DEC Paper Tape Punch/Reader Pricing

[Chuck(G)]

Modern computers don't have much of this.

...including people who sit at them.

 

[hunterjwizzard]

I keep thinking there must be some 1" wide ribbons and I look for this in craft stores.

This must be an interesting question for the store employees. "Hello. I am wondering if this ribbon would work to replace the DEC paper tape in a PDP-8?"

 

[DougIngraham]

This must be an interesting question for the store employees. "Hello. I am wondering if this ribbon would work to replace the DEC paper tape in a PDP-8?"

Ha! I will have to try asking like that sometime just to see the response.

I ask if they have 1" wide ribbons. Of course they don't know if they have any that are 1" wide.

And I have not found anything that is thin enough and the correct width.

 

[1944GPW]

If a roll of the appropriate paper thickness is found, it might be cut into tape widths using a paper slitting machine. Here's a small commercial one which may not accommodate large rolls but the idea could be enough to fab up a crude version with welded frame, bearings, slide rod, blade etc. in a home workshop.
https://www.ebay.com/itm/374941788162

I have been working on the model for a 3D-printed roll paper tape fan-fold machine (8-1/2" lengths) for the last 5 years, every year or so I drag it out and do a little more on it.

 

[Roland Huisman]

Just to give you an idea on pricing, I bought a fully serviced, restored and working PC04 with controller (PDP11) for 1500 EUR + shipping a couple of years ago.

I assume you meant a PC05 for your PDP11?

I have all the fun stuff that I want on my PDP8 and 11 machines. PC04 / PC05, RK05 drives, TU56 drives and RX01/02 drives. The TU56 is by far my favourite but the RX01/02 is the easiest to get on a PDP8/M. I've made clones of the RX8E controllers a while back. But there is a guy on Ebay who has a pile for sale. I would say, get one while you can... A RX02 drive would not be too hard to find. And in the meanwhile you could use a floppy emulator with an Arduino Mega. That works blazing fast The RK05 controller is a three board set and these are not easy to find. RK05 drives can be found, but suitable 16 sector disk packs is another story. The TU56, oh well... everyone should have at least one... Just because of the looks and spinning of the tapes... But finding one can be a challenge.

I'm using the PC04/05 reader/punchers to copy papertapes to files. I have a few boxes of fan folded tape, but since these are getting scarce I'm careful to use them.

About pricing, I've got an incomplete PC05 for free. I'm making is complete again, step by step. So it is just what you are looking for. A tested and fully functional PC04/05 complete with controller, or one with a bit of work... If you are in a hurry you will pay the highest price, if you have time it might be a lot easier.

Regards, Roland

 

[djg]

(Edit: Backing up a RK05 disk to the PTP: would take 30 days assuming you can keep the punch fed with paper tape. Read time for restore however would only be a mere 6 days reading 24*7.)

RK05 is 203 tracks, 2 surfaces, 16 sectors per track, 256 words per sector
203*2*16*256 = 1662976 words or 2494464 bytes

Punch is 50 characters per second
2494464/50 = 49889 seconds

49889/60/60 = 13.86 hours. Still not going to try.

Didn't find how long a box of tape was in a quick search to see how many boxes that would be.

 

[DougIngraham]

RK05 is 203 tracks, 2 surfaces, 16 sectors per track, 256 words per sector
203*2*16*256 = 1662976 words or 2494464 bytes

Punch is 50 characters per second
2494464/50 = 49889 seconds

49889/60/60 = 13.86 hours. Still not going to try.

Didn't find how long a box of tape was in a quick search to see how many boxes that would be.

Well, that makes it almost seem reasonable with compression. Between 3 and 4 hours. Restore would then be somewhere between 26 and 34 minutes.

The tape would be approximately 20787 feet uncompressed or about 4 miles (7.95 km). I don't know how long a box of tape is either.

Now I wish I had checked his math.

 

[czunit]

RK05 is 203 tracks, 2 surfaces, 16 sectors per track, 256 words per sector
203*2*16*256 = 1662976 words or 2494464 bytes

Punch is 50 characters per second
2494464/50 = 49889 seconds

49889/60/60 = 13.86 hours. Still not going to try.

Didn't find how long a box of tape was in a quick search to see how many boxes that would be.

Wow, I really screwed up my math somehow. My error. Ah I'll bet I calced it at 50 chars per minute, not second. Or maybe I was thinking an RM80....

 

[thunter0512]

...

I've made clones of the RX8E controllers a while back. ...
The RK05 controller is a three board set and these are not easy to find. RK05 drives can be found, but suitable 16 sector disk packs is another story.

...

Regards, Roland

Hi Roland, there is shortage of RK8E controllers. With George Wiley's nice RK05 emulator there is an increased demand for these controllers. You have cloned a number of other Omnibus controllers. Would you be able and willing to do a RK8E clone? Vince Slyngstad has recreated the original PCBs but some of the parts have become unavailable, so a build is difficult if not impossible. Unfortunately I don't have the KiCAD or Eagle skills to do this myself.

