Someone is going to say it sooner or later, but half tracks are supposed to be as near zero as possible, not 100. Also, you should only test aligment with a factory made disk like 1541 Demo disk. There needs to be a reference point and what better than a Commodore made factory disk, align to that and all i well. :) Great channel, i watch all your videos please keep the coming. 👍

@JanBeta

3 жыл бұрын

Ha, you are completely correct of course! I just assumed it would be the correct value because every half track read the same... shame on me. The drive works perfectly fine, I wonder if the -100% reading is caused by the C model in some way? The on-track alignment seems to be spot on so it would not really make sense for the half tracks to be completely off, I guess. Strange. Thanks for pointing that out, though!

@danielmantione

3 жыл бұрын

@@JanBeta Try different disks, preferably ones created by drives you know are aligned well (original 1541 demo disks are a good choice). You may/will get different results between disks. If the -100% is consistent with different disks, the drive is not perfectly aligned, but still good enough not to cause trouble.

@josesmith6009

3 жыл бұрын

@@JanBeta You would need a disk written with the half tracks in addition to the standard tracks. This would be a specifically written alignment calibration disk. Regular commercial disks, including the Commodore 1541 test disk, aren't written with half-tracks. These calibration disks were not written on 1541 hardware but on other equipment. They aren't easy to come by these days, but I believe the FreeSpirit alignment software that shows up on eBay has an alignment calibration disk written on the back side of the disk. Although, I don't like the FreeSpirit software or alignment system, it is a way to get a calibration disk written with both standard and half-tracks. You can run the alignment test on a factory disk such as the 1541 test demo disk and get a good idea if the drive is in alignment, but you just need to ignore the last column of data and only pay attention to the column of data that shows green and 100 for you in the video.

@mertuckan

3 жыл бұрын

@@JanBeta bad is red, good is green

@alessandromarani101

10 ай бұрын

Why near to zero? 100% green AND 100% red is perfect. This means green 100% read success on tracks and red 100% fail between tracks, which is perfectly aligned.

Do I own a Commodore? No. Have I ever owned a Commodore? No. Did I still watch the whole video anyway? Yes, because watching Jan Beta work on anything is a joy!

Where I live, the ancient overhead wiring has fun with the supplied voltage, sometimes it's the UK full-fat 240 volts, sometimes it drops down to as low as around 210 volts, causing my UPSes to kick in their AVR functions to nudge it back up, but that said, the voltages officially only changed on paper, as it would have meant ripping out loads of expensive transformers and substations and whatnot to comply, so the european standard of 230 volts has that tolerance of +10/-6%, which pretty much covers the voltages that already existed, so it was just a paper-pushing exercise to spend money where it wasn't actually needed... :)

Hi Jan! An alternative idea that is literally as "cool" as possible: modify the 1541 to use DC power input only and have the PSU completely external to the 1541 like the 1541-II. If anyone's interested, example in my video "Commodore 1541-DC: a 1541 mod for DC power, like the 1541-II". For the original 1541 a heavy duty "dual" PSU can then power both the 1541 and C64: "Electroware C64 PSU heavy-duty mod (30W DC power)" I wonder if a typical modern "2-in-1" or dual PSU could power the 1541C with the newer drive mechanism that might need less power. That would be nice!

@JanBeta

3 жыл бұрын

Nice idea! I think I even watched your video already. Makes sense for an elegant setup with a single power supply. :)

@DrDavesDiversions

3 жыл бұрын

@@JanBeta If you or someone decides to do this from scratch the "lazy way" as you say in your "Building a DIY C64 Power Supply (The Lazy Way)", somewhat like my modded Electroware 2-in-1 PSU for heavy duty, it looks like the 30 watt MeanWell IRM-30-5 and an SD XMDZ DC-DC boost converter added to Sven Peterson's "C64-PSU-Global" design should work well to additionally power any 1541. (I see some examples where that desing used the lowly Mean Well IRM-10-5, but the 30W version is just a few euros more.)

