what's for dinner.
> > University of Scranton   |
> > Scranton, Pennsylvania   |         #include <std.disclaimer.h>
> >
> >
> > _______________________________________________
> > PUPS mailing list
> > PUPS at minnie.tuhs.org
> > https://minnie.tuhs.org/mailman/listinfo/pups
> >
>
> _______________________________________________
> PUPS mailing list
> PUPS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/pups

[pups] PDP-11 / vacuum tube interface

[Kevin McQuiggin]

One could always build "a mnemonic memory circuit using stone knives  
and bearskins"...

For those Trekkies out there...

Kevin

On 10-Dec-08, at 1:25 PM, Bill Gunshannon wrote:

>
> If the intent was to be the first one to wed computers and vacuum  
> tubes,
> you have missed the boat by several decades.  I, and I am sure many  
> others
> did it long ago.  I ran HF AX.25 Packet Radio on my Heathkit HW-101.
>
> Of course, if the desire is to wed the PDP-11 and vacuum tubes, if it
> hasn't been done already the same could be done.  I would bet I could
> put an old version of the KA9Q software on a PDP-11 running BSD or  
> even
> Ultrix-11.  And then, fire up my HW-101 (yes, I still have it) and the
> deed is done.  Of course, I could also use my HF rig which is also of
> the vacuum tube genre.  Drake Twins. :-)
>
> bill
>
> -- 
> Bill Gunshannon          |  de-moc-ra-cy (di mok' ra see) n.  Three  
> wolves
> bill at cs.scranton.edu     |  and a sheep voting on what's for dinner.
> University of Scranton   |
> Scranton, Pennsylvania   |         #include <std.disclaimer.h>
>
>
> _______________________________________________
> PUPS mailing list
> PUPS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/pups
>

[pups] PDP-11 / vacuum tube interface

[Bill Gunshannon]

If the intent was to be the first one to wed computers and vacuum tubes,
you have missed the boat by several decades.  I, and I am sure many others
did it long ago.  I ran HF AX.25 Packet Radio on my Heathkit HW-101.

Of course, if the desire is to wed the PDP-11 and vacuum tubes, if it
hasn't been done already the same could be done.  I would bet I could
put an old version of the KA9Q software on a PDP-11 running BSD or even
Ultrix-11.  And then, fire up my HW-101 (yes, I still have it) and the
deed is done.  Of course, I could also use my HF rig which is also of
the vacuum tube genre.  Drake Twins. :-)

bill

-- 
Bill Gunshannon          |  de-moc-ra-cy (di mok' ra see) n.  Three wolves
bill at cs.scranton.edu     |  and a sheep voting on what's for dinner.
University of Scranton   |
Scranton, Pennsylvania   |         #include <std.disclaimer.h>

[pups] PDP-11 / vacuum tube interface

[Fred N. van Kempen]

> (This has got to be the strangest cross-post I've ever done.)
You've got that right :P

> I do sincerely apologize for
> cross-posting, but I am rather younger than either of these
> technologies (vintage: 1984) and this seems like a monumental
> challenge.
Well, several projects can be thought off in this scenario, but
if you want to keep it mildly useful, try to do something with
audio tubes connected to an '11 (OK, here's a spoiler: "you'll
make a PDP11-driven music player using a tube-based audio
backend"), or such.  You could go into analog computing as
well, but that can be kinda hairy.

This more or less only requires building a usable D/A converter
on the '11, which then interfaces to the tubes.  I'd use a DMA-
based 16-bit DA controller.

Cheers,

Fred (smiling @ his nano-11 system running Ultrix, all the size of
      a matchbox..)

