Re: Keyboard storage (Alan Perry)
> On Dec 22, 2020, at 6:41 PM, Raymond Robinson via cctech > wrote: > > Hi Alan, > > I go to my local shopping center. > The fish shop there, has the fish delivered in white foam boxes. > Some are long with lids. > I go dumpster diving and collect them. > They are suitable for keyboards, > depends on the length of the keyboard, > and the length of the fish. > > Regards > Ray Nice, but watch out for static electricity. paul
Keyboard storage (Alan Perry)
Hi Alan, I go to my local shopping center. The fish shop there, has the fish delivered in white foam boxes. Some are long with lids. I go dumpster diving and collect them. They are suitable for keyboards, depends on the length of the keyboard, and the length of the fish. Regards Ray > On Mon, 2020-12-21 at 22:17 -0800, Alan Perry via cctalk wrote: >> I have a bunch of Sun keyboards that I need to store more >> efficiently >> and don't want to risk damaging by stacking on top of each other. >> They >> are Type 4s, 5s, and 6s (without the wrist rest), maybe 10 in total. >> Anyone here know of a box or boxes that would work well for this? >> >> alan
Re: RL02 Tracking (Aaron Jackson)
> > Aaron, > > One thing I would check is the motor bearings. What happens on electro > mechanical assemblies left in store for years is that ball bearing > grease lube dries out and hardens, resulting in lumpy rotation and > increased friction that can be detected by rotating the spindle by > hand. RLxx series drives were very reliable typically, but the head > movement assy is pretty cheap and cheerful. Converting spindle to > linear movement, minimum parts count, dc brush brush motor, means that > all the bits need to be smooth in operation, with no stiction anywhere > in it's travel. > > I would take the motor out and if it can't be stripped to clean the > bearings, use a dab of light clock oil to relube. Also, check the > brushes and clean / polish the commutator. Any other ball bearings > in the path, same process. DC brush motors can be a nightmare for > that sort of precision positioning application... > > Chris Thanks Chris, I will look into trying to measure the wobble (if there is any present) of the spindle. Might be a fun project to strip this down anyway and see what's going on. Hopefully not too much more complicated than a bicycle but we'll see... Aaron This message and any attachment are intended solely for the addressee and may contain confidential information. If you have received this message in error, please contact the sender and delete the email and attachment. Any views or opinions expressed by the author of this email do not necessarily reflect the views of the University of Nottingham. Email communications with the University of Nottingham may be monitored where permitted by law.
RL02 Tracking (Aaron Jackson)
On 12/22/20 18:00, cctech-requ...@classiccmp.org wrote: Send cctech mailing list submissions to cct...@classiccmp.org To subscribe or unsubscribe via the World Wide Web, visit http://www.classiccmp.org/mailman/listinfo/cctech or, via email, send a message with subject or body 'help' to cctech-requ...@classiccmp.org You can reach the person managing the list at cctech-ow...@classiccmp.org When replying, please edit your Subject line so it is more specific than "Re: Contents of cctech digest..." Today's Topics: 1. RL02 Tracking (Aaron Jackson) 2. Re: RL02 Tracking (Aaron Jackson) 3. Re: RL02 Tracking (Jon Elson) 4. Re: RL02 Tracking (Josh Dersch) 5. Re: RL02 Tracking (Aaron Jackson) 6. Re: tty and video displays (Jules Richardson) 7. Re: Keyboard storage (Guy Sotomayor) 8. Wordperfect 6.0 for DOS (Van Snyder) 9. Re: RL02 Tracking (Noel Chiappa) 10. Keyboard storage (Alan Perry) 11. Re: Keyboard storage (Warner Losh) 12. RE: Keyboard storage (Ali) 13. Re: Keyboard storage (Alan Perry) 14. RE: Keyboard storage (Ali) 15. Re: Keyboard storage (Alan Perry) 16. Re: Keyboard storage (Guy Sotomayor) 17. RE: Keyboard storage (ED SHARPE) 18. Re: RL02 Tracking (Christian Corti) 19. Re: Keyboard storage (Patrik Schindler) 20. Re: RL02 Tracking (Aaron Jackson) 21. Re: RL02 Tracking (Aaron Jackson) 22. Re: Keyboard storage (Alan Perry) 23. Re: Keyboard storage (Bill Degnan) 24. Re: Ouch, but 2 Perqs out. (Why 42? The lists account.) 25. Re: Ouch, but 2 Perqs out. (Why 42? The lists account.) 