Very Computer

I am trying to read a tape [3490] created on an IBM OS/VS 370 in EBCDIC
using block size 7735 and record length 595.  When I use the following dd
command:

        dd if=/dev/rmt2 of=ascii.data conv=ascii ibs=7735 cbs=595

everything works fine until it encounters nulls (0x00) in the data
stream. When these occur, they are always at position 390 for a lngth of
20.  When the nulls are encountered, dd skips the remainder of the current
record and concatenates the following record, beginning in position 390
for a total of 990 bytes.

If I first read the data from tape to disk without the conversion:

        dd if=/dev/rmt2 of=data.ebcdic ibs=7735

and then convert using a second dd command:

        dd if=data.ebcdic of=data.ascii conv=ascii cbs=595

it works fine, handling the nulls as other data.

Has anyone observed this [peculiar] behavior and do you have a better way
of handling it?

Thank you,
Lucky

Lucky Leavell