Search found 313 matches

by bprosman
Sun Jun 07, 2015 9:15 pm
Forum: hardware
Topic: My Beeb got heat stroke
Replies: 47
Views: 3445

Re: My Beeb got heat stroke

How is you power supply behaving ? Still the correct voltages ?
by bprosman
Sat Jun 06, 2015 1:24 pm
Forum: hardware
Topic: Master possible short-circuit on main-board
Replies: 20
Views: 1979

Re: Master possible short-circuit on main-board

Most older switching power supplies were not able to run without some load on it. If you have swapped the PSU it indeed looks like to have an overload situation (in Dutch we would say the PSU has "hickups"). I'm not familiar with the Master but has it 3 separate voltage circuits like the Model B ? I...
by bprosman
Wed Jun 03, 2015 7:05 pm
Forum: hardware
Topic: How to eject a Canon MDD221
Replies: 4
Views: 1097

Re: How to eject a Canon MDD221

It was indeed the arm connected to the solenoid, this time it looked a bit bend. Straightened it and then it worked.

Thanks for the hint.
by bprosman
Wed Jun 03, 2015 9:45 am
Forum: software: other
Topic: other strange 6502 program / i don't get it
Replies: 7
Views: 1545

Re: other strange 6502 program / i don't get it

One of the biggest (3 letter) computer companies has been asked in the past to donate one of their software products to the community (public domain). Their very short response was "Sorry we can't". Later I spoke on a conference to one of their lead developers and he told me that it had been a serio...
by bprosman
Wed Jun 03, 2015 6:58 am
Forum: hardware
Topic: How to eject a Canon MDD221
Replies: 4
Views: 1097

How to eject a Canon MDD221

Currently I have 2 Canon MDD221 drives connected to my BBC model B. For some reason the "Eject" buttons seem t be locked , I cant press them. Does someone know how to eject a floppy ? Or is the locking unintentional and is there something wrong with the drives ? http://www.esmchina.com/IMAGES/SITE/3...
by bprosman
Tue Jun 02, 2015 9:08 pm
Forum: software & utilities for the pc, mac or unix
Topic: TOP853 Eprom programming 27128 roms
Replies: 9
Views: 3142

Re: TOP853 Eprom programming 27128 roms

What did you do to get it to work ?

Usually when loading a file in the eprom programmer software you can give an offset. That should be $4000 for half a 27256
by bprosman
Tue Jun 02, 2015 8:31 pm
Forum: hardware
Topic: Picked up a BBC model B
Replies: 57
Views: 5357

Re: Picked up a BBC model B

Got it to format :-). Can switch between drives.
But loads of question marks inbetween the tracks formatting. Could of course be caused by floppy's and drives laying in the attick or storage for 20...30 years.
Just not able to eject my floppies yet :oops:
by bprosman
Tue Jun 02, 2015 7:55 pm
Forum: hardware
Topic: Picked up a BBC model B
Replies: 57
Views: 5357

Re: Picked up a BBC model B

Today I installed a 8271 and the rest of the chips (sometimes its nice to have "Alzheimer light" :wink: ) , makes you find chips you didn't know you had. Installed Watford DFS I got from Paul. Drives react when I do a *CAT. When I put a floppy in drive light goes on and starts to read, but gives me ...
by bprosman
Mon Jun 01, 2015 9:28 pm
Forum: hardware
Topic: Picked up a BBC model B
Replies: 57
Views: 5357

Re: Picked up a BBC model B

PSU Makeover, I was surprised how clean "Adders" PCB was. In my versions ,as mentioned before ,the capacitors left a smelly sticky sirup kind of stuff behind.

Before :
IMG_1664.JPG
After :
IMG_1667.JPG
by bprosman
Mon Jun 01, 2015 4:50 pm
Forum: hardware
Topic: BBC Port Tester
Replies: 4
Views: 752

Re: BBC Port Tester

//little sidestep. Yesterday I digged trough my IC collection and found about 12 6522's. I can just swap them with a working one in the Atom or BBC but that will not test all functionality.
Thinking about making a port tester just for the 6522.
by bprosman
Mon Jun 01, 2015 2:25 pm
Forum: past events & exhibitions
Topic: Dutch TechSat on 6th of June.
Replies: 39
Views: 5865

Re: Dutch TechSat on 6th of June.

Hi Roland,

Unfortunately due to personal (family) circumstances I cant make it at such a short notice. I would like to be there next year though hopefully with my finished "Roland Atom MKII".

Kind regards, Bram
by bprosman
Mon Jun 01, 2015 8:09 am
Forum: general
Topic: Today I received.....
Replies: 5410
Views: 418247

Re: Today I received.....

Good to hear its fixed :-)
by bprosman
Sun May 31, 2015 10:06 pm
Forum: hardware
Topic: Picked up a BBC model B
Replies: 57
Views: 5357

Re: Picked up a BBC model B

Thanks to Paul (DutchAcorn) who brought me some new C's I repaired 2 PSU's today. I have to say , these go down more spectaculair than I am used to from the Senseo coffee machine where they just die and don't explode. In my PSU's they left some sticky , more like honey/sirup kind of mess on the PCB ...
by bprosman
Tue May 26, 2015 8:50 pm
Forum: hardware
Topic: Picked up a BBC model B
Replies: 57
Views: 5357

Re: Picked up a BBC model B

and the smoke was a sweet kind of a smell.
Was it a Dutch PSU smuggled trough customs ? :wink: :wink:
by bprosman
Tue May 26, 2015 8:41 pm
Forum: hardware
Topic: Picked up a BBC model B
Replies: 57
Views: 5357

Re: Picked up a BBC model B

Coming Sunday I will receive some spare parts, can show how it is done (repair). If it is really (just) the X2 capacitor I would take it out and you should be safe until you have it repaired. as far as I am aware the PSU is safe for a time without but there are people here that are more specialized ...
by bprosman
Tue May 26, 2015 6:59 pm
Forum: acorn atom and system
Topic: Designing a new Atom main board
Replies: 668
Views: 53767

Re: Designing a new Atom main board

Are all pins of the Godil used or can handschake be added ?
by bprosman
Sun May 24, 2015 4:45 pm
Forum: introduce yourself
Topic: Hello from Seattle!
Replies: 11
Views: 1415

Re: Hello from Seattle!