26. Re: Ouch, but 2 Perqs out. (Tony Duell) 27. Re: Ouch, but 2 Perqs out. (Tony Duell) 28. Re: Ouch, but 2 Perqs out. (Chris Zach) 29. RE: Keyboard storage (Fred Cisin) 30. RE: Keyboard storage (ED SHARPE) -- Message: 1 Date: Mon, 21 Dec 2020 19:08:14 + From: Aaron Jackson To: "cctalk@classiccmp.org" Subject: RL02 Tracking Message-ID:<91bim8vyo2q@mimas.cs.nott.ac.uk> Content-Type: text/plain; charset="iso-8859-1" Hi everyone I've posted a few times over the years about RL02 drives and my difficulty getting them working (no luck so far!). I've spent the past few days working on one of them and have made some progress. The status currently is that the heads will load, and the ready lamp flashes as the heads wobble back and forth very slightly, trying to lock onto the outer servo guard band. Probing TP2 of the read/write module, I can see the S1 servo burst flash (roughly in time with the ready lamp). If I disconnect power to the servo motor, I can manually move the head onto the outer guard band (less than a mm away) and monitoring the position signal (TP15 on the drive logic module) shows this to be close to 0. So, I'm very confused. I've worked through chapter 3 multiple times... - voltage checks - all good - sector transducer output check - all good - sector pulse timing check - all good - read signal amplitude check and adjustment - all good - positioner radial alignment - required some tweeking but is good now - head alignment - looks good to me - spindle runout check - a little noisy but within spec - position signal gain check - looked ok - tachometer ac noise pickup check - this one didnt look so good Supposedly if the main drive motor is bad it will emit noise and cause the tachometer (just a coil of wire on the head carriage) to produce spikes. Mine does look quite noisy but I'm not sure what's causing it. I would expect that if it was picking up noise, I'd be able to detect this with my oscilloscope probe by putting it close to the motor, but I can't. Any ideas? Also, thanks to pjustice on irc who suggested checking the spindle grounding button. Mine is very worn out but I've been able to apply some pressure to it from the under side which reduces the resistance of the spindle to ground, from 400 ohm to 0 ohm. This didn't make the situation any better though. Still, the situation over all is much better now than it was last time I looked at the drive (over two years ago now I think). Previously the heads would attempt to load and then the fault lamp would come on immediately. At least now it's trying to lock onto a track. I have the same results with two cartridges (which is all I have!). If anyone has any ideas I'd love to hear them! Aaron Aaron, One thing I would check is the motor bearings. What happens on electro mechanical assemblies left in store for years is that ball bearing grease lube dries out and hardens, resulting in lumpy rotation and increased friction that can be detected by rotating the spindle by hand. RLxx series drives were very reliable typically, but the head movement assy is pretty cheap and cheerful. Converting spindle to linear movement, minimum parts count, dc brush brush motor, means that all the bits need to be smooth in operation, with no stiction anywhere in it's
Compiling Fortran77 on the Pro: Where the heck are the library modules?
So I'm working on compiling some programs on my Pro/380. 2.0 OS, Fortran77 compiler, Empire is the sample game. I got it to compile properly but when I try to link it the linker/tkb/pab fails with a bunch of undeclared references. Some of them are in the F77FCS.OLB library files on my pdp11/83 (M+ 4.6) like $CLOS, ISF$, $OSF, and $OPEN, but others like $EOLST, IOAB$, IOAI$, TT$EFN, and others are missing as well. Did DEC really jerk people around so badly by selling the FCS or RMS libraries as a separate installed product? I see some reference to RMSLIB.OLB but it's not on this system. Weird. CZ
DEC H765 line interference caps
Hi all, I’m just starting in on a PDP-11/34 for a friend (happy holidays!) I currently have the H765 power supply torn down for cleaning, inspection, and testing as a first step. While I have the transformer out on the bench, I’m wondering about the line interference supression caps on the “CAP MOV” board attached to the transformer. These are CDE 220 VAC .1 MFD, across the line, in parallel with some metal oxide varistors. Drawing on collective experience here: would I be well advised to go ahead and swap these out for some modern X2 safety caps while I have the supply apart? Or are these in the “oh those are rock solid; I wouldn’t touch em unless they were faulted” category? cheers! —FritzM.
