411 on the 410

[clh333]

To augment a recently acquired XL800 I obtained a "not working" 410 cassette recorder from an eBay sale.  On first inspection I found that the unit did not appear to operate at all.  I disassembled and found the belts stretched, as suspected, and obtained a replacement kit from console5.  My thanks to the OP who posted this guide on replacing the rewind belt.

After replacing the belts I could activate the motor to advance and rewind, and activate play and record keys (as long as a tape was present), but neither play nor record caused the motor to turn.  I'm getting 12+VAC from the transformer, across the two yellow leads, and 6+VAC across either yellow lead and the blue lead.  I have verified that the switch actuated by the "play" button has continuity and is making contact, so my initial guess was a bad transistor or capacitor.

 

However I read in the Atari Field Service Manual (FSM) for the 410 that the Atari interface cable provides motor control (+5VDC).  This suggests that the cassette deck will not operate independent of a connection to the Atari 800XL.  I had previously read that the cassette motor COULD be controlled by the XL; i.e. poke a value to start and stop the motor, but this factoid would mean that the deck HAS to be connected to operate.  This is contrary to my experience with TRS decks which employ a special plug to defeat keypad control.

 

I'd like to test this hypothesis by furnishing an external +5VDC and ground but don't know which leads are which on the plug or the PCB (and I don't want to risk the XL by connecting to it).  The FSM references components but the PCB is unmarked.  Does anyone know what leads do what?

 

Thanks for your responses.

-CH-

[ClausB]

Yes, there's a motor control signal in the SIO port to enable the 410. Here's an article by my former boss:

https://www.atarimagazines.com/v1n4/audiowhileyoucload.html

 

Edit: sorry, that didn't fully answer your question. Put 5V on the Motor Control line to enable playing. See the pinout diagram in the article.

Edited October 23, 2021 by ClausB

[clh333]

The FSM schematic at the back of the manual shows an orange trace carrying +5VDC and labeled "motor control".  A black lead is labeled ground.  Duh!

 

With the AC line powered and the "play" button engaged I touched probes to the solder pads leading to the orange and black leads from the interface cable and observed the motor turn at record / playback speed as long as +5VDC was present.  The probes carried +5VDC to the orange pad and ground (0VDC) to the black pad from a DC supply.

 

-CH-

[clh333]

I had to disassemble / reassemble the unit several times before I got the rewind belt adjusted properly.  I'm not sure what I was doing wrong but that was the fussiest adjustment.  I also cleaned all the roller rubber with lighter fluid (benzine).

 

At length I was able to advance and rewind the tape at will, with the counter tracking tape position, and under command of the XL save and recall a BASIC program.

 

Thanks to all who contributed their suggestions.

-CH-

[clh333]

One last question:  The FSM mentions use of a test cassette for calibration of the 410.  I haven't found a source file for this; does anyone know of a place to download?  Thanks.

-CH-

[+kheller2]

1 hour ago, clh333 said:

One last question:  The FSM mentions use of a test cassette for calibration of the 410.  I haven't found a source file for this; does anyone know of a place to download?  Thanks.

-CH-

I’ll let someone else chime in, but if the tape is for head calibration then using a copy is somewhat worthless (since the calibration would be modified by the reading of a head that made the copy and writing by another head) similar to why copies of disk head calibration disks are off.  
 

 

[_The Doctor__]

correct, the test calibration tape has to be an original, any duplication and you get the new recording devices tracks... there are calibration test tapes for/from most manufacturers and was something that audiophiles actually did and or had done every couple of years as part of maintenance and service or their decks.