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bbcmicro
April 5th, 2007, 08:48 AM
I have had limited success downloading BBC tape image files from the extensive stairwaytohell library and converting them back to audio with FreeUEF, playing thorugh my PC speaker into which is plugged one of those mp3 to tape things (Y'know, those tapes with the jack on them) and that is itself inside a cassette player connected to my beeb.

I say limited success, because of the 10+ files I have tried only Snapper version 1 and 2 (1 being a near exact copy of Pac Man) and Sentinel (Different to The Sentinel) work. Others dont load at all, give errors or get stuck at the loading screen.

Can anyone point me towards some Tape Images that are less flakey/more tolerant of this somewhat long winded set up? not necessarily from a different archive, but ones which definately work.

I presume that the conversion of original tape to tape image preserves flaws in the original tape when converted back?

Thanks.

nige the hippy
April 5th, 2007, 10:02 AM
You tend to lose a bit of treble when using one of those tape adapters which will affect pulse edge position badly, and also volume can be variable depending on how the adapter is put into the player and volume tends to be critical (as you know). Have you considered going straight into the beeb with the PC line output? make a note of the volume control settings on the PC when it works best. it might help remove a few "variable" variables.

bbcmicro
April 5th, 2007, 11:07 AM
Thanks Nig, there's certainly something going wrong.

I used an emulator to check if it was the image or the tape's fault. The majority that wouldn't load on the beeb wouldn't load on the emulator (And yes, I did try *RUN for binary files) but a few did. At least I now have the Pugwash Theme on 5.25" disc!

dongfeng
April 5th, 2007, 11:29 AM
Is there any way to write straight to a BBC-formatted 5.25" floppy disk on a PC? That would be very useful, considering most of my BBC software has suffered from bit-rot. Thankfully the master disk still survives!

Even so, I would be very interested to hear about your file-to-tape conversions :)

bbcmicro
April 5th, 2007, 12:01 PM
I think there is, but I haven't got the right media to try. I have really poor luck with 5.25 drives, I can never seem to get them functioing properly. There used to be a site called 8bs.com about a year ago, full of all interesting beeb stuff. Alas, 'tis no more. I seem to remember soomething called Omnidisk or Omniflop being able to write BBC images. It can be done, anyway. There is also Xfer (Or something like that) which needs software on the PC and Beeb, and a calbe but data can be sent directly from one to the other. It's all a bit hazy.

bbcmicro
April 5th, 2007, 12:10 PM
Ignore this if you like, it's just a bit nagging. I am probably completely wrong but it's guesswork anyway.

OT, I'm having trouble copying binary files from Emulated disk to Emulated tape. I suppose it would be identical to real life anyhoo.

I've been trying something like

*DISC
*INFO "nnnn"
>xxxxx xxxxx xxxxx xxxxx (lotsa numbers here)
*LOAD "nnnn"
*TAPE

About here I get lost. All the above is a guess so most definately wrong.

I know I have to do something with the execution address and the like to save with the *SAVE xxxx xxxx (More numbers) command But I can't remember what!

I use WE DDFS 1.53

bbcmicro
April 5th, 2007, 01:37 PM
After much volume tweaking, my success rate is about 50% for programs greater than 4 minutes long, and near enough 100% for smaller ones. Now I just need to get them on tape, as almost all of the images are copy protected somehow, as I want tape copies. I though of two ways to do this without constructing a cable (Probably simpler anyway, but where's the satisfaction?)

Get a 2 tape deck, use the mp3 tape thing and a computer to copy directly to another tape.

Problems:
My success rate may decrease even more
Only my brother has a dual tape deck, and not a PC nearby.

I could convert the .UEF to .WAV files, burn them onto a CD-ROM and record them to tape on a CD/tape deck

Problems:
Perhaps the digitisation will decrease the quality even more? Maybe not, they have already been converted from a file, and I would have thought the beeb would prefer near straight 1s and 0s instead of the original analougue recording. I don't know, i'm thinking out loud here.

Second problem, I've tried this before a few years ago and it didn't work. Perhaps a different (newer) deck, different results?

I'll have to wait till tomorrow to test out my theory.

Thanks for listening to my witter.

nige the hippy
April 6th, 2007, 02:17 AM
Probably a good idea to write from the sound out of the PC to a good tape deck, using an ordinary crappy domestic tape deck is not good, as they usually have an automatic adjustment for the record volume, which means that after every gap in the data stream, the record volume goes up to compensate for the silence, resulting in bad distortion for a fraction of a second. If you get / borrow a tape deck with a manual volume control, and manually set the level on the meters to 0dB during the data screams (you'll see when you are doing it), use fairly good tape (something like CrO2), AAH! and make sure you're recording in mono, you will have as good a recording as possible.

It'd be interesting looking at a data screech in something like sound forge, I wonder if there are any tools to clean-up and re-generate tape images? I doubt it, as it's so esoteric.

loading from tape was always a bit hit and miss on home micros.

bbcmicro
April 6th, 2007, 03:04 AM
hmmm...The only tape deck in the house (Except for Joe's) is an old Phillips one from the early 80's with a 5 pin DIN for all audio in/out. It's this I've been using. Its old, so it's not great quality. Joe's is part of a unit, so I can't lug it to my PC. I spose I'll have to keep my eyes peeled, in the mean time I'll do the best I can with what I've got. I spyed a 5 pin DIN to 2 mono jack lead on Maplin.

I have used Audacity in the past to filter out noise on some tape recordings (not images), but it distorts quite heavily.