[pups] PDP-11 / vacuum tube interface

[Jochen Kunz]

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On Tue, 9 Dec 2008 17:00:32 -0700
"Ross Tucker" <rjtucke at gmail.com> wrote:

> Does anybody know if PDP-11 UNIXes even had the capability for a
> "sound card"?
There are ADC cards for QBus (and most likely UniBUS) PDP-11s...
What about PSK31? QRSS?
-- 


tschüß,
       Jochen

Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/

[pups] PDP-11 / vacuum tube interface

[robinb]

That's a wonderful idea.  As has been pointed out there are a number of A2D and D2A boards available for the PDP11.  However it would be fun to do it yourself and design one from scratch although getting hold of prototyping boards for unibus or Q bus could be a bit difficult these days.

You would probably have to down convert your RF to audio to keep everything in the realm of what the PDP could handle though something like PSK should be able to be resolved, morse should be a doddle.

Have a go, this is seriously pointless geeky stuff and as a result huge fun.

Robin

rjtucke at gmail.com wrote:
> Dear all,
> (This has got to be the strangest cross-post I've ever done.)
> 
> I have just taken a bet from a friend to challenge my geekiness. I was
> telling him about my love of Vintage Technology and he proposed that I
> combine two hitherto separate hobbies and see what happens. The
> topics: the DEC PDP-11 minicomputer (vintage: 1970s) and vacuum-tube
> ham radios (vintage: 1960s). I do sincerely apologize for
> cross-posting, but I am rather younger than either of these
> technologies (vintage: 1984) and this seems like a monumental
> challenge.
> 
> My question for y'all: how could I possibly design+build a project
> that uses both of these technologies? My thought is to port some radio
> receiver Digital Signal Processing (DSP) application into PDP-11
> assembler, compile and run it via emulator on my PC, then use it with
> the vacuum-tube regenerative receiver that I built a few years ago...
> Does anybody know if PDP-11 UNIXes even had the capability for a
> "sound card"? Or, to get ambitious, I would LOVE to design some
> interface circuitry between PDP-11 digital circuitry and vacuum-tube
> electronics... The challenges are legion: the tube side of the circuit
> operates around 350V DC levels with radio-frequency (RF) signals at 7
> MHz (almost the clock rate of some PDP-11s!) and I don't have the DEC
> Handbooks, but I'm pretty sure that even those ancient pre-TTL
> circuits operate below 350V!
> 
> So... any, er, "ideas"?
> 
> Best regards,
> Ross Tucker
> _______________________________________________
> PUPS mailing list
> PUPS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/pups
> 

[pups] PDP-11 / vacuum tube interface

[Kevin McQuiggin]

How about using the pdp-11 to decode Morse code transmissions that you  
receive on your vintage radio?  This would eliminate any issues with  
interfacing to HV circuits, as you could simply run the radio's audio  
output through a PLL circuit to detect tone/no tone and then read this  
single bit signal on the pdp-11.  You decode the Morse code in  
software.  I have code for you (in an old version of Pascal) if you'd  
like.  It adapts to the Morse code speed automatically and "catches  
up" to changes in Morse speed in about 5 letters maximum, as I  
recall.  From an undergrad project I completed in the late 1970s!  I  
could also dig out the hardware info.  Then again you might have more  
fun reinventing this yourself!

Kevin

On 9-Dec-08, at 4:00 PM, Ross Tucker wrote:

