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SiriusHardware · 11th Jan 2021, 2:59 pm

Good find, I've never seen that before.

I'll give the latest version a test drive tonight, thanks for sorting that out. With any luck the new lead-in silence will let it work with the little MP3 player.

The final SOC TI PCB does have a voltage divider of sorts on the output (has to really, to take the TTL-level signal out from a logic IC down to something small enough to feed into a microphone input).

To judge from what I found earlier it looks as though they decided to go with a line-level tone input, maybe not the wisest choice as most of the actual tape machines likely to be used would only have had a low-impedance 'phone' output.

11th Jan 2021, 2:59 pm	#67
SiriusHardware Dekatron Join Date: Aug 2011 Location: Newcastle, Tyne and Wear, UK. Posts: 11,567	Re: MK14 Tape Interface Good find, I've never seen that before. I'll give the latest version a test drive tonight, thanks for sorting that out. With any luck the new lead-in silence will let it work with the little MP3 player. The final SOC TI PCB does have a voltage divider of sorts on the output (has to really, to take the TTL-level signal out from a logic IC down to something small enough to feed into a microphone input). To judge from what I found earlier it looks as though they decided to go with a line-level tone input, maybe not the wisest choice as most of the actual tape machines likely to be used would only have had a low-impedance 'phone' output.