Computer Cassette Recorders - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

duncanlowe · 19th May 2020, 12:41 pm

Regarding the auto stop issue. This may be related to the tape counter not running. I have seen one design where there was a magnet mounted on the wheel that drove the tape counter such that as it rotated it operated a reed switch. The control system would detect the lack of pulses from the reed switch and stop the player. When in use, you could actually hear the reed switch ticking.

TonyDuell · 19th May 2020, 4:32 pm

TRS-80 was a name used for all sorts of Tandy computer products (it came from 'Tandy/Radio Shack (Z)80', the Z80 being the processor in many of their computers). Yes, they badged some cassette recoders 'TRS-80' too, they were suitable for use with their computers.

But there should be another model number on it, either CTRnn (Cassette Tape Recorder) or CCRnn (Computer Cassette Recorder). I can see if I have any information (like a circuit diagram) for it if you post the model number

Bit of trivia... The TRS-80 machines had a 5 pin DIN socket for the cassette interface. Ground on pin 2, the signals on 4 and 5 (I forget which is input and which is output) and motor control on 1 and 3. The same pinout was used on the UK Dragon computers (not too surprising, they were similar to the TRS-80 Color Computer, both being based on the same Motorola application note for the 6883 SAM chip). And on a very well-known machine. The IBM5150 (original IBM PC).

Eidolon · 20th May 2020, 4:12 pm

Radio Shack TRS-80 / CCR-81 Model 26-1208A written on the bottom of the deck

TonyDuell · 20th May 2020, 4:23 pm

Right... I know that unit, I think I have one somewhere.

I found the user manual on-line somewhere. It includes the circuit diagram but no other service information. If you want it, I can send you a copy (just PM me with your e-mail address).

19th May 2020, 12:41 pm	#21
duncanlowe Nonode Join Date: Jan 2016 Location: Stafford, Staffs. UK. Posts: 2,531	Re: Computer Cassette Recorders Regarding the auto stop issue. This may be related to the tape counter not running. I have seen one design where there was a magnet mounted on the wheel that drove the tape counter such that as it rotated it operated a reed switch. The control system would detect the lack of pulses from the reed switch and stop the player. When in use, you could actually hear the reed switch ticking.

19th May 2020, 4:32 pm	#22
TonyDuell Dekatron Join Date: Jun 2015 Location: Biggin Hill, London, UK. Posts: 5,208	Re: Computer Cassette Recorders TRS-80 was a name used for all sorts of Tandy computer products (it came from 'Tandy/Radio Shack (Z)80', the Z80 being the processor in many of their computers). Yes, they badged some cassette recoders 'TRS-80' too, they were suitable for use with their computers. But there should be another model number on it, either CTRnn (Cassette Tape Recorder) or CCRnn (Computer Cassette Recorder). I can see if I have any information (like a circuit diagram) for it if you post the model number Bit of trivia... The TRS-80 machines had a 5 pin DIN socket for the cassette interface. Ground on pin 2, the signals on 4 and 5 (I forget which is input and which is output) and motor control on 1 and 3. The same pinout was used on the UK Dragon computers (not too surprising, they were similar to the TRS-80 Color Computer, both being based on the same Motorola application note for the 6883 SAM chip). And on a very well-known machine. The IBM5150 (original IBM PC).

20th May 2020, 4:12 pm	#23
Eidolon Hexode Join Date: Dec 2012 Location: Worcester, Worcs, UK. Posts: 257	Re: Computer Cassette Recorders Radio Shack TRS-80 / CCR-81 Model 26-1208A written on the bottom of the deck

20th May 2020, 4:23 pm	#24
TonyDuell Dekatron Join Date: Jun 2015 Location: Biggin Hill, London, UK. Posts: 5,208	Re: Computer Cassette Recorders Right... I know that unit, I think I have one somewhere. I found the user manual on-line somewhere. It includes the circuit diagram but no other service information. If you want it, I can send you a copy (just PM me with your e-mail address).