Welcome here. You must be probably the only "Home computer" in the Seattle area not using Windows being so close to Redmond. :wink:
by bprosman
Sat May 23, 2015 8:12 pm
Forum: hardware
Topic: Picked up a BBC model B
Replies: 57
Views: 5357

Re: Picked up a BBC model B

Good idea, I might go for one of Retroclinic's or Beebmasters kits.
by bprosman
Sat May 23, 2015 7:33 pm
Forum: hardware
Topic: Picked up a BBC model B
Replies: 57
Views: 5357

Re: Picked up a BBC model B

BBC's without disc interface but with Econet, perfect candidates for UPURS or Turbo MMC They indeed don't have a disk interface :-(. Will have a look for UPURS or MMC , maybe I try my luck on getting a 8271 from e-bay or something. On the other hand, I paid way less than where they were advertised ...
by bprosman
Sat May 23, 2015 3:03 pm
Forum: hardware
Topic: Picked up a BBC model B
Replies: 57
Views: 5357

Re: Picked up a BBC model B

Next problem is to find a composite (RCA) video capable monitor. Lots of VGA and HDMI screens in the house. Only thing I can try is switch them on and hear they give a low and then high beep and seeing caps- and shiftlock working :roll: :roll: Thanks to my neighbor who had a BNC to RCA connector cou...
by bprosman
Sat May 23, 2015 1:23 pm
Forum: hardware
Topic: Picked up a BBC model B
Replies: 57
Views: 5357

Re: Picked up a BBC model B

it might've been in a school in a previous life.
You won the bonus :D
by bprosman
Sat May 23, 2015 12:45 pm
Forum: hardware
Topic: Picked up a BBC model B
Replies: 57
Views: 5357

Picked up a BBC model B

Today I picked up a lot of 5 BBC Model B's very cheap. As I have never owned one (Acorn Atom was my real "Love") I was wondering where the "Hole" is for on the left side of the keyboard (see attached pic.) Further I understood there is a "Timebomb" capacitor in the PSU ? Or did I misunderstand this ...
by bprosman
Tue May 19, 2015 7:35 pm
Forum: general
Topic: Today I received.....
Replies: 5410
Views: 418247

Re: Today I received.....

BTW ... the second one is only on the picture because I programmed it today
The right one has been assembled upside down :P :P
by bprosman
Mon May 18, 2015 1:56 pm
Forum: other vintage computer hardware, software and games
Topic: Philips P2000C terminal board fault
Replies: 416
Views: 21344

Re: Philips P2000C terminal board fault

//Little offtopic
@Jonb,

Actually curious what el-cheapo desoldering station you have ordered and how it works for you.

Kind regards, Bram
by bprosman
Mon May 18, 2015 12:09 pm
Forum: off-topic
Topic: Desoldering gun - anyone got one?
Replies: 49
Views: 4865

Re: Desoldering gun - anyone got one?

@Alminster,

Done with the Marlin desoldering gun ?

Kind regards, Bram
by bprosman
Sun May 10, 2015 1:06 pm
Forum: acorn atom and system
Topic: Acorn Atom 6502 tracer
Replies: 18
Views: 2703

Re: Acorn Atom 6502 tracer

Some more on single stepping/cycling here :

http://wilsonminesco.com/6502primer/ClkGen.html
by bprosman
Sat May 09, 2015 7:50 am
Forum: acorn atom and system
Topic: Acorn Atom 6502 tracer
Replies: 18
Views: 2703

Re: Acorn Atom 6502 tracer

Hi Dave, What I understand from the Dutch article is that you select an address, that goes into a comparator and the moment you have a "hit" (address detected)it "freezes" the processor by means of "stopping" the clock in a certain state (Fi-0 = Phi0 by the way) . This state has to be a defined one ...
by bprosman
Fri May 08, 2015 7:57 am
Forum: acorn atom and system
Topic: Acorn Atom 6502 tracer
Replies: 18
Views: 2703

Re: Acorn Atom 6502 tracer

Hi Dave,

There is more to it, it also has an address detection circuit, its a whole article explaining it unfortunately in Dutch :
http://www.acornatom.nl/atom_nieuws/199 ... 903006.htm

I'm going through it now, hope I can answer your questions later.

Kind regards, Bram
by bprosman
Fri May 08, 2015 7:34 am
Forum: acorn atom and system
Topic: Acorn Atom 6502 tracer
Replies: 18
Views: 2703

Re: Acorn Atom 6502 tracer

Thanks Wim :-)
by bprosman
Thu May 07, 2015 10:09 pm
Forum: acorn atom and system
Topic: Acorn Atom 6502 tracer
Replies: 18
Views: 2703

Re: Acorn Atom 6502 tracer

Hi Roland,

That would be great !!!
Thanks, and yes I will read all articles.
And it might be obvious I only need (would like to have) a HiRes scan of the working version :wink:

Kind regards, Bram