> Dear all,
> (This has got to be the strangest cross-post I've ever done.)
>
> I have just taken a bet from a friend to challenge my geekiness. I was
> telling him about my love of Vintage Technology and he proposed that I
> combine two hitherto separate hobbies and see what happens. The
> topics: the DEC PDP-11 minicomputer (vintage: 1970s) and vacuum-tube
> ham radios (vintage: 1960s). I do sincerely apologize for
> cross-posting, but I am rather younger than either of these
> technologies (vintage: 1984) and this seems like a monumental
> challenge.
>
> My question for y'all: how could I possibly design+build a project
> that uses both of these technologies? My thought is to port some radio
> receiver Digital Signal Processing (DSP) application into PDP-11
> assembler, compile and run it via emulator on my PC, then use it with
> the vacuum-tube regenerative receiver that I built a few years ago...
> Does anybody know if PDP-11 UNIXes even had the capability for a
> "sound card"? Or, to get ambitious, I would LOVE to design some
> interface circuitry between PDP-11 digital circuitry and vacuum-tube
> electronics... The challenges are legion: the tube side of the circuit
> operates around 350V DC levels with radio-frequency (RF) signals at 7
> MHz (almost the clock rate of some PDP-11s!) and I don't have the DEC
> Handbooks, but I'm pretty sure that even those ancient pre-TTL
> circuits operate below 350V!
>
> So... any, er, "ideas"?
>
> Best regards,
> Ross Tucker
> _______________________________________________
> PUPS mailing list
> PUPS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/pups
>

[pups] PDP-11 / vacuum tube interface

[Ian King]

In addition to the DECtalk standalone device, there was a Qbus module called DECVoice (DTC04) that was intended for telephone systems (voice response systems).  I have the module in my personal collection; unfortunately, what I've been told is that there's a lot of others' intellectual property in the software (it's a microcoded device) so it would be a serious challenge to get the code to run it - too bad.  -- Ian
________________________________________
From: pups-bounces@minnie.tuhs.org [pups-bounces@minnie.tuhs.org] On Behalf Of Ross Tucker [rjtucke@gmail.com]
Sent: Tuesday, December 09, 2008 6:49 PM
To: pups at minnie.tuhs.org
Subject: [pups] PDP-11 / vacuum tube interface

Dear all,
(This has got to be the strangest cross-post I've ever done.)

I have just taken a bet from a friend to challenge my geekiness. I was
telling him about my love of Vintage Technology and he proposed that I
combine two hitherto separate hobbies and see what happens. The
topics: the DEC PDP-11 minicomputer (vintage: 1970s) and vacuum-tube
ham radios (vintage: 1960s). I do sincerely apologize for
cross-posting, but I am rather younger than either of these
technologies (vintage: 1984) and this seems like a monumental
challenge.

My question for y'all: how could I possibly design+build a project
that uses both of these technologies? My thought is to port some radio
receiver Digital Signal Processing (DSP) application into PDP-11
assembler, compile and run it via emulator on my PC, then use it with
the vacuum-tube regenerative receiver that I built a few years ago...
Does anybody know if PDP-11 UNIXes even had the capability for a
"sound card"? Or, to get ambitious, I would LOVE to design some
interface circuitry between PDP-11 digital circuitry and vacuum-tube
electronics... The challenges are legion: the tube side of the circuit
operates around 350V DC levels with radio-frequency (RF) signals at 7
MHz (almost the clock rate of some PDP-11s!) and I don't have the DEC
Handbooks, but I'm pretty sure that even those ancient pre-TTL
circuits operate below 350V!

So... any, er, "ideas"?

Best regards,
Ross Tucker

CCed to: 'glowbugs' list at <glowbugs at piobaire.mines.uidaho.edu>
_______________________________________________
PUPS mailing list
PUPS at minnie.tuhs.org
https://minnie.tuhs.org/mailman/listinfo/pups

[pups] PDP-11 / vacuum tube interface

[Ross Tucker]

Dear all,
(This has got to be the strangest cross-post I've ever done.)

I have just taken a bet from a friend to challenge my geekiness. I was
telling him about my love of Vintage Technology and he proposed that I
combine two hitherto separate hobbies and see what happens. The
topics: the DEC PDP-11 minicomputer (vintage: 1970s) and vacuum-tube
ham radios (vintage: 1960s). I do sincerely apologize for
cross-posting, but I am rather younger than either of these
technologies (vintage: 1984) and this seems like a monumental
challenge.

