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  by Bill Degnan - 07/21/2018 11:07
Juergen writes:
>
> VintageComputer.net Inquiry Contact Information Name: CMGB
> Email: cmuseumgb- at -gmaildot com Comments:
> In regards to blog post titled Rockwell R6500 (AIM 65):
> I am one of the founders of the Computer Museum in Basel (CMBB/CMGB). We have 2 AIM 65 units that seem functional. However, we're experiencing problems with the cassette drive when trying to read back. We tried to record using cassette recorders and also a modern PC through line in and the audio signals are clearly recognizable (from pin M). A connection to pin L and using the corrected program to test readback from "micro_11_apr_1979_text_syn_read_program_AIM65.pdf" only displays the "N" on either AIM 65 system. The cassette interface potentiometers are sealed in one of the units by the manufacturer and have never been changed as far as we can tell. Is there anything we could try to get reading from tape to work? We are running our of ideas. Is there any way to visualize the incoming signal through a small program other than the one from the magazine?
>
> Kind regards from Basel
>
> Juergen
>

My reply:

My first thought is that the power isn't right, the cassette needs an extra line I believe 12V, but I have to check. I have these notes: Corrections to Guide which talks about the cassette test routine being in error. I assume the PDF you're referencing corrects this.

I don't know where micro_11_apr_1979_text_syn_read_program_AIM65.pdf is located (on this site?) so I will have to consult an original copy of the magazine and get back to you.


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