I need to buy some new tapes too.

carlsson
April 6th, 2007, 07:00 AM
One Omni-program is for DOS and older Windows. The other Omni-program is for Windows 2000/XP. I can't recall which is which, but it is self explanatory once you have researched the subject. When it comes to 5.25" drives, it seems to matter which brand your 5.25" PC floppy/controller is, how well it will be able to write floppies.

I have a similar problem with 3.5" floppies to my BBC Master Compact. My previous AthlonXP 2000+ w/ Windows 98SE was not fully able to successfully write floppy images, but when I tried a Pentium-II with XP, it worked fine. My current AMD64 computer doesn't even have a floppy controller, and USB floppy drives are a total No-Go when it comes to these matters. I've brought up my old Pentium 200MMX which I'm planning to try to use to write floppy images, hoping that its on-board floppy controller is more functional than the ECS Athlon board. As a matter of fact, I connected the floppy drive to the Pentium II, to verify that the drive itself is compliant.

Update: OmniDisk is the old version, OmniFlop is the newer one. I successfully managed to format an ADFS floppy on my old PC, and am expecting to be able to write images too, the day I feel a need for that.

bbcmicro
April 7th, 2007, 02:57 PM
mmm....Master Compact.

Certainly not Olivetti's best choice business wise, but they definately look good!

I have appaling luck with 5.25 disks, maybe I should invest in new media? I've been using regularly 1 5.25" disk with 30+ typed out programs on from the last 2 years. I suddenly wise up and think; "Hmm, I should make backups" Arg! Bad sectors! Halfway through copying file by file, no fun with a single disk drive :( I might have RSS from disk swapping!

All self inflicted, when will I learn?

I tried a new method today, First convert the .UEF tape images to .WAV, then copy to my brothers iPod (No conversion required), then play through the cassette adapter on a dual tape deck whilst recording to another. So far I have 100% success, with Arcadians, Chuckie Egg, Meteors and Snapper. Snapper is one of the best Pac-Man ports I've played, to the point of legal action from Namco.

Right now I'm making a copy of Fortress, my personal favourite. I hope it works!

Terry Yager
April 7th, 2007, 03:05 PM
Tell me about it! I've just spent the better part of an afternoon preserving the still-usable files from my K10. Time-consuming, but prolly a necessary evil.

--T

bbcmicro
April 7th, 2007, 03:09 PM
Ah, you would have thought I would have learned a year ago, when I lost 40+ pages of GCSE geography coursework and 2 GCSE English Literature and Language essays! Of course, by the time I would have had enough money to buy a new motherboard, the deadline would have passed, so I stayed behind for an hour and a half every night at school for 3 weeks, handed it in and got an A, compared to a C for my original drafts. So, this story has a strange moral. Don't back up, your grades will improve!

It's funny, I work best in a panic. And I never did bother to repair that PC. I should really.

Got Fortress in my Beeb and is loading while I speak.

Fingers crossed!

Terry Yager
April 7th, 2007, 03:10 PM
I tried a new method today, First convert the .UEF tape images to .WAV, then copy to my brothers iPod (No conversion required), then play through the cassette adapter on a dual tape deck whilst recording to another. So far I have 100% success, <snip>

So, I've been wondering myself...the stereo/mono issue doesn't make any difference? I mean, copying from a mono tape to a stereo system, then reversing the process (back to mono again) is not ConsideredHarmful?

--T

bbcmicro
April 7th, 2007, 03:15 PM
It doesn't seem so...I mean, it's a mono tape, converted to a mono file, so when played back it's still in mono and recorded to a mono tape. I don't think it ever gets converted to stereo. Not sure, really.

Blah! Fortress didn't load. It was the worst type too, the loading screen comes up and it beeps on boops with the software house logo, and you think it's working. Then it loads completely and....nothing happens. :(

Mind you, it isn't necessarily the process, a lot of images I've found are bad and won't load in an emulator either, with the exact same symptoms as the actual beeb I tried to load them on.

Terry Yager
April 7th, 2007, 03:23 PM
I'm just thinking that copying to the sound card is different from copying directly from tape to tape. Might it automatically convert to a stereo file? If it's working for you though, that's reassuring.

--T

bbcmicro
April 7th, 2007, 03:26 PM
I dunno, if it converted it into a stereo file, how would it do that? I mean, how would it split the audio automatically without knowing what you wanted? except from 50/50 to L and R. In effect, that could halve the volume of the final recording I s'pose

maybe such software channel tomfoolery is achieved by seperating treble and bass and the like?

I should look into it before posting such open ended questions! Sorry, force of habit.

Terry Yager
April 7th, 2007, 03:37 PM
No prob here, I'm just interested because you're doing something that I've wanted to do myself. I finally tried a couple weeks ago, but I'm still waiting to hear back from the person I emailed the (mp3) sound files to, so I still don't know if it works or not. I actually made images of a couple of commercial HX-20 software tapes, and sent the files out, but whether they can be written true to another tape, then loaded into the computer is still up in the air for me.

--T

Terry Yager
April 7th, 2007, 03:49 PM
Another thing I'm wondering is whether the patch cord makes any difference? I used a stereo cord for reading the tapes, but I don't know if a mono cord would make any difference or not.

--T

nige the hippy
April 8th, 2007, 03:51 AM
The business of recording in mono etc goes like this....

you get a sharper copy of a mono tape by recording using one stereo channel, than by mixing the left and right channel signals...

Technical reason being that any azimuth error of the head will give rise to a slight time difference between the outputs. As the frequency rises, that translates to a bigger and bigger phase difference,

... and a loss of high frequency signals when you add them together.