Re: That Tek 405x QIC Tape.

2017-10-04 Thread Christian Corti via cctalk

On Tue, 3 Oct 2017, Al Kossow wrote:
As far as I know, no one has successfully made a copy of a Tek cartridge 
tape in an image format. The tapes use two tracks, one for clock and one 
for data. Encoding beyond that has not been determined. I still have


I can backup Tek405x tapes. Our 4051 has a very featurerich ROM extension 
called COMBI ROM and a RAM back pack used to load the COMBI ROM from tape 
into RAM and use that as an extension ROM.
This COMBI ROM can not only access tape records directly (they are 256 
bytes records), but it also handles CBM floppy disk drives (e.g. 8050) 
attached to the GPIB.
I've written a BASIC program that reads all tape files and stores them 1:1 
as disk files on a floppy. This is not truly the same as imaging a tape 
cartridge, but it is better than nothing ;-) AFAIK there is no additional 
metadata other than the tape file header (read with CALL "HEADER", 
file number [,header string]). The tape records are read with CALL 
"TREAD", string variable.


Christian


Re: That Tek 405x QIC Tape.

2017-10-03 Thread Al Kossow via cctalk


On 10/3/17 8:29 AM, Mike Stein via cctalk wrote:

> Sounds like a similar system to what Burroughs used on their cassettes; I 
> always thought that they'd be a lot easier to read than the 'normal' formats 
> with embedded clock signals and always intended to try to read some of the 
> tapes I have here some day. 
> 
> May have to move it up a few pages of my to-do list now that you've reminded 
> me, although I doubt that there's much interest 'out there' in 'L' series 
> software...

it would be good to get it archived.

reminds me I have a box of B1900 cold start tapes and a couple of cassette 
drives I should do something with :-(




Re: That Tek 405x QIC Tape.

2017-10-03 Thread Mike Stein via cctalk

- Original Message - 
From: "Al Kossow via cctalk" <cctalk@classiccmp.org>
To: <cctalk@classiccmp.org>
Sent: Tuesday, October 03, 2017 11:06 AM
Subject: Re: That Tek 405x QIC Tape.


> 
> 
> On 10/3/17 2:50 AM, Jos Dreesen via cctalk wrote:
> 
>> Al is maintaining a set of ROM images for these machines, are tape images 
>> covered somewhere ?
>> Do we have an fixed tape image format, as has been done with Dave's IMD for 
>> floppies ?
> 
> As far as I know, no one has successfully made a copy of a Tek cartridge tape 
> in an image format.
> The tapes use two tracks, one for clock and one for data. Encoding beyond 
> that has not been determined.
> I still have several boxes of these including ones that are supposed to have 
> Battlestar Galatica data
> but I have bigger projects to deal with right now.
--
Sounds like a similar system to what Burroughs used on their cassettes; I 
always thought that they'd be a lot easier to read than the 'normal' formats 
with embedded clock signals and always intended to try to read some of the 
tapes I have here some day. 

May have to move it up a few pages of my to-do list now that you've reminded 
me, although I doubt that there's much interest 'out there' in 'L' series 
software...

m


Re: That Tek 405x QIC Tape.

2017-10-03 Thread Jos Dreesen via cctalk

On 03.10.2017 16:59, Al Kossow via cctalk wrote:



On 10/3/17 2:50 AM, Jos Dreesen via cctalk wrote:

That "famous" QIC tape unit



Tektronix 405x tapes aren't QIC

They are 3M DC series cartridges, but the encoding is not a QIC standard.




The problems, alas, are the same.



Re: That Tek 405x QIC Tape.

2017-10-03 Thread Al Kossow via cctalk


On 10/3/17 2:50 AM, Jos Dreesen via cctalk wrote:

> Al is maintaining a set of ROM images for these machines, are tape images 
> covered somewhere  ?
> Do we have an fixed tape image format, as has been done with Dave's IMD for 
> floppies ?

As far as I know, no one has successfully made a copy of a Tek cartridge tape 
in an image format.
The tapes use two tracks, one for clock and one for data. Encoding beyond that 
has not been determined.
I still have several boxes of these including ones that are supposed to have 
Battlestar Galatica data
but I have bigger projects to deal with right now.





Re: That Tek 405x QIC Tape.

2017-10-03 Thread Al Kossow via cctalk


On 10/3/17 2:50 AM, Jos Dreesen via cctalk wrote:
> That "famous" QIC tape unit


Tektronix 405x tapes aren't QIC

They are 3M DC series cartridges, but the encoding is not a QIC standard.





That Tek 405x QIC Tape.

2017-10-03 Thread Jos Dreesen via cctalk

That "famous" QIC tape unit

...has been talked about a lot, still some things are still not clear to me.


Baking : is this a last-resort means of reading some valuable tape, or a means 
to restore them for a further few years of usage ?
I intend to bake mine before usage, although a few unused, still shrinkwrapped, 
tapes seem to be in excellent condition, including tensioning belt.
Those I might try without baking.

The belt : is the elastibands method usable for more than a few reads/writes, 
or is robbing belts from 6150's really the only way ?

Belts seem to come in 2 guises : black belts, often dead and somewhat sticking 
to the magtape itself, and smaller white belts, always broken, and bonded 
firmly to the magnetic coating.
Sadly all my Tek Library and Test tapes are of the latter variant.

Al is maintaining a set of ROM images for these machines, are tape images 
covered somewhere  ?
Do we have an fixed tape image format, as has been done with Dave's IMD for 
floppies ?



Background : currently in the process of restoring both my 4052's.
Have the maintenance manual and spares, so there is hope.

But ideally I would also like to keep using the cartidge drive.
Fool's errant or workable option ?



Jos