My question for y'all: how could I possibly design+build a project
that uses both of these technologies? My thought is to port some radio
receiver Digital Signal Processing (DSP) application into PDP-11
assembler, compile and run it via emulator on my PC, then use it with
the vacuum-tube regenerative receiver that I built a few years ago...
Does anybody know if PDP-11 UNIXes even had the capability for a
"sound card"? Or, to get ambitious, I would LOVE to design some
interface circuitry between PDP-11 digital circuitry and vacuum-tube
electronics... The challenges are legion: the tube side of the circuit
operates around 350V DC levels with radio-frequency (RF) signals at 7
MHz (almost the clock rate of some PDP-11s!) and I don't have the DEC
Handbooks, but I'm pretty sure that even those ancient pre-TTL
circuits operate below 350V!

So... any, er, "ideas"?

Best regards,
Ross Tucker

CCed to: 'glowbugs' list at <glowbugs at piobaire.mines.uidaho.edu>

[pups] PDP-11 / vacuum tube interface

[Jay Jaeger]

Back in the 1970's Paul Pierce used a D/A converter on a PDP-11 at the UW 
Computer Systems Lab to generate music much like early PC sound cards did 
-- by combining harmonics in various ratios.  Although he happened to have 
used RT-11, there is no reason why it could not be done under Unix.  (The 
UW Computer Systems Lab also had a Votrax).

So, sure, you could, with an A/D and D/A converter do something like 
that.  I am not sure that the various emulators have done emulation for A/D 
or D/A, but in principle, it ought to be possible.

AC coupling (via a capacitor) of the input or output would remove any 
concerns about the relatively high DC voltages.  Besides, input signals 
ordinarily come into the grids of vacuum tube circuits by way of a 
transformer.  Ditto for outputs from tube circuits.

Jay Jaeger


At 05:37 PM 12/9/2008 -0800, Carl Lowenstein wrote:
>On Tue, Dec 9, 2008 at 4:00 PM, Ross Tucker <rjtucke at gmail.com> wrote:
> > Dear all,
> > (This has got to be the strangest cross-post I've ever done.)
> >
> > I have just taken a bet from a friend to challenge my geekiness. I was
> > telling him about my love of Vintage Technology and he proposed that I
> > combine two hitherto separate hobbies and see what happens. The
> > topics: the DEC PDP-11 minicomputer (vintage: 1970s) and vacuum-tube
> > ham radios (vintage: 1960s). I do sincerely apologize for
> > cross-posting, but I am rather younger than either of these
> > technologies (vintage: 1984) and this seems like a monumental
> > challenge.
> >
> > My question for y'all: how could I possibly design+build a project
> > that uses both of these technologies? My thought is to port some radio
> > receiver Digital Signal Processing (DSP) application into PDP-11
> > assembler, compile and run it via emulator on my PC, then use it with
> > the vacuum-tube regenerative receiver that I built a few years ago...
> > Does anybody know if PDP-11 UNIXes even had the capability for a
> > "sound card"?
>
>Well, you could look at "Votrax" on Wikipedia.  Allegedly, the first
>words spoken by a Unix system at Bell Labs, using its Votrax
>synthesizer, were "file not found".
>
>Things that are now known as "sound cards" were called A:D and D:A
>converters back in those days.  And there were a fair variety of them
>available for both Unibus and Qbus systems.
>
> > Or, to get ambitious, I would LOVE to design some
> > interface circuitry between PDP-11 digital circuitry and vacuum-tube
> > electronics... The challenges are legion: the tube side of the circuit
> > operates around 350V DC levels with radio-frequency (RF) signals at 7
> > MHz (almost the clock rate of some PDP-11s!) and I don't have the DEC
> > Handbooks, but I'm pretty sure that even those ancient pre-TTL
> > circuits operate below 350V!
>
>The vacuum-tube circuits may be running from 350 VDC but somewhere
>there are low-level inputs from which everything is amplified.  Think
>microphone.
>
>     carl
>--
>     carl lowenstein         marine physical lab     u.c. san diego
>                                                  clowenstein at ucsd.edu
>_______________________________________________
>PUPS mailing list
>PUPS at minnie.tuhs.org
>https://minnie.tuhs.org/mailman/listinfo/pups