The change in heat dissipated by the regulator will be more than the change in the input voltage to the regulator. If the transformer outputs 15V and you're regulating that to 12V, the regulator only converts the 3V drop into heat (times the current, but we're talking about ratios right now so that's not important). The rest of the heat is emitted by the circuit you're powering and that stays constant. Reducing a 15V transformer output to 14.5V would then change the voltage drop through the regulator from 3V to 2.5V, which is a much larger percentage change than the percentage change in the input voltage -- 15V to 14.5V is around a 3% change in input voltage, but the corresponding change from a 3V drop to 2.5V means almost a 17% change in heat dissipated in the regulator. So even though this seems like a trivial change it makes sense that it would have a significant effect!

@JanBeta

3 жыл бұрын

Yes, makes sense! It definitely changed the temperature quite a bit. :)

Thanks for demonstrating these mods Jan.

Always excellent video!

Jan is back!

Well done! :) I actually removed all of the power supply on my 1541 and replaced it with a modern MeanWell PSU, and now it's running totally cool and is much lighter. :)

The harmonisation of European mains voltages was simply a mathematical exercise where the tolerance was increased in stages. The supply equipment was not changed. The IEC 60038 standard is 230V AC (RMS) with a tolerance of +/- 10%. The UK is officially on the previous harmonisation step at 230V with an asymmetric tolerance of -6%/+10% and in practice the domestic voltage will still be around 240V.

@JanBeta

3 жыл бұрын

Yes, it definitely was a mathematical thing in the beginning. Mains voltage in Germany is spot on 230V in most parts nowadays, afaik. Very stable and not much fluctuation at all. It used to be a lot different back in the day. :)

@CyclingSteve

3 жыл бұрын

@@JanBeta It's a design standardisation, the idea is you don't produce electrical equipment that works in your own country but not for your neighbour (or overheats as we have seen). We could all design to 230V, but it's far better to know it needs a -6%/+10% tolerance.

Ciao Jan,hai fatto un bellissimo lavoro con la modifica al drive 1541.sono molto contento di averti visto,sei il miglior tecnico che ci sia.al prossimo video Jan,ciao.

Cool video, I had no clue that Germany had changed the voltages over time. That must have been a painful transition in some ways. It is always fun seeing you dive into apiece of hardware and try to decipher it's history of mods!

@JanBeta

3 жыл бұрын

I have more plans for the drive. Currently working on getting SpeedDOS in which I suppose was the fast loader installed previously. :)

UK Voltage is still commonly referred to as 240V but it's set out in "The Electricity Safety, Quality and Continuity Regulations 2002" as 230V +10% -6%.

@fluxington

3 жыл бұрын

Not just referred to as 240V. It actually still is 240V. On a good evening with low local loading, it's not unusual to see 245 to 248 Volts.

@ches74

3 жыл бұрын

@@fluxington It's actually +10% which I just corrected above. So the voltage can be anywhere from 226V to 253V. I agree that the supply does tend towards the top end but that is to be expected as the infrastructure was in place, not worth messing with. Officially it's 230V with tolerance but nothing substantive changed with the regulation.

@blenderbuch

3 жыл бұрын

For science it would have been nice to measure the transformer voltage before rewireing 😜

@fluxington

3 жыл бұрын

@@ches74 Yes and of course it depends on time of day and system load, tap changer positions and how close you are to a secondary substation. I believe the tolerance was changed from 6% to 10% to incorporate the harmonisation without any actual changes to the system!

@DavePoo

3 жыл бұрын

I measured mine just now at 243V

Great idea ! Thanks for the mod tips. We have 240Vac in Norway. I "changed the taps" on a transformer in a radio once too for 240V. I suppose my 1541 drives are running hotter than they need to be if they are configured for 220Vac.

From the UK... Nominally 230v lots still at 240v but with a rather wide margin. I get around 250V at the wall which causes me issues as I build valve amplifiers and they can sound different in a house at 230v. The recording on my channel are at 250v. Vintage computers like the PET4032 video I have done on my channel also work fine.

@Jan Beta - Ideally you should be doing the compressed air blast _before_ any manual cleaning and lubrication. Otherwise you could easily be kicking up dust and junk that lands on what you just cleaned and lubricated.