Re: RL02 Tracking
On 22 December 2020 at 22:17 GMT, shad via cctalk wrote: >> The ready lamp flashes not when the servo burst is >visible, but when the > heads are just before it. >> Why? Well, I probably set the gain too high on the read/write module. > > Hello, > I'm sure you read the manual, however I add some explanation to be sure. > The best head position is not where a servo track is at maximum amplitude > (head is exactly centered to a servo track), but where you read two servo > tracks with the same amplitude (so head is exactly between two servo > tracks, in middle position). > Comparative measurement of two servo tracks allow the servo control to > understand the position of the head in respect to data track. > If the best position for data track is not where servo have same amplitude > probably the head is misaligned or the spring support of the head bent / > deformed. > To analyze head circuits you need a good oscilloscope, you should be able > to see burst of servo tracks and data tracks too, with two channels you can > understand if analog to digital threshold / pulses signal conversions do > work as expected. > Time ago I fixed an RL02 having a malfunctioning head amplifier circuit. > The gain was too low. When I increased it rotating variable resistor, the > circuit begun to ring (barely auto-oscillate), so was nearly unstable. Data > and servo signals were corrupted, but this was visible only zooming on > oscilloscope after careful trigger alignment. > I don't remember exactly what I did, but some capacitors needed > replacement, then I tuned head gain while loading a platter to the best > position for operation, maybe slightly lower than manual recommendations. > Then it worked perfectly. > > Andrea Hi Andrea, Thanks for this. My understanding is that the S1 and S2 servo bursts are passed through a comparator and then integrated. When the head is directly over the target track, S1 (becomes E1 after integration) is a perfect saw tooth, while E2 'saw tooths' away from 0V. After performing the amplitude adjustment, the potentiometer was very close to max, and I was getting around 650mV from the cartridge, but the noise floor was quite high. The manual also says that the outer guard track should not have an amplitude greater than 2.5V. Presumably the amplitude on the platter is higher the further out the track is, perhaps due to the amount of space available given 40 sectors per track. With this amplitude set as mentioned, loading the cartridge results in this head unpredictable oscillating behaviour, but as I mentioned, the ready light only comes on briefly, and only when the heads are before the outer guard. Basically, as far as they could be off the platter before being lifted by the ramp. Reducing the amplitude slightly prevents this oscillating behaviour, but the ready lamp does not come on at all. Increasing it to the very max causes very extreme oscillation, sometimes aggressively unloading the heads. I happen to have three of the read/write modules, and they all exhibit this behaviour. Not to say that caps don't need to be changed, but it seems unlikely that all of them would need this. I have a fairly decent scope and have been able to do some very nice captures of the servo bursts. They are not perfectly sinusoidal but I think close enough given the age of the heads. I'll go through the caps at some point anyway to double check. Looking at the schematic I'm guessing they are either ceramic or tants. thanks again, Aaron This message and any attachment are intended solely for the addressee and may contain confidential information. If you have received this message in error, please contact the sender and delete the email and attachment. Any views or opinions expressed by the author of this email do not necessarily reflect the views of the University of Nottingham. Email communications with the University of Nottingham may be monitored where permitted by law.