 

[Roland Huisman]

Hi Roland, there is shortage of RK8E controllers. With George Wiley's nice RK05 emulator there is an increased demand for these controllers. You have cloned a number of other Omnibus controllers. Would you be able and willing to do a RK8E clone? Vince Slyngstad has recreated the original PCBs but some of the parts have become unavailable, so a build is difficult if not impossible. Unfortunately I don't have the KiCAD or Eagle skills to do this myself.

Good idea, I have a spare functional Rk05 doing nothing. I'm currently moving to another home and I'm going to study next year. So a bit busy but I like the idea. I'm wondering, did Vince start with a cpld/fpga version of the RK8E? That could be a single board instead of three boards. The TTL TD8E version is also on my todo/wish list.

Regards, Roland

 

[vrs42]

Good idea, I have a spare functional Rk05 doing nothing. I'm currently moving to another home and I'm going to study next year. So a bit busy but I like the idea. I'm wondering, did Vince start with a cpld/fpga version of the RK8E? That could be a single board instead of three boards. The TTL TD8E version is also on my todo/wish list.

Regards, Roland

I did start a design like that, but ran into a problem that the boards have a lot of top connector and other pins, so the pin counts exceeded those available for the CPLD by a good margin. This is also worsened by the thing being a DMA device, which is inherently more complicated and pin intensive than polled I/O.

That argued that a "one board, one CPLD" approach wasn't going to fit, and opened a can of worms about how to partition the design into CPLD-sized chunks. I had some ideas about that, but basically didn't get that far.

The CPLD TD8E, on the other hand, does seem doable. I even had boards made at one point, though I didn't like the mechanical design (daughter card for the original memory card), and never really persued debugging the thing.

 

[Schroeder]

I'm happy that I got a PDP/8 for 500 bucks noone wanted some years back. The old man did work for Siemens and did build custom PDPs. The reason why this 8 has a light brown plate behind the front. I love the papertape puncher and with some luck the system will be back alive in September. I like this thread!

 

[hunterjwizzard]

Any chance we can get a distance shot of the whole machine? I've never had a good visual of what a full PDP looks like.

 

[Roland Huisman]

Any chance we can get a distance shot of the whole machine? I've never had a good visual of what a full PDP looks like.

I'm also curious to the complete setup from Schroeders PDP8/e.

But it really depends on the options you have for your machine. Here you can see some of my machines. My goal is to limit to one H960 rack for one CPU and its peripherals. But you can build a complete wall with 6 foot tall 19 inch racks full of stuff...

Regards, Roland

 

[Nevets01]

Any chance we can get a distance shot of the whole machine? I've never had a good visual of what a full PDP looks like.

I'm also curious to the complete setup from Schroeders PDP8/e.

But it really depends on the options you have for your machine. [...]

Seconding both the curiosity, and the fact that PDPs can look very different depending on what options, which model, and the disposition of the owner. For contrast, here's my 8/I:


I have thought about taking the TC01 and the TU55 out, and putting them in the same rack as the 8/I, but there's two problems with that, one being the interesting other stuff in the rack (those extra panels were added by those who used the machine) and two being the fact that while one TU55 will fit in the same rack as the CPU, two will not, and I am still holding out hope for a second.
(if anyone knows where I could get a second TU55 to fill that empty slot, let me know, heh)

 

[thunter0512]

Good idea, I have a spare functional Rk05 doing nothing. I'm currently moving to another home and I'm going to study next year. So a bit busy but I like the idea. I'm wondering, did Vince start with a cpld/fpga version of the RK8E? That could be a single board instead of three boards. The TTL TD8E version is also on my todo/wish list.

Regards, Roland

Would it help to setup a crowd funding scheme like Kickstarter to fund the development of an RK8E controller clone?

 

[pbirkel@gmail.com]

Would it help to setup a crowd funding scheme like Kickstarter to fund the development of an RK8E controller clone?

It seems to me that the critical constraint is the lack of a developer ... not the cost of materials. Unless you're proposing to hire a developer?

 

[Roland Huisman]

Would it help to setup a crowd funding scheme like Kickstarter to fund the development of an RK8E controller clone?

No, for me the fun is enough

 

[vrs42]

I'm wondering, did Vince start with a cpld/fpga version of the RK8E? That could be a single board instead of three boards. The TTL TD8E version is also on my todo/wish list.

Since a CPLD version of the RK8E looks like a pile of work, I'm thinking a shorter path might be simple TTL replacements for the old DEC chips. As mentioned earlier, the DEC board layouts are generally available in CAD tools, and there is probably demand for 8266 replacements and such. Perhaps JLC or similar would be able to build the replacements affordably.

In theory, a sufficient library of replacements should allow the original layouts to be populated.

 

[hunterjwizzard]

I have thought about taking the TC01 and the TU55 out, and putting them in the same rack as the 8/I, but there's two problems with that, one being the interesting other stuff in the rack (those extra panels were added by those who used the machine) and two being the fact that while one TU55 will fit in the same rack as the CPU, two will not, and I am still holding out hope for a second.
(if anyone knows where I could get a second TU55 to fill that empty slot, let me know, heh)

Very cool picture.

Is that a standard 19" rack? If so, then it is possible to get racks larger than 48U( think 52 off the shelf?). Of course then weight becomes a serious issue, and honestly that thing looks cooler in 2 racks anyway.

At home I put a 32U rack on top of a custom-made cabinet because I don't like to bend over.