@JanBeta

3 жыл бұрын

Yes, didn't think of that this time. But I had it relatively clean already before I did the lubrication. Just noticed some remaining dust bunnies and styrofoam pieces in the bottom case too late. :D

The power socket is an IEC C14. The plug that goes in it is a C13.

As you say, it should be okay with a 10% tolerance on the psu. In the UK it's usually around 240ish and I’ve never measured 230v. Apparently 230v was never implemented in the UK and many items often say 220-250v.

Listen, Jan. If you are running out of stuff that needs fixing I can easily send more. Just drop me a discord message. :P

33:07 - "Remember to subscribe to the bell and ring the thumbs up button" 🤣🤣🤣 as always love your work keep it up Jan!

Honestly I was not aware you could do this sort of mod to one of those, I gotta point a friend of mine to here so he can do this as well he got one of these and it's likely completely original, by that I mean never opened until now and untouched inside, and this might help his disk drive not burn out so fast until he can maybe fix it up, Danke Jan!

Wow I never heard of this mod. A really good original alternative to a complete psu replacement

You could play a song with the drive music software. The stepper motor coils sounds very nice in those days.

In Europe, the mains voltage is 230 V ± 23 V with a mains frequency of 50 Hz ± 0.2 Hz. Without wanting to downplay your work (which is praiseworthy and shows the true conservator) one could think, with the above tolerances, that it is a fight against windmills to make this adjustment. A switching converter based power supply(may introduce other problems). Or a more specified linear regulator. But above all, adequate cooling. This is the most important thing (thanks commodore...) in order to increase the service life, not only of the voltage regulator but also the reliability of the subsequent components. In addition, this part should also be able to do its job: regulating the voltage. According to the data sheet, the input voltage must be a certain value above the regulated target output voltage, and an LDO regulator requires less ΔU than these old TO-3 monsters. If these values ​​are not correct, the electronics will not work reliably either. Sporadic failures and hard-to-understand errors are the result. Incidentally, the heat loss is not an annoying evil, but a necessary consequence to fulfill the purpose of voltage regulation. The implications: 220V to 230V with a transmission factor on the low-voltage side only results in 4% more heat (all approximations). The tolerances for the mains voltage are 20%. Just think about it. The second tap on the transformer now causes a 5% reduction in the secondary voltage. You should check whether this is permissible for the two LM340 in the circuit (with the mains voltage tolerances). These are just a few thoughts on the specs. In practice: I would do it just like you! And thanks for the video:) The schematics are terrible by the way. Do you have a reliable type specification for the built-in transformer? Without load you measured W1: 9,7VAC and W2: 15.5VAC. With what primary voltage? Any numbers or nameplates? I would be interested in that or measurements(caution mains voltage! at least both pre-regulated voltages before and after the bridge-rectifiers. Measured under load.), Jan. There is also an article at Hackaday "Commodore 1541 PSU replacement", with a total PSU replacement. Can't link, please use google. KZread is f'd up. P.S.: In my "Das große Floppy Buch" there isn't even a 1541 circuit diagram. Data Becker, pfff.

Back in the day we called that clattering noise 'woodpeckering' we used to stick a small pad to the head stop to make it quieter.

Lot of old US devices show 110 volts as back in the 80's the switch to 120 volts started. The US is confusing as we use a center tapped transformer feeding the homes which produces 240 volts on the outer taps and 120/120 from the center to each side 180 deg out of phase. We only use the 240 for the larger appliances unlike many other countries.

My 1541 was running toasty warm to the point where the case got darker - back in the 1980s when the mains voltage was still 220V. I also blame a fried rectifier to the excessive heat. I changed it to 240V and haven't had any PSU-related repair on that drive for the following 30 odd years and the eventual change of the voltage Now that the main voltage in continental Europe has been raised to 230V the mod has become almost mandatory. Not sure if Commodore has modfied the PSU of the 1541 over the product lifetime though.

yes its 240v 50 HZ in the uk

You could hook up that track zero sensor. On the 15 pin connector, purple goes in pin 4, white goes in pin 5 and blue wire goes in pin6. Burn an eprom and you're good to go.

