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logikstate
Account closed
Registered: Jan 2011
Posts: 21 |
1541-II read problem
Is this the right place to post this? Anyhoo, here goes:
I have a whole bunch of 1541's and one 1541-II
I've used an alignment disk and re-aligned the heads and generally cleaned up one of the 1541's and it can format and read back disks and read an original disk I have here without problems.
As for the 1541-II, I cannot read anything on it reliably... Even after cleaning the heads etc... If I format a disk and read it back, there are errors. If I try to read the same original that works on the 1541 there are always errors.
But... If I format a disk on the 1541-II, I can then read it on the 1541 I've cleaned up without problems.
So, the question is, what might be the problem with the 1541-II? I'm kinda baffled at the moment... Was hoping that somebody with a little more knowledge than myself might be able to suggest something I could try.
Thanks in advance for any help and advice!
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ready.
Registered: Feb 2003
Posts: 441 |
I have had the same issue a few years ago, then I noticed the 5V line gave around 6V. Build my own PSU with stable 5V output and all my 1541-II resurrected, no problem ever since. I also tested several original 1541-II PSUs, but sooner or later all gave problems.
http://www.cbm8bit.com/projects/ready/
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logikstate
Account closed
Registered: Jan 2011
Posts: 21 |
Thanks for the info, I will read PSU output with multimeter later today! |
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Frantic
Registered: Mar 2003
Posts: 1647 |
Pretty pretty please someone.. please produce decent stable PSUs for C64 machines and drives and make them available for sale. I really need it. (And I am quite sure a whole bunch of ebayers might buy such stuff as well.) Having that would probably also prevent some of my dear hardware from breaking down in the future.
Am I right if I believe that flakey PSUs may be a major reason for broken C64's in these days? |
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Twoflower
Registered: Jan 2002
Posts: 434 |
Quote: Pretty pretty please someone.. please produce decent stable PSUs for C64 machines and drives and make them available for sale. I really need it. (And I am quite sure a whole bunch of ebayers might buy such stuff as well.) Having that would probably also prevent some of my dear hardware from breaking down in the future.
Am I right if I believe that flakey PSUs may be a major reason for broken C64's in these days?
I think you are perfectly right about that. I have seldom (if ever?) seen a 1541-II break down due to a flakey PSU, though.
On another note - are you saying that you're in need of either a PSU to mod or a 1541-II? I could possibly dig out bring either to you at Datastorm if you require it.
@logikstate:
Just like Ready says, i'm pretty sure that the PSU is to blame. I've done pretty much exactly what he did, and this remedied all the problems I had with my 1541-II's. |
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logikstate
Account closed
Registered: Jan 2011
Posts: 21 |
There is an Ebayer in the USA that manufactures multi-PSU that powers C64, 1541 and 1541-II from one power brick... They are multi-voltage/multi-region too... I've been meaning to order one as I'm pretty sure that my C64 PSU is not great and I only use it in 30 minute sessions.
I will find his details out and see if he is still making them.
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logikstate
Account closed
Registered: Jan 2011
Posts: 21 |
Here is a link to the triple PSU I mentioned (this is an old listing which has ended)... I believe he makes them to order so if you contact him I'm sure he would be able to help.
http://www.ebay.com/itm/COMMODORE-C64-64C-1541-1541II-1581-Cust..
I'm probably going to have to order one myself... The old PSU's now seem to suffer from capacitor problems and over/under volting... I still need to test the voltage to confirm on my 1541-II but it sounds like this is the most likely problem. |
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ready.
Registered: Feb 2003
Posts: 441 |
usually 1541-II don't break due to bad PSU (unless the PSU give real high voltage), but just doesn't work well. C64s are more prone to failure due to overvoltage, RAMs are the ones to blow first (they are the less tolerant, I think the datasheet says no more than 5.5 V, while SID, VIC, CIA, can handle up to 6 or 7 V if I remeber right).
Anyhow the issue with selling new PSUs nowadays is that it is illegal to sell it without a certification (it's an 220V or 120V device!), and certifiaction costs a lot. |
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Frantic
Registered: Mar 2003
Posts: 1647 |
Don't want to hijack the thread but just wanted to say thanks to Twoflower and logikstate for your replies. I have actually placed an order for one of those PSUs now. Exactly what I need. (Not coming to datastorm btw.) |
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ready.
Registered: Feb 2003
Posts: 441 |
I remeber a post on Lemon forum about this
basicwayne guy selling PSU replacements for Commodore computers (see ebay link above). A Lemon user got one of these PSUs and it was total crap: assembly was poor, it produced a lot of heat and so on. Here's the post:
http://www.lemon64.com/forum/viewtopic.php?t=33023
Personally I have no experience with this guy, as I built my own heavy duty PSU which works real well (those who were a X2012 might have seen it). |
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logikstate
Account closed
Registered: Jan 2011
Posts: 21 |
Hmmmmm... Good info to know... I may still order one and inspect and modify it myself...
I'm not sure if I like the idea of a metal switch on a high voltage PSU.
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logikstate
Account closed
Registered: Jan 2011
Posts: 21 |
I'm reading 7.2v off the 5v line whilst its under load, connected to the 1541-II via probing the back of the power connector... I'm also reading 12.3v of the 12v line... I guess that's possibly ok? the 5v is WAY out though!
I guess its the PSU then!
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ready.
Registered: Feb 2003
Posts: 441 |
12.3V should be ok, but those 7.2V on the 5V line is way too much. Yep, PSU is gone. |
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maestro
Registered: Mar 2004
Posts: 727 |
i just made my own psu cost £10 and about 30 mins of work. 1541-2 has been superb ever since. |
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HCL
Registered: Feb 2003
Posts: 727 |
Quote: i just made my own psu cost £10 and about 30 mins of work. 1541-2 has been superb ever since.
Very interesting.. I currently have 2 drives, but only one PSU which seems to be worn out now :(. Any chance you could explain how you made your own? What components did you buy etc..
Other ways to get a working PSU are also very welcome.. |
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Frantic
Registered: Mar 2003
Posts: 1647 |
EDIT: Nothing |
