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Re: Portadisc

Subject: Re: Portadisc
From: Walter Knapp <>
Date: Fri, 10 Oct 2003 16:48:42 -0400
Jeremy Minns wrote:

>>>It's strange that the software seems rather unpredictable.
>>
>>Like all software, it's very predictable, just does exactly what the
>>programmer wrote. Which may not be what you think he should have written.
> 
> 
> Maybe the Portadisc software is predictable but it's execution is not, on 
> my machine at any rate. To wrap round from TRK001 to the last track 
> recorded, the number of times I need to press AMS<< is variable so I cannot 
> do this without looking at the display - a nuisance in the field. Also, 
> when playing back, the recorded time for a track is not always correct; in 
> this case I have to move forward a track in play and then back again to get 
> the right time. Sometimes even this does not work and I have to press stop 
> and then find the track all over again. Finally, while entering recordings 
> into my data base last week, I noted the correct recorded date and time for 
> a track (08:10 on 19/09/03) and then moved on to the next track. The date 
> and time shown in play pause for this track were quite wrong (05:14 on 
> 26/09/03). This same incorrect date and time was thereafter shown for all 
> tracks, including the one that was right before. Pressing stop and then 
> play pause again didn't help. Neither did switching the recorder off and 
> on. Neither did initializing the recorder. If I put in a different disc the 
> correct recorded date and time are shown for each track but if I put the 
> first disc back the incorrect date and time are again shown for all tracks.

Mine is always exactly right according to what's shown on the table on 
page 13 of the manual. Do note that table gives what you will find while 
playing, not while paused. During pause it probably can't read the data 
from the disk. Which is most likely why you are finding the data 
strange. I could reproduce what you describe in play pause, but starting 
it playing always refreshed the data to the correct data.

> One other point. In stop mode the time is shown in hh:mm:ss format but in 
> play pause as mm:ss/30. Why '/30'? Probably obvious but I can't think of a 
> reason.

The time shown in stop mode is the current time on the internal clock, 
nothing to do with what's on the disk. It's displayed the same way in 
record and record pause, which makes sense where someone may want to 
syncronize starting recording on a specific second. The time shown in 
play is actually hh:mm/30 and is a 24 hour clock time, at least in my 
Portadisc, and is the time stamp read from the disk. Why the /30? I have 
no clue, it never changes. It's kind of like that's some data that's in 
the disk in that format and they did not truncate it. The manual shows 
it like that too.

> I'm happy to say that I'm delighted with the quality of the Portadisc's 
> recordings, which is the most important thing.

Me too.

> PS After I finished writing the above, the machine did it again! After 
> showing the right date (07 and 08/10/03) and time for 54 successive tracks 
> it is now showing 15:50/30 on 22/09/03 for all tracks on the disc. And 
> nothing I do will make it change.
> 
> PPS Finally, after switching it off and on several times, it has shown the 
> right date and time for a track!!!
> 
> PPS And now it is showing this date and time for all the tracks!!! I give up.

I don't have your Portadisc to look at, but I can only duplicate this 
sort of behavior if I keep it in play pause, and it is fine if I play so 
the disk is rotating. Try reading while the disk is playing so it can 
read the actual data. If you are still having problems while playing 
maybe resetting the clock would help. But I think the problem is trying 
to read a stopped disk. HHb can be faulted for not explaining this in 
the manual. I bet if they blanked that part of the display in play 
pause, or showed the system clock there would be complaints.

Note I'd much rather have the disk not spinning in pause, saves 
batteries. This is a minor inconvenience. In my case no inconvenience as 
I use field cards that are filled out at the time of recording and 
include date and time. I've already got the info. I occasionally may 
verify the data off the readout if I'm checking to make sure I'm on the 
right track. Though track numbers are also on my field cards.

On the button pushes to move between tracks, it's consistent in how many 
button presses it needs. Backing through the tracks does require more 
than moving forward, something I've always found strange. At least mine 
is consistent. And I use that a fair amount, so am very familiar with 
it. I don't need to mess with any of that when recording in the field, 
Set overwrite mode in the system settings to off, and it will always add 
the new track at the end regardless of where you were before, you don't 
have to do that wrap. The advantage of a non-linear system. In practice 
I'm looking at the display at that point, having just adjusted the 
record gain, I'm watching the meter. I don't re-record on a disk, and 
only dump a track that went badly immediately, so the track numbers are 
always consistent with my field cards.

As I said,
Like all software, it's very predictable, just does exactly what the
programmer wrote. Which may not be what you think he should have 
written. Which can make you think it's inconsistent.

Walt




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