English Amiga Board


Go Back   English Amiga Board > Support > support.Hardware

 
 
Thread Tools
Old 05 April 2002, 15:25   #1
Bloodwych
Moderator

Bloodwych's Avatar
 
Join Date: Jun 2001
Location: I'm behind you!
Posts: 3,763
Technical question on 3.5" HD and Amiga 1200

I want to replace my 3.5" HD in my 1200 with a larger model, but I'm not sure if the standard PSU will handle the larger drives current draw. The standard PSU specs are:

Total 25W

+12V 500mA = 6W
+5 3A = 15W
-12V 100mA = 1.2W

Currently I have an IBM 330MB 3.5" HD in my 1200 with the following power requirements:



RPM=3800


I slaped this baby in 10 years ago and everything is still going strong.

Recently I purchased a 2GB seagate HD to replace my IBM. These 3.5" drives are ideal for 1200's because they're so small. Compare these physical specs:

IBM 3.5" & every other brand: Ht 25.4mm, Wd 101.6mm, L 146mm
Seagate 3.5": Ht 19mm, Wd 102.1mm, L 127mm

I had quite a bit of trouble with the hieght of the IBM, but the seagate slips in the 1200 like it was made to fit. The only thing left to worry about is the power requirements. Luckily I also have an old PC with a 1.28GB seagate HD, so I can basically place either the 2Gb or the 1Gb seagate hard drive in my 1200.

The reason I'm sticking to 3.5" drives is because I've already got all the leads and done the required mod to make them fit.

Here's the specs for the 1.28GB:



RPM = 5200


and the 2.11GB:



RPM= 5200


Questions:

Can anyone tell me which one I should choose?
Will the current draw be too high for the standard PSU?
Will the drive spinup fast enough for the 1200 to boot on second attempt (like my IBM does at the moment)?

Looking at the specs myself, the 2.11GB appears to be a bit power hungry.

Thanks for anyone’s help, much appreciated!

Last edited by Bloodwych; 05 April 2002 at 15:37.
Bloodwych is offline  
Old 05 April 2002, 21:07   #2
jmmijo
Junior Member
jmmijo's Avatar
 
Join Date: Jan 2002
Location: PDX
Age: 59
Posts: 2,380
How about a second AT/ATX PC power supply just to power the hard drive? Use a power strip or something like this to synchronize when the power to the entire unit is turned on.
jmmijo is offline  
Old 06 April 2002, 03:38   #3
ElectroBlaster
Junior Member
ElectroBlaster's Avatar
 
Join Date: Mar 2002
Location: Exeter, Devon, UK
Age: 47
Posts: 1,594
Send a message via ICQ to ElectroBlaster
Hi!

What you need is one of those old heavy a500 psu's that pump out 60watts! i have an a1200 with a quantum fireball 5400rpm 2gb drive running with that 60watter no problems at all

if you cant get one.. get an AT pc power supply and mod a spare amiga power lead into it! imagine 250watts of spare power
if you need any help with this then please e-mail me as i have done dozens of these psu's

J
ElectroBlaster is offline  
Old 06 April 2002, 11:28   #4
Bloodwych
Moderator

Bloodwych's Avatar
 
Join Date: Jun 2001
Location: I'm behind you!
Posts: 3,763
Is this the old PSU you've mentioned:

Linko

Why were they rated so high for an A500?

My A1200 supply is the heavy version as well, but it definately only mentions 25W.

As for converting a PC PSU, the only one I've got lying around spare is an ATX but these don't have switches like the AT.
Bloodwych is offline  
Old 06 April 2002, 13:53   #5
poppe
Junior Member
poppe's Avatar
 
Join Date: Apr 2001
Location: Umeå
Age: 43
Posts: 195
Send a message via ICQ to poppe
..just go to a computershop and buy a used pc psu. they go (at least in sweden) for around £10 or something and then you will have all the power you need. Just cut the cables and reconnect them right. I did that for about 5 years ago and it still runs like i kitten...

And it´s good having spare hd/cdrom connectors outside if you are using alot of internal hardware in an "external way".

Last edited by poppe; 06 April 2002 at 14:00.
poppe is offline  
Old 07 April 2002, 00:11   #6
ElectroBlaster
Junior Member
ElectroBlaster's Avatar
 
Join Date: Mar 2002
Location: Exeter, Devon, UK
Age: 47
Posts: 1,594
Send a message via ICQ to ElectroBlaster
Quote:
Bloodwych
That link you posted is exactly what i was on about! it must be the dark biege-type! e-mail them to make sure its a 65watter..

the heavy a1200 white one isnt up to the job! the dam thing is filled up with some kind of epoxy resin for which i cannot see the point as it makes the thing so hot its stupid! it just burns out quicker that way *makes a good paper weight tho

the pc psu idea is good as long as you wire it up right and safely as it can be very dangerous if bodged!
*get one with a pass-thru power socket which will let you power a monitor or external cd-rom!

hope that helps m8
ElectroBlaster is offline  
Old 10 April 2002, 12:08   #7
Bloodwych
Moderator

Bloodwych's Avatar
 
Join Date: Jun 2001
Location: I'm behind you!
Posts: 3,763
Ok guys, if I can't get an A500 65W PSU, what kind of PC PSU can I use. I can buy a 200W Amiga PSU, but they're £50!!!! No-way, I'd rather go the PC route.

Like I've said, I have a spare ATX PSU lying around but how can you mod this to get round the soft-power-on used in PCs? It has no switch!

