Can't seem to get a reliable backup to new tape using my C2N

[rossoe]

I was getting good backups with the 1530USB, but having trouble getting any of the backups recorded back to tape.

Azimuth was adjusted using an azimuth program live on C64, and also a 3000Hz calibration tape was used to calibrate motor speed.

I decided to also get a DC2N4-L to see if it helped with added graph analysis/visuals of the back ups and also exploring usage of DMP's as initial backup storage. so the tests below are combo of backing up with DC2N4 and then recording to a C2N with 1530USB & AutioTap.

Test 1: - Using my own copy of super zaxxon copied to DMP via a DC2N4-L
volume at %70
The red arrow was just me noting when it recognised the file name.
Result - This played fine in VICE 3.8






Then I recorded the DMP from above back to tape, by first converted back to TAP, and then backed that up to check the results, it seemed alot more spread out than the read performance from prior test?
This failed to run in VICE, or be recognised in TAPClean




I then switched to backing up to tape a small prg called azimuth, so that I could iterate through the tests quicker:

Test 2: -
volume 100%
Freq 44100
Result - failed to run in VICE & Failed TAPClean







Test 3: - This was the closest I seemed to get to having TAPClean recognise the tap after converting from DMP
volume 75%
Freq 44100
Result - failed to run in VICE & Failed TAPClean





I've tried testing with 96000freq and it does not improve things in this instance.
I don't know if this is an issue with settings, or something not right with my recording part of the head? as the read seems to be ok given I can make good backups of original tapes.

I've attached the 3 TAP files from above failed attempts:
new_super_zaxxon.TAP
azimuth_100_44100.TAP
azimuth_75_44100.TAP

[Remzi]

Try recording this WAV file to cassette tape.

Use VLC media player,volume level %100.
Windows USB speaker volume at %90.

See if it loads fine on real C64.

[rossoe]

Thanks Remzi, I ran that head.wav through VLS at the settings you noted on the 1530USB - here is the visual after backing up in the DC2N4 serial client:




DMP results in TAPClean:




Post a clean operation in TAPClean - which also saved it out to a TAP:




I ran a 2nd backup and got slightly higher Recognized figure of 96%:




Results on real C64 - it came up with some flashy colour bars for a few seconds then back to Ready on Blue screen (same in VICE 3.8 ):




Here is the DMP and TAP generated:
test_WAV_04.DMP
clean.test_WAV_04.tap

Whilst I had the C64 out I also tested out original copy of Crazy Comet and Super Zaxxon which all loaded and worked fine from the C2N.

What is the recommendation re recording over the same tape? as during all these tests, must have been 20-30 tests in a row I used the same 2 tapes, which were fresh and unused initially, but would I see any issues re-recording over the same section of tape that many times?  understandably I'm sure it's best to use fresh tape when making master backups, however I can't really do that for iterative testing like this, as I have limited amount of fresh tapes.

[Remzi]

It's picking up quite a bit noise.You should try a different tape deck.