HP88780A/B

[CA1035749]

How can one tell what interface is used on the HP 88780A/B tape drive? Is it possible to open it up to see which one? Also, is it possible to test he interface without plugging it in (to see which interface and to see if it is working properly)? I had this device working at the beginning of the year. With the SCSI card being changed out and the cable misplaced it is difficult to now know what goes with what.

Thanks!

[BR713004]

Hello Scott,

the 88780A/B was available with three different interface single ended and differential SCSI and pertec-compatible.

The interface might be identified by checking the information logs 24, which will tell you SCSI, HPIB or Pertec.
The different SCSI version might be identified thru the board part number
88780-6xx15 and 88780-6xx35 single ended
88780-6xx16 and 88780-6xx36 differential

x could stand for everything, just version related.

To test the device you might run test 60, which is the interface loopback test, but I do not now if it works without the loopback connector. For more information about testing you would need to check the Service Manual, which might be still available (partnumber 07980-90030). There is no electronic copy of that manual available, because this is a pretty old manual in times before pdf was used for this.

Hope it helps, but a lot of effort to store 200Mb on a tape.
Ralf

[CA1035749]

I looked at the cards that are installed on the right side of the drive and found the following part numbers:
07980-66561
07980-66503
07980-66534

The drive is needed to get data off tapes that I have and not really for storing.

[CA1035749]

Is the loopback adapter, P/N 88780-60096 still available? Or is there a diagram available that shows how the terminator is constructed?

[BR713004]

Hello Scott,

the loopback connector is still available and cost about 55$. It is a differential connector, so it looks like you know now what kind of SCSI bus you have. I was checking some information and the SCSI interface in the back should have 2 external connectors for differential. The single ended version has 2 external connector and plas a ribbon cable connector. You might also check the partnumbers on that board with the numbers I gave you before.

The other partnumbers for the boards you gave me are generic and should be working for both models, so does not help to identify the SCSI version or at least I have no information about it. This tape drive was released first around 1987 and the latest version I think was going out of support last year, but there should be still parts for it available. This tape drive was sold for a long, long time and was going thru a lot of changes, so it might be that the partnumbers are not found, but in a case of problems the latest version would be working.

Ralf