Interesting things first:  some of the parts arrived. I am still waiting for the boards. I will upload pictures as soon as I have all the ingredients together.

---

Some years ago in one cold winter morning I woke up with a strange idea: measure the width of the tape inside a VHS Cassette. As I found out it was 12.7 mm, exactly as 9-track tape. Some e-mails followed and finally I got around 5 kilometers of VHS tape in refill pancakes from some factory in Netherlands which no longer exists today.

Tape refill was performed in a Fallout-4-style environment:

In the next "VHS - 9 Track Tape Density Experiments (2)" log I will show the detailed test results with pictures and screenshots. I am still running the tests

In the mean time here is the short version: 

 VHS tape supports 6250BPI density only when block size <=16Bytes. As soon as I increase the block size, I get repeated uncorrectable hardware write errors, IHER line goes low and the drive gets unfrozen only when ILOL or IREW are fired.  So my experiment is working only for 1600BPI and 3200BPI.