If no one knows how to mod an ATX, I can pick up AT PSUs dirt cheap off ebay. These of course have switches , but any advice on modding the wiring would be greatly appreciated.
Bloodwych is offline  
Old 10 April 2002, 13:52   #8
RetroMan
Registered User
RetroMan's Avatar
 
Join Date: Aug 2001
Location: Germany
Age: 48
Posts: 3,704
Get an A500 PSU ! I have my A1200 powered with one with these specs : A1200 with Blizzard 1230/50Mhz., 42MB Ram, 2.1 Gig Seagate HD, 40x CDRom and 10MBit PCMCIA Network Card ! No Problems at all
RetroMan is offline  
Old 10 April 2002, 14:35   #9
Bloodwych
Moderator

Bloodwych's Avatar
 
Join Date: Jun 2001
Location: I'm behind you!
Posts: 3,763
Are all the heavy A500 PSUs ok Retro?

Take a look at these:

Power supply choice
Bloodwych is offline  
Old 10 April 2002, 14:45   #10
RetroMan
Registered User
RetroMan's Avatar
 
Join Date: Aug 2001
Location: Germany
Age: 48
Posts: 3,704
Not quite sure but I think so .... The only difference I know is, the light version on A500 got 2,5A and the heavy one 4,5A which will be enough ...
RetroMan is offline  
Old 10 April 2002, 15:35   #11
Bloodwych
Moderator

Bloodwych's Avatar
 
Join Date: Jun 2001
Location: I'm behind you!
Posts: 3,763
I've just found a Goliath PSU for £26 inc P&P.

Please tell me these only came in the 200W variety!!!

If so I'm off to buy!!!
Bloodwych is offline  
Old 10 April 2002, 20:22   #12
jmmijo
Junior Member
jmmijo's Avatar
 
Join Date: Jan 2002
Location: PDX
Age: 59
Posts: 2,380
Exclamation ATX Power Supply Mod

Here's a pdf file on the ATX specs, please refer to section 3.3.2 for the PS_ON# pin on the main power supply connector. There is also a section on the main mobo connector and what each pin does. The main thing is to tie this pin to ground, either clip the wire and connect it to a ground wire or use a switch connected to a ground wire. Section 4.5 has the electrical pinouts!

http://www.formfactors.org/developer...12V_PS_1_1.pdf
jmmijo is offline  
Old 10 April 2002, 22:00   #13
Bloodwych
Moderator

Bloodwych's Avatar
 
Join Date: Jun 2001
Location: I'm behind you!
Posts: 3,763
Thanks jmmijo for the specs and everyone else!

I think I've got more than enough solutions to my power problems now!!!

Once again EAB does the biz, YEAH!
Bloodwych is offline  
Old 10 April 2002, 22:57   #14
ElectroBlaster
Junior Member
ElectroBlaster's Avatar
 
Join Date: Mar 2002
Location: Exeter, Devon, UK
Age: 47
Posts: 1,594
Send a message via ICQ to ElectroBlaster
S'ok m8!

)
ElectroBlaster is offline  
Old 15 April 2002, 16:02   #15
Bloodwych
Moderator

Bloodwych's Avatar
 
Join Date: Jun 2001
Location: I'm behind you!
Posts: 3,763
Why isn't life simple?

I bought a Goliath 200W PSU, which I found is basically a converted PC AT PSU in a nice box.

Since I managed to get it dirt cheap (£18) it's quite cool, as if it blows I can simply replace it with another AT PSU.

Only problem is the darn thing has a circular power connector for the Amiga with 4 prongs .

My A1200 has a square connector. WTF????? Did continental amigas have different power connectors???? Is this a CD32 power connector? It was advertised as being for the Amiga 1200.

I can easily strip down the connector off my 25W Amiga PSU and connect the wires, but I don't want to destroy a perfectly good supply just for a connector. What can I do????????

EDIT: Confirmed, the bloody thing has a CD32 power connector.

Last edited by Bloodwych; 15 April 2002 at 16:39.
Bloodwych is offline  
Old 15 April 2002, 20:08   #16
ElectroBlaster
Junior Member
ElectroBlaster's Avatar
 
Join Date: Mar 2002
Location: Exeter, Devon, UK
Age: 47
Posts: 1,594
Send a message via ICQ to ElectroBlaster
m8 i have the wiring schematic for the a1200's power lead to AT psu!

you will need one of those multimeter testing thingy's to confirm every wire is correct... then you can wire the lead into the psu just like the cd32 one has been (not sure with the goliath?)
i had one years ago

if you want it PM me and i will scan it, might even post the piccy to the zone if anyone else needs it!

J
ElectroBlaster is offline  
Old 15 April 2002, 21:36   #17
ElectroBlaster
Junior Member
ElectroBlaster's Avatar
 
Join Date: Mar 2002
Location: Exeter, Devon, UK
Age: 47
Posts: 1,594
Send a message via ICQ to ElectroBlaster
The info you need is up in the Zone m8
ElectroBlaster is offline  
Old 16 April 2002, 12:57   #18
Bloodwych
Moderator

Bloodwych's Avatar
 
Join Date: Jun 2001
Location: I'm behind you!
Posts: 3,763
I thank you sir, most splendid!
Bloodwych is offline  
 


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
Amiga 1200 clone "Access" on sale! Korodny Amiga scene 31 19 August 2018 05:08
WB technical question... nikvest support.Apps 6 16 April 2008 09:13
technical question about amigas gimbal Nostalgia & memories 1 09 November 2007 14:36
HOL / PHP technical question terryhan HOL suggestions and feedback 3 06 July 2007 12:08
Technical question about C64 Shatterhand Retrogaming General Discussion 19 13 October 2001 14:06

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +2. The time now is 13:03.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Page generated in 0.10296 seconds with 13 queries