Re: RL02 Tracking
> The ready lamp flashes not when the servo burst is >visible, but when the heads are just before it. > Why? Well, I probably set the gain too high on the read/write module. Hello, I'm sure you read the manual, however I add some explanation to be sure. The best head position is not where a servo track is at maximum amplitude (head is exactly centered to a servo track), but where you read two servo tracks with the same amplitude (so head is exactly between two servo tracks, in middle position). Comparative measurement of two servo tracks allow the servo control to understand the position of the head in respect to data track. If the best position for data track is not where servo have same amplitude probably the head is misaligned or the spring support of the head bent / deformed. To analyze head circuits you need a good oscilloscope, you should be able to see burst of servo tracks and data tracks too, with two channels you can understand if analog to digital threshold / pulses signal conversions do work as expected. Time ago I fixed an RL02 having a malfunctioning head amplifier circuit. The gain was too low. When I increased it rotating variable resistor, the circuit begun to ring (barely auto-oscillate), so was nearly unstable. Data and servo signals were corrupted, but this was visible only zooming on oscilloscope after careful trigger alignment. I don't remember exactly what I did, but some capacitors needed replacement, then I tuned head gain while loading a platter to the best position for operation, maybe slightly lower than manual recommendations. Then it worked perfectly. Andrea
Wordperfect 6.0 for DOS
Relisted Wordperfect 6.0 for DOS on EBay. Item number 224289791291. Van Snyder van.sny...@sbcglobal.net
RE: Keyboard storage
Hopefully someone will have some The blasted one is on the left side of the keyboard. Having a spare for the right side probably not a bad idea too... We were missing keyboards and got this like new one gifted to us. It was heartbreaking to see it damaged in shipping. We have a couple early 5150 umits with expansion chassis. Although only one of the monster interconnect cables between the pc and expansion chassis. Looking for posters lapel pins and other display art to fill in open areas... Any other ideas wekcome! Ed# On Tuesday, December 22, 2020 Fred Cisin via cctalk wrote: Ed, that was excellent! We appreciate the extra effort. Alas, you are 15 years too late for my extra 5150 keyboard parts. They didn't make it through the third move (Ben Franklin commented how that was as disruptive as a fire) -- Grumpy Ol' Fred ci...@xenosoft.com On Tue, 22 Dec 2020, ED SHARPE via cctalk wrote: > > Let's try this... > > Had a ibm orig pc key board shipped in large flat rate Game size box. > > Alas it was dropped on the corner and torn somewhat. > > I had to remount keyboard pc inside the case that had moved and hardest part > was getting ground wire back > > Worse part was one of the corner edge flip up things that keeps key at an > angle bad snapped off. Museum needs parts to fix this as it is nice to > display keyboard at an angle > > Alas that particular Clicky keyboard is extremely heavy ... this is the one > for first ever ibm pc. Corner drop shock is a killer. > > Beware pack these early keyboards really well... > > OK does anyone have parts for the little mechanism on the end that keeps > keyboard tilted at an angle? > > > .Ed Sharpe archivist for SMECC museum project > On Tuesday, December 22, 2020 Fred Cisin via cctalk cctalk@classiccmp.org> wrote: > On Tue, 22 Dec 2020, ED SHARPE via cctalk wrote: >> Had a ibm orig pc key board shipped in large flat rate. Game size box. Alas >> was,dropped on. Ornery and torn some on box... I had to remount keyboard pc >> inside that had moved lo and neef nd one of the corner edge til tje kry bad >> snapped off... that particular Clicky keyb I ad is extremely heavy for >> first ever ibm pc. Be ware pack really well.. >> Help anyone got parts for the tilter >> ...thing for these keyboards >> ...ed sharpe > > May we suggest that you switch temporarily to a working keyboard (or > "keyb" if you prefer) until you can repair the shipping damage. > What is "lo and neef nd"? > "til tje kry bad"? > It must be hard on you to have to proofread and fix all of the errors that > it creates.