8:30 Some old UK equipment says 250volts, The standard that everyone says is 240 volts, but I'm fairly sure the UK also uses 230 volts.

Nice Video, Jan. About the Track 0 Sensor, I seem to remember reading in magazine at the time that they disabled it from the factory. Like you stated there is a jumper to enable it. Seems you have a unique one if it is missing. I have 2 1541C drives and one I bought when it was new back then. It of course rattles but not nearly as loud as earlier 1541s. I bought a second one and I chose to enable the sensor a few years back to see if it really made a difference in compatibility. I haven't come across anything that didn't work on it fine so maybe it was some rare situation and they played it safe? The 1541C ROM is for sure unique that it I guess must support the sensor. Like you I have read about others swapping in the 1541-II ROM to put the head knock back to what it was in previous models. Personally I like the sensor. The 1571 also has one and that was always enabled so I am not sure what the problem is.

Jan hi. it was a very beautifull presentation. Explanatory in depth and very cool for the life of 1541 floppy drivers. We in Greece have 220 volt. If i make this change will i still have better results or will i have some malfunctions? Good luck my friend and good health always.

I wish you'd done a before/after metering of the power draw. Any drop in heat would have shown up as a drop in power usage at the mains plug. It would have quantified any concrete difference in the mod!

Danke für die Info! Das war mir völlig neu,muss ich direkt mal nachsehen ob meine 1541 Laufwerke auch so einen Trafo haben :)

@JanBeta

3 жыл бұрын

Die 1541s, die ich hier habe, haben alle einen Trafo, der sich umbauen lässt. Bei den älteren Modellen sind die Anschlüsse am Trafo an der Oberseite, also eher noch einfacher, die umzubauen. Und es lohnt sich auf jeden Fall. :)

@harihegen

3 жыл бұрын

@@JanBeta danke :)

I'm surprised that it's actually sensitive to the difference between 220v and 240v. Over here in America the standard has crept over time from 110 up to 117 to 120 but even with the standard being 120, some homes can have electrical service as high as 125, so in general, devices here are pretty happy running anywhere between 110 and 125.

@hansihinterseher9156

2 жыл бұрын

They are not really sensitive. I've never modded my drives and they have been woking fine with 230 V for years. But of course cooler - even if only a bit - is better.

love it

Morning. Thanks for the entertainment.

@JanBeta

3 жыл бұрын

Morning! You are very welcome, hope you enjoy!

I did this a long time ago to my VC-1541. It runs a bit cooler.

That wasn’t the only floppy drive to make a funny noise because it didn’t have a track-0 sensor; the Apple Disk ][ drive was (in)famous for that, too. There were probably others as well. 😊

Good Morning!

@JanBeta

3 жыл бұрын

Mornings!

It would be great to build a modern replacement PSU for the 1541, just as u did with the C64 PSU; the massive weight of the 1541 transformer and the power consumption are 2 big drags; also if those linear regulators fail they would probably fry the precious ICs, including the 6502 cpu

We often see anywhere from 230-250 and I've seen nearly 252-255v a few times depending on the time/load on the local grid etc

@nednettapp

3 жыл бұрын

Who is We?

Great video Jan, i didn't know that 1541 transformers can be rewired. I will mod one of mine with a modern psu. How about a track display mod video? I am very curios about them.

Hi Jan. Is it possible to tranfer the transformer outside of the case in order to make the drive cooler?

@mibnsharpals

3 жыл бұрын

you does not need tranfer the transforme out, it would be not so warm. The problem is the 5V regulator. do that hack or if you have experience, replace the analog regulator with a switching regulator. In the 1541 the regulator has an efficiency of less than 50%. With a switched controller, it increases to 70 - 90%, depending on which model you are installing.

Can you retro bight the front? I had the exact same drive. The face plate was the same color and the case.

@JanBeta

3 жыл бұрын

I think some of the early models had a painted front part but on the later ones, it can most likely be retrobrighted. I’m going to try it sometime for sure.

UK standards can be helpful occasionally! lmao never realised everyone merged towards 230v .... Whilst in Japan they have some 50hz and some 60hz haha

I have 2 of them. Both working fine but somehow one has sometimes more difficuties ready a floppy. My friend has also the same drive but it doesn’t want to read. Head goes to track 18 and back again and stops. I can not fix that problem.

