Sold A1000 / A1500 / A2000 / A3000 / A4000 ATX to Amiga PSU adapter designed by Ian Stedman

DjCook

8 Bit Dreams
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This project is abandoned - I'm unable to find proper connectors to build these Adapters.... Sorry 🤷🏻‍♂️
Hi!
have built these adapters for me, also offer some here for our Amiga users since this Year A4000 model
became a new life (Acill and hese projects) - these PCB's will need also new power supplie's -
Here comes this handy plug'n'play solution designed by Ian Stedman


2018-09-30 18.50.58.jpg Bigbox_2016-small.jpg DIP-Switch_settings.jpg 2018-09-30 18.55.55.jpg

This ATX to AMIGA PSU adapter allows to use a regular ATX power supplies in our beloved Amigas
Suitable for installation into an ATX tower case or inside an A1000, A1500, A2000, A3000, Amigas4000,
For the A3000, the FAIL signal is available to use.


both voltages are supported: 110V & 230V
generates proper TICK signal 50/60Hz
and provides the -5V.
This is the highest rated power adapter available, it can safely handle the following power levels:

+5V @ 15A
+12V @ 8A

- 5V @ 0.5A
-12V @ 0.5A
This yields a system power of 175W - capable of powering a fully expanded PPC Amiga!

No modifications required to the ATX PSU!
Works with either latching (clickable) or momentary push button switches..


One DIP switch sets the power switch type, momentary (as used on ATX cases) or latching (as used on original power cases.
The other DIP switch sets the 'Tick' frequency.
PCB dimensions are 68x41mm

Asking 15€ for ready built adapter
Shipping anywhere in the world for 7,00€ (4.99€ in Germany)
will combine with other products to save postage fees, so please ask!

IMPORTANT!
Info added by our user
tbtorro :
_FAIL signal is also mandatory for A4000 not only for A3000,
else looks like RAMSEY will not init properly thinking 1MB SIMMs are installed!!!




Also may be ordered with necessary cables - will compare shipping to save postage fees
2018-09-30 18.54.19.jpg 2018-09-30 18.52.34.jpg 2018-09-30 18.55.12.jpg

Asking 15€ for 1x cable Sorry - A3000 is currently NOT available!
Shipping anywhere in the world for 7,00€ (4.99€ in Germany)

will combine with other products to save postage fees, so please ask!

thanks for watching,

-Your 8 Bit Dreams


Received:
timtheloon - 1x Adapter - Parcel delivered
jc_denton - 1x Adapter + 1x A4000 lead - Parcel delivered
tbtorro - 2x Adapter - Parcel delivered
highpuff - 1x Adapter + 1x A4000T lead - Parcel delivered
dib0079 - 1x A2000 with extra cable, 1x A4000 cable - Parcel delivered
RetroPanic - 2x adapter + A2000 cable + A4000 cable - Parcel delivered
caseybarker - 1x adapter + A2000 cable - Parcel deliverd
roc - 1x A1000 with extra cable, 1x A2000 with extra cable - Parcel delivered
Nowee - 1x adapter - Parcel delivered
izi - 1x adapter - Parcel delivered
timtheloon - 1x adapter - Parcel delivered
fabbie54 -1x adapter + A2000 cable Parcel delivered
marchigianluca - 1x adapter + A1000 cable - Parcel delivered


interested
Persons :
multivac - 3x adapter + 3x A4000 cables
o0Nosferatu0o - 1x adapter
Dunerazor -1x adapter + A4000 cable
Animoid- 1x adapter + A1000 cable
Andry- 1x adapter + A4000 cable
doop_snoop - A2000 cable
bfarmilo- 1x adapter + A4000 cable
leof- 1x adapter + A4000 cable
Joxe - 1x adapter + A2000 cable
Free_Jack -1x adapter
Lord -1x adapter

screemo - 1x A2000 with extra cable, 1x A4000 with extra cable - Payment info sent
signman - 1x adapter + A1000 cable - Payment info sent
bobymiller - 4x adaptrs with A1000 cables, 2x adapters with A4000 cables

 
Last edited:
So how is this board generating the tick signal? Some 555 timer solution? It is obviously not converting the mains AC to a tick signal like the original PSU. Was just wondering about the precision of this tick signal since the mains tick signal is supposed to be quite accurate (averaged over a day), but of course then you can't get a 50 Hz tick if you are in 60 Hz countries..
 
Glad, You've asked, Martin, let me explain how it works:
There is a small PIC controller on the board, this chip is responsible for two tasks: switch You plan to use (mechanical or button type) and frequency for tick signal. Tere are also two switches to change these settings. I took two pictures with my scope, so You can see how precise TICK signal is:
2018-10-04 22.42.35.jpg 2018-10-04 22.43.21.jpg
As You can see - 50Hz is absolutely perfect, this means You can live in USA, for examle, use 110v ATX psu, yet run perfectly a PAL system,
and vice versa: here in Europe You can take a standard ATX PSU and get 60Hz out of it thru this adapter to run a NTSC Amiga..
I think it's really great, isn't it!?
Regards,

Viktor
 
Last edited:
There is a small PIC controller on the board

Ok, so the accuracy comes down to how this PIC is clocked. I know that it is just a minor thing but if the frequency is off by say 100 ppm then the clock would also be running faster / slower by that same amount when the system is on. A quartz-crystal clock is usually accurate to around 6 ppm and then RTCs have additional compensation circuits to improve that accuracy even further. An internally clocked PIC will not be very accurate in this regard.

The benefit of using a true mains frequency is that (in 50 Hz countries) they take care to hit exactly 50*60*60*24 cycles per day. While it may be a tad slower during peak hours, they speed up to compensate during the off hours. That way, they ensure that clocks (most typical alarm clocks for example) is running accurate.
 
Hmm..not sure i understanding Your "if" correctly, have posted some pictures in post #8 these showing percectly clean tick signal, see no reason why this will be different in some way..can You exlpain please?
If this adapter doesn't fit Your needs - i can offer another, designed by Matze, it has oscillators installed:
ATX-Adapterlatine-Beschrieben-K2.jpg
 
Last edited:
Yes, I know that the tick signal is looking clean but I was referring to the frequency accuracy of it. Your scope shows the frequency with up to two digits which corresponds to ~100ppm. A 100ppm inaccuracy would mean the the clock could be off by about 8½ seconds per day. But as I wrote, this is only a minor thing since the system is most likely to be off most of the time, running off the quartz crystal which is quite accurate. Your tick signal is likely better than 100ppm, but I was just wondering about it since I put together a similar circuit myself.
 
I can send You a schematic from Matzes ATX adapter if You interested, maybe You can use it for Your project...
 
Thanks for the offer, but I ended up using a small transformer which converts the 230VAC to 9VAC which is then reduced using some resistors and diodes and then fed through a comparator circuit to generate a clean 0-5V 50% square wave. I know that in practice it isn't really significant whether it is a synthesized tick signal or derived directly from the AC. It is not like anyone today would keep their A2000 running 24/7 and use it as an alarm to wake them up in the morning. Even if they did, if the alarm goes off a few seconds late it is not the end of the world. :)

There is a massive amount of space inside the A2000 PSU case, so I went for the slightly bulkier solution..
 
Payment received from highpuff,
P8/P9 connectors are ordered,
Will update tracking information once parcel is sent
Thanks for supporting my hobby!

Viktor
 
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