---	
Jay R. Jaeger					The Computer Collection
cube1 at charter.net

[pups] PDP-11 / vacuum tube interface

[Carl Lowenstein]

On Tue, Dec 9, 2008 at 4:00 PM, Ross Tucker <rjtucke at gmail.com> wrote:
> Dear all,
> (This has got to be the strangest cross-post I've ever done.)
>
> I have just taken a bet from a friend to challenge my geekiness. I was
> telling him about my love of Vintage Technology and he proposed that I
> combine two hitherto separate hobbies and see what happens. The
> topics: the DEC PDP-11 minicomputer (vintage: 1970s) and vacuum-tube
> ham radios (vintage: 1960s). I do sincerely apologize for
> cross-posting, but I am rather younger than either of these
> technologies (vintage: 1984) and this seems like a monumental
> challenge.
>
> My question for y'all: how could I possibly design+build a project
> that uses both of these technologies? My thought is to port some radio
> receiver Digital Signal Processing (DSP) application into PDP-11
> assembler, compile and run it via emulator on my PC, then use it with
> the vacuum-tube regenerative receiver that I built a few years ago...
> Does anybody know if PDP-11 UNIXes even had the capability for a
> "sound card"?

Well, you could look at "Votrax" on Wikipedia.  Allegedly, the first
words spoken by a Unix system at Bell Labs, using its Votrax
synthesizer, were "file not found".

Things that are now known as "sound cards" were called A:D and D:A
converters back in those days.  And there were a fair variety of them
available for both Unibus and Qbus systems.

> Or, to get ambitious, I would LOVE to design some
> interface circuitry between PDP-11 digital circuitry and vacuum-tube
> electronics... The challenges are legion: the tube side of the circuit
> operates around 350V DC levels with radio-frequency (RF) signals at 7
> MHz (almost the clock rate of some PDP-11s!) and I don't have the DEC
> Handbooks, but I'm pretty sure that even those ancient pre-TTL
> circuits operate below 350V!

The vacuum-tube circuits may be running from 350 VDC but somewhere
there are low-level inputs from which everything is amplified.  Think
microphone.

    carl
-- 
    carl lowenstein         marine physical lab     u.c. san diego
                                                 clowenstein at ucsd.edu

[pups] PDP-11 / vacuum tube interface

[Ross Tucker]

Dear all,
(This has got to be the strangest cross-post I've ever done.)

I have just taken a bet from a friend to challenge my geekiness. I was
telling him about my love of Vintage Technology and he proposed that I
combine two hitherto separate hobbies and see what happens. The
topics: the DEC PDP-11 minicomputer (vintage: 1970s) and vacuum-tube
ham radios (vintage: 1960s). I do sincerely apologize for
cross-posting, but I am rather younger than either of these
technologies (vintage: 1984) and this seems like a monumental
challenge.

My question for y'all: how could I possibly design+build a project
that uses both of these technologies? My thought is to port some radio
receiver Digital Signal Processing (DSP) application into PDP-11
assembler, compile and run it via emulator on my PC, then use it with
the vacuum-tube regenerative receiver that I built a few years ago...
Does anybody know if PDP-11 UNIXes even had the capability for a
"sound card"? Or, to get ambitious, I would LOVE to design some
interface circuitry between PDP-11 digital circuitry and vacuum-tube
electronics... The challenges are legion: the tube side of the circuit
operates around 350V DC levels with radio-frequency (RF) signals at 7
MHz (almost the clock rate of some PDP-11s!) and I don't have the DEC
Handbooks, but I'm pretty sure that even those ancient pre-TTL
circuits operate below 350V!

So... any, er, "ideas"?

Best regards,
Ross Tucker