Would it be feasible to replace the linear regulators with switching regulators and keep the transformer? That way it would be almost original, just with more efficient regulators which wouldn't dissipate as much heat.

@jeroentaverne8232

3 жыл бұрын

Traco and WE has replacements for the 7805 and 7812 which are switched regulators. Not sure if they provide enough power.

@dreamvisionary

3 жыл бұрын

@@jeroentaverne8232, I've used Traco in the past but not in a 1541. There's already a video showing the transformer being removed and replaced with a switching supply without the need for regulators but would be interesting to see one with the transformer remaining and the regulators changed for switching.

Just picked up one of these drives from eBay, and yep, mine does the rat-a-tat-tat on startup & when formatting a disk... guess I better crack it open and see if it has that jumper for the track zero sensor.

@JanBeta

3 жыл бұрын

That should fix the "issue". Commodore seems to have shipped many 1541Cs with the sensor deactivated (maybe to maintain compatibility? Who knows!). Depending on the ROM you have in yours, you might have to replace that, too. Afaik the original 1541 ROM doesn't support the sensor at all.

I fixed my C64 (again lol) while watching this video. Just needed de-oxit (contact cleaner) in the cartridge port. My 1541 Ultimate 2+ cart wasn't working. It was booting to BASIC (which it shouldn't do) and when I hit the menu button I got a screen full of corruption. Now it's working fine! I had to steal the USB drive to install windows 10 on my new computer since it's the only USB drive I have that's big enough. When I put it back in the U2+ had issues. I've put de-oxit in there before. I wonder why it had issues again.

@JanBeta

3 жыл бұрын

Yeah, the cartridge ports not making good contact is a very common problem on the C64s. I've had those issues a number of times. I usually spray contact cleaner in one of my cartridges and slide it in and out of the connector a couple of times. That makes it at least work for troubleshooting most of the times. A pencil eraser and some alcohol on the PCB edge are great for completely deep-cleaning the ports!

Hola! Buen día!

@JanBeta

3 жыл бұрын

Buen dia! :)

Hallo Jan. Could you make a video like this one about the C1571? MfG, Pedders. PS - If I can make a suggestion, I reckon some schematics would make the mod easier to follow.

I am in Malta and we have 240v but one of my 1541 is from Germany 220v. I've been using it fine but should I fix it for 240 ?

@JanBeta

3 жыл бұрын

It would definitely make it run a bit cooler, so I'd do it. If you really want to bring the temperature down, adding a switching power supply is the best option of course.

1541 liebevoll diskröstgerät genannt / english : disktoaster. I would replace the analog 5V regulator to an switching one. After that it will be much cooler.

That disk would be very nice with a aldi 64

5:10 The color is called beige.

@JanBeta

3 жыл бұрын

I mean the color of the original breadbins/1541s. It's not quite beige but a bit darker. :)

@MacMelmac

3 жыл бұрын

@@JanBeta Meatloaf coloured. 😄

Jan, you really should have measured the voltage going into the into the regulator before and after. Then you could have calculated the power being dropped by the regulators. How about replacing them with buck converters?

🤘😁🤘

We didn't transition to 230VAC at all. The spec was changed but when I put my Multimeter in my Outlet, it still says 220V. That might have something to do with the Brits, who indeed have 240VAC. PS: I'M only about 100km from you :)

@danielmantione

3 жыл бұрын

Originally Europe was harmonized to 230V +/- 10%, later this was tightened to 230V +/- 7%. This means that a outlet that produces 220V is still compliant with specifications today. No need to fix stuff that ain't broken. That said, in many places of Europe, the voltage did chance, but if you design anything new, you design it to the modern specifications.

