PXL tapes

["Alexander the Great jr." <kanaris@bode.usc.edu>]

> > Does anyone have any recommendations concerning brand and model cassette 

> > tape to be used with a PXL?

>  

> 	I generally use Maxell XLII-S, though the regular XLII type

> would probably do just as well. The original "PXL Brand" tapes that

> Fisher-Price sold were just repackaged Maxells, though as they were 

> not labelled as such I don't know whether they were XLI or XLII.



The identifying holes on the cassette shell can be checked to find if

the original tapes were Ferric Oxide or Chrome Oxide.



> > Also, another question...  Can anyone tell me why Fisher Price decided to 

> > split the tape into 5 minutes per side, instead of utilizing the whole 

> > tape, thus 5 minutes one way.  This would have greatly increased the 

> > available bandwidth.

> 

> 	Though I don't know for sure, I always assumed that the idea was

> to minimize confusion for the kiddies, so they wouldn't have to remember

> which side was the "recording" side. Also, if tapes can be flipped over

> one doesn't need to spend so much time rewinding.



I do know for sure. The recording format is linear, NOT HELICAL scan. 

A stationary head is being used. So unlike your home VCR which lays 

its tracks diagonally on the tape and can therefore benefit by a wider

tape because it can record longer tracks, your PXL track length is

limited by the length of the tape not the width. If they wanted to 

increase the bandwidth they would have to run the tape faster than

they do. This would further reduce the recording time. 



The bandwidth of a cassette tape at 1+7/8 inches per second is about

16KHz. If the C-60 tape lasts 5 minutes per side, it means they run

the tape six times faster than normal. That is 1+7/8 * 6 = 11.25 ips.

The bandwidth can be expected to be approximately six times higher

as well, so you get 96 KHz on your PXL per track. (I don't know

if they use more than one track) 



If the C-90 tape lasts 5 minutes per side, it means they run the 

tape nine times faster than normal. That is 1+7/8 * 9 = 16.875 ips.

The bandwidth can be expected to be approximately nine times higher

as well, so you get 144 KHz per track. 



I don't have a PXL, so I cannot verify the frequency response estimates.

If someone in the Los Angeles area is willing to lend me his PXL

for 5-10 minutes, I could verify all that. I mean I can verify

while you wait, you don't have to give me your precious camera.

If you can tell me for sure how many tracks they use, (you can find it

by carefully looking at the recording head) it would be helpful as well.





Alex Kanaris