RISC 2500 adapter

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Reinfeld
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Posts: 486
Joined: Thu Feb 17, 2011 3:54 am
Location: Tacoma, WA

RISC 2500 adapter

Post by Reinfeld »

I have the 2 MB version, purchased last year from a European owner. I had to buy a voltage converter to use the original adapter, which appears to be dying.

Background: I was running a little game between RISC 2500 and Mephisto Atlanta. After a tough struggle, RISC 2500 pulled off a lovely endgame maneuver to queen a pawn just ahead of Atlanta, ensuring a pure technical win...and then the adapter got jostled and RISC 2500 conked out. I tried a few simple things, including the ACL button, but it no longer responds to the rather battered adapter, which was shaky to begin with (the converter plugin setup is very awkward.)

I know it's a temperamental machine. Here's my question:

1) Is it possible to purchase a generic US adapter that fits the parameters? If so, what would be required?

I ask because I know this works with other machines, including my Novag models and the recently acquired Berlin Pro. Any help?

2) Failing that, does anyone own a spare US or Euro adapter for this machine, and would they be willing to sell it? I am a generous buyer.

Adaptable regards,

- R.
"You have, let us say, a promising politician, a rising artist that you wish to destroy. Dagger or bomb are archaic and unreliable - but teach him, inoculate him with chess."
– H.G. Wells
Larry
Senior Member
Posts: 2269
Joined: Wed Aug 01, 2007 8:42 am
Location: Gosford, NSW Australia

Re: RISC 2500 adapter

Post by Larry »

Reinfeld wrote:I have the 2 MB version, purchased last year from a European owner. I had to buy a voltage converter to use the original adapter, which appears to be dying.

Background: I was running a little game between RISC 2500 and Mephisto Atlanta. After a tough struggle, RISC 2500 pulled off a lovely endgame maneuver to queen a pawn just ahead of Atlanta, ensuring a pure technical win...and then the adapter got jostled and RISC 2500 conked out. I tried a few simple things, including the ACL button, but it no longer responds to the rather battered adapter, which was shaky to begin with (the converter plugin setup is very awkward.)

I know it's a temperamental machine. Here's my question:

1) Is it possible to purchase a generic US adapter that fits the parameters? If so, what would be required?

I ask because I know this works with other machines, including my Novag models and the recently acquired Berlin Pro. Any help?

2) Failing that, does anyone own a spare US or Euro adapter for this machine, and would they be willing to sell it? I am a generous buyer.

Adaptable regards,

- R.

You say the converter plugin setup is awkward, I can relate to this
since I have the same problem when converting the other way, ie, from
120V to 240volt. Do you have a voltmeter? Your first port of call here
is to get hold of a voltmeter and then satisfy yourself that you are
getting a reading from the adaptor when it's plugged in. I'm hoping
the 240/120 converter is the problem and not the risc2500.
The risc2500 died when the setup was jostled, it only takes a millisecond
power interruption for it to happen. It's frustrating when it happens.
You are right, the risc is a temperamental beast. It's also fussy when
it comes to power input. Reading the back of my original HGN 5050
adaptor, it says "5V-/1A/5VA"
This means 5volts direct current positive tip/ 1 amp / 5 volt-amps
Putting a voltmeter on it (with no load) it reads 5.7 volts. I've got another
adaptor, also HGN5050, that reads (with no load) 6 volts. I'm guessing
there is a tolerance from one adaptor to the next. Either of these adaptors
work with my risc or montreux machines.
Notice I said "with no load". This is because the adaptor is "regulated".
A non regulated adaptor will show quite a higher voltage when it is
not under load. Try your local electronics store. If they don't have one
they can probably get you one. Repeating myself, it is VITAL that the
adaptor be regulated.
I have noticed with my risc2500 machines that when they freeze with
an "ERR TRAP" message, or sometimes even without the message,
pressing the "acl" button to clear the problem does not completely go away.
The idea is to reset the machine, clearing away any static charge.
However by putting the machine away in the closet and getting it back
out the next day the problem has gone away and the machine works
fine again. Of course you know to clear the RAM on power-up.
The risc draws a fair bit of power, that's why they made it so it will
not run on batteries. They would be forever going flat. So when you go
to the electronics store, specify a 1 amp output, and STRICTLY no more
than 6volt output adaptor, even when not under load.
Let us know how things turn out.
Larry
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ricard60
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Location: Puerto Ordaz

Post by ricard60 »

Also be aware of the polarity +/- some voltage converter have a switch to reverse them.
Reinfeld
Member
Posts: 486
Joined: Thu Feb 17, 2011 3:54 am
Location: Tacoma, WA

Post by Reinfeld »

Fortunately, this appears to have been a one-time problem. I left the RISC alone for a few days and fired it up tonight. All systems go. Thanks to all advisors.

- R.
"You have, let us say, a promising politician, a rising artist that you wish to destroy. Dagger or bomb are archaic and unreliable - but teach him, inoculate him with chess."
– H.G. Wells
Larry
Senior Member
Posts: 2269
Joined: Wed Aug 01, 2007 8:42 am
Location: Gosford, NSW Australia

Post by Larry »

Reinfeld wrote:Fortunately, this appears to have been a one-time problem. I left the RISC alone for a few days and fired it up tonight. All systems go. Thanks to all advisors.

- R.
Excellent news!..., remember, the risc is a temperamental beast.
L
paco5560
Member
Posts: 9
Joined: Fri Mar 13, 2015 1:50 pm

have one working

Post by paco5560 »

Must try this adapter Dell PA-14 AC Power Adapter - P2040
It has exact 5.4v and 2Amp demanding from your RISC2500
At this time I think you fried your Risc 2500, bit do not worry, I repair mine, there are a 2 transistor that came bad, hope on your case this transistor wen open, if they are shortcicuited, then there are going more electronics chips damaged even main processor. Hope this is not your case.
I think every one of the chips you can buy today in any electronic store, they are a 2 chips (that needs to be programmed) Gals 16v8 I got them and so the main Eprom.
Any help I can give you, count on it. famher556@sbcglobalnet
This happened because different supply voltages, in Europe is 240vac, in usa 120vac, you can go from there, you gave half of the need for that particular power supply is a matter of time to ruin it and whatever is connected to it.
Ok to much talking. I can help if you want, let me know
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