@Stefan_Payne

3 жыл бұрын

@@danielmantione yeah, pretty much. It was a Harmonization of the spec that let us put the same voltage on the box across Europe... But weren't the Brits the only outliers anyway?? (well, they have 32A Circuits as Default, which is why they need fused Plugs)

I've seen people mod these by taking out the transformer and linear regulator IC's, and patching a switchmode 5v/12v supply in there. Probably what I would do if I wanted to keep one :)

@evensgrey

3 жыл бұрын

A particularly good idea when you consider that those might be Commodore's infamous 5V regulators that fail by shorting the input to the output and frying everything on the 5V rail. It will also help the damn thing run a LOT cooler and make the infamously heavy drive a lot lighter.

@jaycee1980

3 жыл бұрын

@@evensgrey these are LM340K's i think which are quite robust.. unlike some of the cheap 7805's that were in the old power bricks

Looks like your track zero sensor is not connected to the motherboard at all. You can see the white/purple/blue wires from the sensor just lying (10:13 you can see them at the bottom of the frame) at the bottom of the case.

@danieltufvesson1349

3 жыл бұрын

I noticed this also. Normally these wires are connected to the big P3 connector. On all 1541C I have seen the track zero sensor has been deactivated from factory. Cutting jumper J3 enables it if the ROM supports it (I think it is supported in 251968-01 EDIT: yes, and in -02 as well). I suspect this drive was modified at some point with another ROM from a standard 1541 to gain better compatibility. However there is never a need to physically disconnect the sensor cables from the P3 connector so I don't know what was going on here.

@JanBeta

3 жыл бұрын

Yes, you are completely correct! The wires are just disconnected, just double-checked that myself. I think the ROM must be modified to not use the sensor. A bit confusing, but it makes sense. The ROM seems to match a SpeedDOS ROM for the 1541-II with some slight changes. I am going to investigate further soon.

@JanBeta

3 жыл бұрын

I think the drive had SpeedDOS installed which requires the sensor to be deactivated. Usually people just cut the connection to the sensor on the VIA that is used for the parallel cable but the previous owner seems to have disconnected the sensor completely. Which should have the same effect.

You could even insert a voltage selector circuit on this one... 110, 220, 240... only the 50hz tho

@JanBeta

3 жыл бұрын

Yes, you could wire something up. For the 110 you'd need another transformer though. Regarding 60Hz/50Hz it should not matter, as all the voltages are rectified and converted to DC anyway.

Yeah still 240v in UK, didn't they just change the allowed tolerance and not actually change the voltages?

I may have missed something, Jan, but why does your monitor say LIPS on it?

@jabbawok944

3 жыл бұрын

The small one is a Philips and Jan covered up the Phi with tape. I guess the sticker on the big tv it’s a homage to that.

@JanBeta

3 жыл бұрын

Yes, some people missed the LIPS logo from the old monitor (which is actually still set up but moved to the side of the lab). :)

@jabbawok944

3 жыл бұрын

@@JanBeta I miss Pinkie-Pie.

The 1541 is kind of cool but they're so ridiculously huge that they're simultaneously uncool!

@JanBeta

3 жыл бұрын

Yeah, I suppose they could have shrunk it down quite a bit at least for the newer models with the shorter PCBs. But, hey, it's Commodore, so they cut cost and kept using the original design and case moulds for a long time, I guess. :D

@ches74

3 жыл бұрын

@Jan Beta Commodore limited themselves by using their poorly designed serial bus and therefore needing to put serious computing power in the drive itself. The 1571 was slimmer I think but heat and all the hardware are the issues. It's hard to understand why they didn't somehow update to have a proper disc interface that ran at sensible speeds. Everything after that initial decision was a sticking plaster. Somehow the machine had enough charm for people to look past the shortcomings but it still seems a strange and risky strategy.

@ches74

3 жыл бұрын

@@JanBeta "Are you keeping up with the Commodore?" 🤦‍♂️😂 Can't say they didn't do alright.

@ches74

3 жыл бұрын

@@malkogindrat I still kind of want one even though it's ridiculous! 😉 Nearly bought one even though I don't have a C64.

