Encoding of BASIC source code on punched tape

I recently bought a few punched paper tapes from an eBay seller. They were said to have been from an IMSAI system, and I found BASIC source code on them. Except for the leaders at both ends consisting of NULs, the rest of the bytes on each tape have the most significant bit set. As I understand it, Teletype model 33 ASR units are conventionally configured with MARK parity keyboards when used with PDP-8 systems, and I gather that it's conventional to encode PDP-8 source code tapes with MARK parity. I'm guessing that the same convention was used on the IMSAI, or at least was used by the original creator of these tapes. I just received a GNT model 4604 tape punch/reader yesterday, and today I got it working after making a few repairs. Then, I set to work reading in these tapes and converting the raw binary images (which I saved separately) to plain ASCII text by clearing the MSBs, and dropping any NUL and DEL characters. One tape included a splice which the creator marked with red ink. Each line was terminated by the sequence CR-LF-DEL-DEL. I presume that the two DELs after each line were there to give a 33 ASR (or similarly slow printer) time to return the carriage before the next line starts printing. Here is my question: Is it conventional and/or important to include the two DELs after each line when creating a source tape which is to be read in to a BASIC interpreter, or is that just an artifact of how the tapes were created (i.e., by printing source code out to a 33 ASR printer)? I ask because I want to know if I should include the DELs if I ever create new tapes from the extracted text files. The tapes were marked with 1976 dates, and were named: STRTRK DIET BLUFF I'll share their contents on my web site soon, and I'll also try running them in a BASIC interpreter sometime. -- Mark J. Blair, NF6X <nf6x at nf6x.net> http://www.nf6x.net/