Re: Keyboard storage
On 12/22/20 9:49 AM, ED SHARPE via cctalk wrote: > > Let's try this... > > Had a ibm orig pc key board shipped in large flat rate Game size box. > > Alas it was dropped on the corner and torn somewhat. > > I had to remount keyboard pc inside the case that had moved and hardest part > was getting ground wire back > > Worse part was one of the corner edge flip up things that keeps key at an > angle bad snapped off. Museum needs parts to fix this as it is nice to > display keyboard at an angle > > Alas that particular Clicky keyboard is extremely heavy ... this is the one > for first ever ibm pc. Corner drop shock is a killer. > > Beware pack these early keyboards really well... > > OK does anyone have parts for the little mechanism on the end that keeps > keyboard tilted at an angle? Try the folks at https://www.clickykeyboards.com/--they tend to hoard a lot of old parts and are quite reasonable about selling them. --Chuck
RE: Keyboard storage
Ed, that was excellent! We appreciate the extra effort. Alas, you are 15 years too late for my extra 5150 keyboard parts. They didn't make it through the third move (Ben Franklin commented how that was as disruptive as a fire) -- Grumpy Ol' Fred ci...@xenosoft.com On Tue, 22 Dec 2020, ED SHARPE via cctalk wrote: Let's try this... Had a ibm orig pc key board shipped in large flat rate Game size box. Alas it was dropped on the corner and torn somewhat. I had to remount keyboard pc inside the case that had moved and hardest part was getting ground wire back Worse part was one of the corner edge flip up things that keeps key at an angle bad snapped off. Museum needs parts to fix this as it is nice to display keyboard at an angle Alas that particular Clicky keyboard is extremely heavy ... this is the one for first ever ibm pc. Corner drop shock is a killer. Beware pack these early keyboards really well... OK does anyone have parts for the little mechanism on the end that keeps keyboard tilted at an angle? .Ed Sharpe archivist for SMECC museum project On Tuesday, December 22, 2020 Fred Cisin via cctalk wrote: On Tue, 22 Dec 2020, ED SHARPE via cctalk wrote: Had a ibm orig pc key board shipped in large flat rate. Game size box. Alas was,dropped on. Ornery and torn some on box... I had to remount keyboard pc inside that had moved lo and neef nd one of the corner edge til tje kry bad snapped off... that particular Clicky keyb I ad is extremely heavy for first ever ibm pc. Be ware pack really well.. Help anyone got parts for the tilter ...thing for these keyboards ...ed sharpe May we suggest that you switch temporarily to a working keyboard (or "keyb" if you prefer) until you can repair the shipping damage. What is "lo and neef nd"? "til tje kry bad"? It must be hard on you to have to proofread and fix all of the errors that it creates.
RE: Keyboard storage
Let's try this... Had a ibm orig pc key board shipped in large flat rate Game size box. Alas it was dropped on the corner and torn somewhat. I had to remount keyboard pc inside the case that had moved and hardest part was getting ground wire back Worse part was one of the corner edge flip up things that keeps key at an angle bad snapped off. Museum needs parts to fix this as it is nice to display keyboard at an angle Alas that particular Clicky keyboard is extremely heavy ... this is the one for first ever ibm pc. Corner drop shock is a killer. Beware pack these early keyboards really well... OK does anyone have parts for the little mechanism on the end that keeps keyboard tilted at an angle? .Ed Sharpe archivist for SMECC museum project On Tuesday, December 22, 2020 Fred Cisin via cctalk wrote: On Tue, 22 Dec 2020, ED SHARPE via cctalk wrote: > Had a ibm orig pc key board shipped in large flat rate. Game size box. Alas > was,dropped on. Ornery and torn some on box... I had to remount keyboard pc > inside that had moved lo and neef nd one of the corner edge til tje kry bad > snapped off... that particular Clicky keyb I ad is extremely heavy for > first ever ibm pc. Be ware pack really well.. > Help anyone got parts for the tilter > ...thing for these keyboards > ...ed sharpe May we suggest that you switch temporarily to a working keyboard (or "keyb" if you prefer) until you can repair the shipping damage. What is "lo and neef nd"? "til tje kry bad"? It must be hard on you to have to proofread and fix all of the errors that it creates.