I am really not sure if this is really needed, or something that I would have done like 30 years ago on my 1541 in a bout of perfectionism. After all the drives have worked for so long with the heat. I might check my own one for that 240V tab, which is a 1541 with ALPS drive. Also I am not a fan of replacing the transformer and the two 7812 and 7805s. Switchmode power supplies are notoriously bad about high frequency ripple and their sniffer circuits (HF suppressor circuit) on those chinese PSUs are often sloppy in design. Also in case one of the capacitor blows it would spew it's electrolyte against the underside of the precious 1541 board which is often NOT shielded or protected. IF you do tho please cover the 1541 PCB's underside with some plastic foil. I just believe a simple transformer is way more reliable than a low or medium quality switchmode PSU. That simple assortment of copper coils and steel core that a transformer is could easily go another 30 years. But switchmode PSU?... hum. Grüße aus Hannover vor einem alten C64, C128 und Amiga-user und Bastler von damals!

Jan, I just modified the exact same drive (minus the eeprom) last week with a switching supply. Would you want the parts (rectifiers, giant caps)? I’d just ship it your way. The transformer is North American, so less valuable for you.

⭐⭐⭐⭐⭐

need replacing the trantransformer with smps 12v/5v and it work better and safety

here in England it is v240

Shouldn't the last column be zero in perfect alignment? If I understood it correctly, -100 would be fully reading the previous full track, +100 would be fully reading the next full track. Ideally, it should be zero (no previous full track, no next full track, just half-track the head is over at the moment). "Fourth column is between tracks (or half tracks), this value can fluctuate a bit even on a well aligned drive. The 1541 allows for some tolerance and therefore some values can be within reasonable limits."

@JanBeta

3 жыл бұрын

Yes, that column should be close to zero according to the documentation. Strangely, it is very close to -100 on all my drives I have checked except my 1541-II. I wonder if it's an issue with the software not detecting correctly for some 1541 versions. They all do work fine as far as I can tell (also with copy-protected disks that use the half-tracks). I am going to investigate further.

JiffyDOS! JiffyDOS! Let it have the JiffyDOS!

@JanBeta

3 жыл бұрын

I actually just JiffyDOSed my 1541-II and it works like a charm. Might do that to this one, too, at some point. :)

@ownpj

3 жыл бұрын

This drive has the light sensor so combined with the correct ROM it will never head-rattle under normal kernal routines. This means it will stay in alignment longer than another drive would. Jiffydos requires a paid license and unless there is a specific 1541C version you're just going to introduce head-rattle and prematurely ruin the alignment. Personally I would use the stock 1541C ROM on this drive. Save the fastloading mods for your other drives.

Your ROM doesn't match any other ROM I could find. It starts like 1541C.251968-01 but the further down you scroll the more the differences.

@JanBeta

3 жыл бұрын

Somebody pointed out in the comments that it's probably some kind of modified SpeedDOS. I am currently looking into reinstalling a parallel cable and trying that out. :)

Put in JiffyDOS ...

@JanBeta

3 жыл бұрын

I just did that with my 1541-II. I have more fun plans for this drive. ;)

The long, flat thingy is probably a resistor (termination) pack; custom glue logic would have either been GAL/PAL, or custom ASICs back then (like the PAL chip in a C64) I’ve even heard of cases where glue logic that implements a lookup table was done as a mask-programmed ROM. 😋

200 dirty volts. That's a lot of dirty volts. ^^

DOOD!

Hello Jan. A few months ago I did something similar on my 1541 floppy drive. My idea was to redo the linear voltage regulators and make new switch mode power supply with KiCad . I wanted the PCBs to be the same shape as the original linear regulators in the TO-3 case. I didn't get the big transformer out either. I just didn't want to change the autenzity of the device. Here is the link to my video: kzread.info/dash/bejne/pKR1x9t8iajWZNI.html Would love to hear from your opinion.

Hello Jan, do you have a 1581 and/or would you be interested in one?

@JanBeta

3 жыл бұрын

Never seen a 1581 in real life, they are pretty rare. But I would love to get hold of one of course. :)

Hi Jan. I also moded my 1541 with an SMPS (Switch Mode Power Supply), if you are interested you can see here.. kzread.info/dash/bejne/fp550dWlk6uqn8Y.html Now it's cooler and lighter! 😉 Greeting and happy easter! Doc 64!

The original C64 color is known a turd...

Why even bother! If you should do something for the heat you should replace it with a switching regulator ...