Search found 97 matches

by mikeb
Tue Sep 17, 2019 5:08 pm
Forum: Technical questions
Topic: Telestrat failure?
Replies: 24
Views: 2192

Re: Telestrat failure?

I usually try isopropanol, methylated spirit, white spirit, paraffin, cellulose thinner (xylene/toluene) or mystery RS "Computer Solvent" in turn until something seems to dissolve :)

I'll add lighter fluid to the list!
by mikeb
Sat Sep 14, 2019 6:02 pm
Forum: Technical questions
Topic: Oric 1 with messy video problem
Replies: 11
Views: 139

Re: Oric 1 with messy video problem

I can see it only if, together with the s-video to scart cable, I'm keeping attached also the RF cable! Just on that point, it sounds like your lead is not connecting the ground connection through correctly, and you are "stealing" a ground connection using the RF/coax lead's shield, from Oric to th...
by mikeb
Sat Sep 14, 2019 5:57 pm
Forum: BASIC programming
Topic: cataloguing tapes
Replies: 16
Views: 240

Re: cataloguing tapes

30 DOKE #2F5,#9700:!" " Nicely done iss . I left out the DOKE-to-activate line bit (this allows "!" to become a user defined command pointing at the new machine code). The line quoted sets up a pointer to the just-loaded machine code, and then immediately executes it. As per the above posts, one wr...
by mikeb
Fri Sep 13, 2019 4:49 pm
Forum: Technical questions
Topic: removing Oric keyboard
Replies: 2
Views: 51

Re: removing Oric keyboard

Unless some contortionist/comedian *has* soldered the things together -- I'm not sure how you would manage it, yes that's the connector, and it really should just pull apart -- there's no catch or screws (other than the three along the top edge of the board). It's just a 14-15 way 0.1" Molex style c...
by mikeb
Fri Sep 13, 2019 4:46 pm
Forum: BASIC programming
Topic: cataloguing tapes
Replies: 16
Views: 240

Re: cataloguing tapes

my brain did an "undefined statement" error every time it was presented with machine code :lol: Do you just type that stuff in as it is printed in the magazine? Or go via an assembler? For most simple stuff like this, unless you have an @iss around to type it up for you :) , you'd cobble together a...
by mikeb
Wed Sep 11, 2019 5:05 pm
Forum: BASIC programming
Topic: cataloguing tapes
Replies: 16
Views: 240

Re: cataloguing tapes

I recall an article in Oric Computing, headlined something like "Has anybody seen my cat?" which had a listing for this ... let me find it... Ah yes, Issue 2, page 4. If you don't have the magazine, click below http://www.defence-force.org/computing/oric/library/lib_magazine/oriccomputing/index.htm ...
by mikeb
Sat Sep 07, 2019 6:19 pm
Forum: Hardware hacks and extensions
Topic: PC-style audio output socket
Replies: 3
Views: 100

Re: PC-style audio output socket

Yes, it's doable, you will miss some of the delights of the speaker being overloaded and driven to distortion though :) As you look into the tape connector (5 pin), the extreme left and right pins are cassette in/out. The centre (top) pin is ground. The two remaining pins directly next to ground are...
by mikeb
Fri Sep 06, 2019 4:41 pm
Forum: General Discussion
Topic: Introducing myself
Replies: 30
Views: 787

Re: Introducing myself

As long as it can fit between the 0.1" spaced pins -- that's a mighty small pen, and, importantly, has a fairly constant sized hole drilled up the middle (not just a little hole at the end that widens out inside!) then that would work too.
by mikeb
Wed Sep 04, 2019 4:38 pm
Forum: General Discussion
Topic: Introducing myself
Replies: 30
Views: 787

Re: Introducing myself

Good news on the pin straightening :) Your rotary whatchamacallit is quite broken. Variable capacitor CV1, it's used to create the colour signal for the UHF output only. You can desolder it and throw it away (and have no colour UHF output) or find a replacement (2.22pF, original is Mullard 808-11229...
by mikeb
Tue Sep 03, 2019 5:08 pm
Forum: General Discussion
Topic: Introducing myself
Replies: 30
Views: 787

Re: Introducing myself

Then you just need to find a metal tube small enough to fit over the pin. A bit of brass tube should do the trick. I linked that tool as an example of what I was talking about, not necessarily a recommendation to buy :) Brass tube is probably no good -- you need something that is stiffer than the t...
by mikeb
Mon Sep 02, 2019 5:19 pm
Forum: General Discussion
Topic: Introducing myself
Replies: 30
Views: 787

Re: Introducing myself

I have tiny jeweller's needle-nosed and flat-nosed pliers too, they'll come in handy. You should get by okay with those. There's a tool that music-box repairers/clock fixers use that is designed for this, for slipping over a pin and levering it straight (a hollow stainless steel tube closely matche...
by mikeb
Sun Sep 01, 2019 5:05 pm
Forum: General Discussion
Topic: Introducing myself
Replies: 30
Views: 787

Re: Introducing myself

Mmmmmm.... I don't remember if the Oric 1 rom performed a memory test. It does -- not an extensive one, but that's why you get a wipe-down of black-white fine bars (looks grey) about 2 secs after bootup, just before the text screen appears, and why unused memory is filled with UUUUU -- the test wri...
by mikeb
Mon Aug 12, 2019 5:16 pm
Forum: Hardware hacks and extensions
Topic: Printer cable: Oric to DB36?
Replies: 10
Views: 1870

Re: Printer cable: Oric to DB36?

I'm not sure if DB36 is the right description -- I think of DB as being the DB-9/15/25 "D-sub" range (like for mice, joystick, serial ports) A proper Centronics was usually an Amphenol 36-way (2 row) connector. Like the IEEE488/GPIB/HPIB (24 pin?) but obviously bigger. See: https://en.wikipedia.org/...
by mikeb
Sat Aug 10, 2019 7:44 pm
Forum: Technical questions
Topic: Oric-1 Repair
Replies: 44
Views: 4119

Re: Oric-1 Repair

I've got an Atmos that boots but it is rather reluctant. It can take 3 or four times plugging in the power supply. I've swapped the C8 and C21 with no change. The chips are mostly socketed so I've swapped 6502, 6522 and RAM and it is still struggling. When it powers up (but fails to boot), what hap...
by mikeb
Tue Jul 23, 2019 5:48 pm
Forum: Technical questions
Topic: A possible software alternative to Vsync?
Replies: 47
Views: 23613

Re: A possible software alternative to Vsync?

Simple. Real PAL television sends a 312 line field followed by a 313 line field (interlacing). Neither 312 nor 313: Split the difference and it'll be fine: For real PAL it's actually 312 and a HALF lines in each field, which is why the second lot of 312.5 land "between" the first set (to interlace)...