RE: Keyboard storage
On Tue, 22 Dec 2020, ED SHARPE via cctalk wrote: Had a ibm orig pc key board shipped in large flat rate. Game size box.?? Alas was,dropped on. Ornery and torn some on box... I had to remount keyboard pc inside that had moved lo and neef nd one of the corner edge til tje kry bad snapped off...?? that particular Clicky keyb I ad is extremely heavy for first ever ibm pc.?? Be ware?? pack really well.. Help anyone got parts for the tilter ...thing?? for these keyboards ...ed sharpe May we suggest that you switch temporarily to a working keyboard (or "keyb" if you prefer) until you can repair the shipping damage. What is "lo and neef nd"? "til tje kry bad"? It must be hard on you to have to proofread and fix all of the errors that it creates.
Re: Ouch, but 2 Perqs out.
I can see that it was a long day - but you are doing good work! Keep it up! Whereabouts is all this heavy lifting taking place, in the US? I wouldn't have expected to see ICL Perqs so far from home ... They're here in the US: I think one of these came from Sparrows Point Beth Steel, I remember seeing one like it in my long since ex girlfriends' house in the 1980's. That brings back bad memories, but I think the juju has faded by now. The brown one is the original Perq 1, as you now know. Since you have take out the hard disk (14 inch Shugart, as I recall) be aware that it should be stored upright. The platters had a tendency to warp under their own weight when stored sideways. Got it. I didn't take the disk out, one is in a frame of a Perq 1 and the other was in a complete-ish P1 that I took the CPU card cage and power supply out to make it light enough to get up the steps. There are some pretty big rubber isolators holding the disk assembly to the frame and yes at the moment it's all stored vertical with the disks pointing up. If it would be useful, when the time comes, I have a couple of ring binders here containing some ICL documentation from 1984-86. E.g. my Perq Specialist Training Notes and a set of Customer Service Information Sheets - for example see listing here: http://paste.c-net.org/RocketsSymbols These have some part numbers and tips which might perhaps be useful. I don't have a Perq, but I would love to get copies of any software that could be retrieved from these systems (Still looking forward to playing Pool (i.e. the game, with the balls) by Nigel Bond (?). Ok. They're safe now and I'll see what else I can retrieve before the end of year. My best chance might be to get the two Canon printers out of there; they are blocking access to other stuff and that would give me room to move more of the Sun junk out of the way to unearth these. Maybe I'll also get the Kaypros out of there as well to unearth that Compucom thing. C
Re: Ouch, but 2 Perqs out.
On Tue, Dec 22, 2020 at 3:53 PM Why 42? The lists account. via cctalk wrote: > > > On Sat, Dec 12, 2020 at 05:56:40PM -0500, Chris Zach via cctech wrote: > > This was a long day. Went over to the house and started working on getting > > the Perqs out of the basement. I've been moving smaller stuff to make room > > and it was time. > > I can see that it was a long day - but you are doing good work! Keep it > up! > > Whereabouts is all this heavy lifting taking place, in the US? I wouldn't > have expected to see ICL Perqs so far from home ... Err, the PERQ was originally designed/built by 3 Rivers Computer Corp in the States. I think some parts of the 2T1 (the one with the 8" Micropolis hard drive), in particular the hard disk interface board and the portrait monitor (based on a Kent Modular Electronics chassis) were from ICL, but the CPU, memory. EIO etc all come from the States. Of course the AGW3300 is an ICLmachine but I feel that's a PERQ in name only -tony
Re: Ouch, but 2 Perqs out.
On Sat, Dec 12, 2020 at 05:56:40PM -0500, Chris Zach via cctech wrote: > This was a long day. Went over to the house and started working on getting > the Perqs out of the basement. I've been moving smaller stuff to make room > and it was time. I can see that it was a long day - but you are doing good work! Keep it up! Whereabouts is all this heavy lifting taking place, in the US? I wouldn't have expected to see ICL Perqs so far from home ... The brown one is the original Perq 1, as you now know. Since you have take out the hard disk (14 inch Shugart, as I recall) be aware that it should be stored upright. The platters had a tendency to warp under their own weight when stored sideways. If it would be useful, when the time comes, I have a couple of ring binders here containing some ICL documentation from 1984-86. E.g. my Perq Specialist Training Notes and a set of Customer Service Information Sheets - for example see listing here: http://paste.c-net.org/RocketsSymbols These have some part numbers and tips which might perhaps be useful. I don't have a Perq, but I would love to get copies of any software that could be retrieved from these systems (Still looking forward to playing Pool (i.e. the game, with the balls) by Nigel Bond (?). Cheers, Robb.
