Controller for RL02/RL01 disk drive in a PDP8 straight 8

[rorypoole]

what about using the RL01/RL02 with a Harris HD1-6120-9, and connecting the 6120 to the straight 8, so the 6120 would work like an I/O processor, the harris HD1-6120-9 is a pdp-8/E on a chip and good for upto 5.1mhz!

I found a data sheet for the PDP-8/E on a chip!
https://www.grc.com/sn/files/HD6120_Specifications.pdf

 

[Lou - N2MIY]

There was only one device that ever did that. It's the elusive RL278. I would love to have one and have never seen one. From research I have done on this animal, even Charles Lasner has never seen one.

The Decmate 1 (VT278 ) used the 6120 and the RL278 was the RL01/02 interface for the Decmate 1. OS78 provides the support for the RL278.

I would be amused to know if anyone here has ever seen one or has one....

Lou

 

[rorypoole]

I found a RL278 but it has a list price of $7600 and no pic!!!
the RL278 was for the Decmate so probably not useful to me
and it would be very useful to be able to take one of the 3 standard types of DEC cards

There was only one device that ever did that. It's the elusive RL278. I would love to have one and have never seen one. From research I have done on this animal, even Charles Lasner has never seen one.

The Decmate 1 (VT278 ) used the 6120 and the RL278 was the RL01/02 interface for the Decmate 1. OS78 provides the support for the RL278.

I would be amused to know if anyone here has ever seen one or has one....

Lou

 

[rorypoole]

I dont like the fact that it looks like regular power cycling the DS32 is not good for it but I found David Gesswein's DS32 Emulator Board, its not the same as a real drive, but it is the equivalent of a USB flash drive for the pdp computers!
http://www.pdp8online.com/dfds32/emulator/index.shtml

 

[rorypoole]

I have picked up my the first RL02 and diskpack!

 

[DaveH]

Well done, iv not had much success finding them in the UK but am waiting ( and hoping ) to get 2 from Germany shortly.
Dave

 

[rorypoole]

there is a post on the site about where to get new filters, I will be interested to see how you get your 2 RL02's up and running, do you have or are you getting some diskpacks?
good luck with your RL02's

 

[DaveH]

Yes I saw that post, I must get round to following it up, postage may be a bit much mind you, I recently bought some RL02 spares from the states, including a head assembly and a spindle and the postage wasent to bad BUT it varies a lot, often its more than the item!!.
I do in fact already have 2 and a half RL02, the half being one that was underwater in a flood so its all seized solid and I dont hold out much hope for it, it was when looking for spares that i found the drives in Germany, just hope they arrive ok, I got the seller to lock the heads but still its a heavy beast. The other 2 RL are also in a pretty poor state , will need a lot of TLC Iv not yet had the time to actually work with the RL's , Iv just got my Lab 8 fully up and running
http://www.flickr.com/photos/78027915@N04/8730126430/
and the current project is to revive the second of my 8M's, initially with an RK05 THEN try it with an RL if I can get the RL8A to run, its rather corroded as was covered with mouse droppings !!,I will let you know how it goes.
Cheers
Dave

 

[rorypoole]

I think you should use weak bleach were the mouse was! or at lest rinse with bicarbonate of soda to neutralize the acid from the mouse!
I did not know I should have locked the heads!! how do you lock the heads? I will have to know for when moving the other RL02 drives.
the Lab 8 looks great! one thing I would like to do with a poor RL02, is make it into a diskpack platter tester, to test its aliment, how long was your RL02 underwater?

Yes I saw that post, I must get round to following it up, postage may be a bit much mind you, I recently bought some RL02 spares from the states, including a head assembly and a spindle and the postage wasent to bad BUT it varies a lot, often its more than the item!!.
I do in fact already have 2 and a half RL02, the half being one that was underwater in a flood so its all seized solid and I dont hold out much hope for it, it was when looking for spares that i found the drives in Germany, just hope they arrive ok, I got the seller to lock the heads but still its a heavy beast. The other 2 RL are also in a pretty poor state , will need a lot of TLC Iv not yet had the time to actually work with the RL's , Iv just got my Lab 8 fully up and running
http://www.flickr.com/photos/78027915@N04/8730126430/
and the current project is to revive the second of my 8M's, initially with an RK05 THEN try it with an RL if I can get the RL8A to run, its rather corroded as was covered with mouse droppings !!,I will let you know how it goes.
Cheers
Dave

 

[rorypoole]

I cant open it, maybe there is a diskpack still in it!!!!

I have not powered it up yet and dont plan to till I have checked it out
I have done some reading and it looks like I will have to look out for crumbling dec fome and I now know how to park the heads, I hope its not to late!

 

[DaveH]

I cant open it, maybe there is a diskpack still in it!!!!

I have not powered it up yet and dont plan to till I have checked it out
I have done some reading and it looks like I will have to look out for crumbling dec fome and I now know how to park the heads, I hope its not to late!

Hi, DONT try and forc it open, with the power off the latch for the top is probably engaed, there is an easyish way round this, dont have time right now but will mail u the gen I sent to my guy in germaney to open and log the heads.
Dave

 

[DaveH]

Hi, DONT try and forc it open, with the power off the latch for the top is probably engaed, there is an easyish way round this, dont have time right now but will mail u the gen I sent to my guy in germaney to open and log the heads.
Dave

Ok , to open the drive cover manually, position the drive with the front bezzel just over the front of the bench, ie drive not resting on the lower lip of the bezzel. Remove the 6 screws holding the bezzel on, 3 a side, watch out when the bezzel comes of as there is a cable connection it to the drive.
At the top center of the drive front now exposed there is a small, 1mm or so hole, push a short , stiff , wire, ie paper clip, or i use the wee tool I use to open CDROM drives , into this hole, push firmly but not hard, you may need to angle the wire down a bit and wiggle, this thould trip the latch and when you remove the wire the top will open.
If there is a cartridge in DONT just remove it in case the heads have moved out as if you do you will damage them, and i expect in this case you would have to power up the drive to make sure the heads are retracted. Iv not had this happen but I suspect it could.
Re your PM, the absolute filter for the RK05 and the RL02 are completely different and not interchangeable. I have some RK05's but no RL02's .
The drive that got flooded was only under water for about 5 hours but I did not realize it at the time as the rest of my workshop and my house was also underwater !!, and by the time i did find out that it had got wet the damage was done, I now have spares for the main boards, the haed assembly and the spindle and if I can uncease the motor its possible I could get it working but my main hope is that he 2 from Germany will arrive intact and in better condition, we will see
Dave

 

[rorypoole]

getting the RL02 drive back home

getting the RL02 drive back home

it was a 30 walk and 4 trains back, but I now have a RL02 drive with a disk pack, 4 used pdp12 packplane parts, that will do 50% of the basic straight 8!