Re: Keyboard storage
ULINE sells a box (you can buy a qty of 1-5-20-etc that fits the dimensions of most any keyboard and would be a good long-term storage solution. I have bought these and they stack well. Bill On Tue, Dec 22, 2020 at 9:11 AM Alan Perry via cctalk wrote: > > > On Dec 22, 2020, at 00:51, Patrik Schindler via cctalk < > cctalk@classiccmp.org> wrote: > > > > Hello Alan, > > > >> Am 22.12.2020 um 07:17 schrieb Alan Perry via cctalk < > cctalk@classiccmp.org>: > >> > >> I have a bunch of Sun keyboards that I need to store more efficiently > and don't want to risk damaging by stacking on top of each other. They are > Type 4s, 5s, and 6s (without the wrist rest), maybe 10 in total. Anyone > here know of a box or boxes that would work well for this? > > > > I’m storing keyboards openly in a shelf, vertical, standing on the small > edge. I alternate them front-back so the slope of the keys array is > compensating itself. Aside from some dust, the packing density is really > good. > > Thanks for the suggestion. > > Unfortunately, since I live on a gravel road, dust is a huge problem here, > so I need an enclosed solution. > > alan > >
Re: Keyboard storage
> On Dec 22, 2020, at 00:51, Patrik Schindler via cctalk > wrote: > > Hello Alan, > >> Am 22.12.2020 um 07:17 schrieb Alan Perry via cctalk : >> >> I have a bunch of Sun keyboards that I need to store more efficiently and >> don't want to risk damaging by stacking on top of each other. They are Type >> 4s, 5s, and 6s (without the wrist rest), maybe 10 in total. Anyone here know >> of a box or boxes that would work well for this? > > I’m storing keyboards openly in a shelf, vertical, standing on the small > edge. I alternate them front-back so the slope of the keys array is > compensating itself. Aside from some dust, the packing density is really good. Thanks for the suggestion. Unfortunately, since I live on a gravel road, dust is a huge problem here, so I need an enclosed solution. alan
Re: RL02 Tracking
On 22 December 2020 at 10:33 GMT, Aaron Jackson via cctalk wrote: > On 22 December 2020 at 08:01 GMT, Christian Corti via cctalk wrote: > >> On Mon, 21 Dec 2020, Aaron Jackson wrote: >>> The status currently is that the heads will load, and the ready lamp >>> flashes as the heads wobble back and forth very slightly, trying to lock >>> onto the outer servo guard band. Probing TP2 of the read/write module, I >>> can see the S1 servo burst flash (roughly in time with the ready >>> lamp). If I disconnect power to the servo motor, I can manually move the >>> head onto the outer guard band (less than a mm away) and monitoring the >>> position signal (TP15 on the drive logic module) shows this to be close >>> to 0. So, I'm very confused. >> >> I've had almost the identical problem with a RL02 drive from a friend. It >> would start and load the heads, but the ready light would flicker or not >> even come on. After a measuring session I discovered that if I manually >> select the other head, everything would be fine. And if I disabled the >> servo motor I could manually lock onto the track on side 0, but then side >> 1 was out of alignment. So the alignment between the two heads was wrong >> and I had then aligned one of the heads so that the two would lock onto >> their corresponding track. The drive works fine since then. >> > > That's very interesting to know. Thanks! I have already performed the > head alignment and they looked well aligned when switching between the > two heads, but I didn't have any luck getting it to lock onto the first > track with the head select jumper in. I'll mess about with this some > more, it is at least reassuring that someone elses drive has displayed > similar behaviour. > Alright been playing around with that for an hour or so. I think I'm beginning to understand what has happened. The ready lamp flashes not when the servo burst is visible, but when the heads are just before it. Why? Well, I probably set the gain too high on the read/write module. ... Why did I set the gain too high? Probably both my cartridges are weak and to compensate for this, I set the read/write module's amplitude too high during the "Read Signal Amplitude Adjustment" in Chapter 3 of the tech manual. I think having this amplitude too high amplifies the noise too much, which makes the drive believe it's found the first track, but is struggling to read the servo bursts because they're not actually there there, hence the slight head oscillation. Does this sound like a reasonable theory? If so, I suppose now might be a reasonable time to ask the list if anyone in the UK has a known *good* cartridge which they'd mind selling me for a sensible price? I know there aren't too many of them floating about the UK these days. Thanks everyone who has given me some pointers so far Aaron This message and any attachment are intended solely for the addressee and may contain confidential information. If you have received this message in error, please contact the sender and delete the email and attachment. Any views or opinions expressed by the author of this email do not necessarily reflect the views of the University of Nottingham. Email communications with the University of Nottingham may be monitored where permitted by law.
Re: RL02 Tracking
On 22 December 2020 at 08:01 GMT, Christian Corti via cctalk wrote: > On Mon, 21 Dec 2020, Aaron Jackson wrote: >> The status currently is that the heads will load, and the ready lamp >> flashes as the heads wobble back and forth very slightly, trying to lock >> onto the outer servo guard band. Probing TP2 of the read/write module, I >> can see the S1 servo burst flash (roughly in time with the ready >> lamp). If I disconnect power to the servo motor, I can manually move the >> head onto the outer guard band (less than a mm away) and monitoring the >> position signal (TP15 on the drive logic module) shows this to be close >> to 0. So, I'm very confused. > > I've had almost the identical problem with a RL02 drive from a friend. It > would start and load the heads, but the ready light would flicker or not > even come on. After a measuring session I discovered that if I manually > select the other head, everything would be fine. And if I disabled the > servo motor I could manually lock onto the track on side 0, but then side > 1 was out of alignment. So the alignment between the two heads was wrong > and I had then aligned one of the heads so that the two would lock onto > their corresponding track. The drive works fine since then. > > Christian That's very interesting to know. Thanks! I have already performed the head alignment and they looked well aligned when switching between the two heads, but I didn't have any luck getting it to lock onto the first track with the head select jumper in. I'll mess about with this some more, it is at least reassuring that someone elses drive has displayed similar behaviour. thanks Aaron This message and any attachment are intended solely for the addressee and may contain confidential information. If you have received this message in error, please contact the sender and delete the email and attachment. Any views or opinions expressed by the author of this email do not necessarily reflect the views of the University of Nottingham. Email communications with the University of Nottingham may be monitored where permitted by law.
Re: Keyboard storage
Hello Alan, Am 22.12.2020 um 07:17 schrieb Alan Perry via cctalk : > I have a bunch of Sun keyboards that I need to store more efficiently and > don't want to risk damaging by stacking on top of each other. They are Type > 4s, 5s, and 6s (without the wrist rest), maybe 10 in total. Anyone here know > of a box or boxes that would work well for this? I’m storing keyboards openly in a shelf, vertical, standing on the small edge. I alternate them front-back so the slope of the keys array is compensating itself. Aside from some dust, the packing density is really good. :wq! PoC
Re: RL02 Tracking
On Mon, 21 Dec 2020, Aaron Jackson wrote: The status currently is that the heads will load, and the ready lamp flashes as the heads wobble back and forth very slightly, trying to lock onto the outer servo guard band. Probing TP2 of the read/write module, I can see the S1 servo burst flash (roughly in time with the ready lamp). If I disconnect power to the servo motor, I can manually move the head onto the outer guard band (less than a mm away) and monitoring the position signal (TP15 on the drive logic module) shows this to be close to 0. So, I'm very confused. I've had almost the identical problem with a RL02 drive from a friend. It would start and load the heads, but the ready light would flicker or not even come on. After a measuring session I discovered that if I manually select the other head, everything would be fine. And if I disabled the servo motor I could manually lock onto the track on side 0, but then side 1 was out of alignment. So the alignment between the two heads was wrong and I had then aligned one of the heads so that the two would lock onto their corresponding track. The drive works fine since then. Christian
