Internal AtariVox+ install with power switch and no case cutting

[+x=usr(1536)]

If you have a 7800, an AtariVox, a desire to ditch the external speakers that the AtariVox typically needs, and don't want it interfering with your Player 2 joystick's inputs... Read on 

 

Before getting into the implementation, there are three things that need to be stated:

• The assistance of @juansolo, @marauder666, and @-^CrossBow^- is very greatly appreciated.  Their help in a couple of places where I was stuck was absolutely essential, and without it this would not be a fully-functional project in the way that I wanted it to be.  Thank you, folks 
• Additional thanks to @spspspsp for the thread in which an Adafruit level shifter was used to isolate the AtariVox from the joystick port.
• There are many ways of accomplishing this.  This is just the one that I chose; if someone has done or wants to do it differently, more power to them in my book.

Links to the relevant threads will be provided at the end of the post. 

 

Please note that the photos in this post are showing what is essentially a rough cut of how the final version will end up.  The wiring's untidy at best, most of the bits & pieces that were installed still have to be permanently anchored, and various locations need a good scrubbing.  When all of that will happen is unknown, so I figured that it was at least worth getting the information out there for anyone who may be looking to do something similar while I wait for more DuPont connectors to arrive.

 

Before diving in, there are three main components that will be needed:

1. One AtariVox+ Speech Synthesizer
2. One Adafruit 4-channel I2C-safe Bi-directional Logic Level Converter - BSS138
3. One Miniature Capacitive Touch Switch (these are apparently only sold in pairs; I've yet to see single ones for sale)

And, in addition to those, the usual gamut of wires (with female DuPont connectors), straight and right-angled 2.54mm pin headers, a 6.8kΩ resistor, solder, a soldering iron, double-sided tape, etc.

 

Substituting parts is discouraged, especially where the capacitive switch is concerned.  A few different types were tried before settling on the one that's listed, and the TTP223-based switches in particular will not work as they cannot handle the current needed to drive the AtariVox.

 

Additionally, the behaviour of the switch can be changed via jumpers located on it.  It is not recommended to do this.  Due to the potential for damage if the switch has other than default behaviour, it's best to just use it as it comes out of the box.

 

Step one: prepare the AtariVox.  This involves first turning the volume pot all the way down (anticlockwise), then desoldering both the female DB-9 connector and the headphone jack from the board followed by adding pin headers in their place.  When that's done, it should look something like this:

 

 

A couple of points regarding the above photograph:

• In the location where the joystick connector was originally, there are number markings visible.  These do not denote the pin numbers on the Atarivox board, but rather the pin numbers on the console's joystick port to which the Atarivox will connect that particular pin.
• At around the one o'clock position, note that there is only one right-angle pin coming off of the audio output nearest the small blue capacitors.  A trace on the top side of the board (not visible when the headphone jack is still installed) connects this pad to a second pad offset from it.  Only take audio output from the pin shown.  Do not use the other one, or bridge them.

Moving on to the level shifter board:

 

This board has two sides: HV (High Voltage) and LV (Low Voltage).  Looking at the top side of the board, HV is on the right and LV is on the left.  In this case, the same voltage will be used on both sides.  Consider the HV side to be the connection to switched power and the joystick port; LV will carry power, ground, and signals to the AtariVox side.

 

Step 1: install right-angle headers on both the HV and LV sides:

 

 

And bridge the topmost connection on the underside of the board.  I went with a header pin, but it's your choice as to how you do this:

 

 

Next, wire up the switch.  Brown is GND, red is +5VDC from the 7800, orange is +5VDC switched output.  Colours are entirely your call, and yes, it's already mounted in this photo:

 

 

Here's where we get to the meat of the matter.

 

Firstly, the takeoffs from the Player 2 joystick port that will pull back to the level shifter board need to be soldered in:

 

 

And the pin headers for the supply to the power switch need to be added to the +5VDC (red) and GND (brown) rails:

 

 

Now connect the switch.  Gorilla Tough and Clear mounting tape was used to hold the switch in place.  Note that the output from the switch (orange) runs to the topmost pin on the HV side of the level shifter:

 

 

 

Next, connect the joystick port wiring to the HV side of the level shifter board:

 

 

The one thing that hasn't been mentioned yet is what to do with the brown (ground) wire at the bottom of that row of pins.  We'll come back to that.  Spoiler alert: it'll also turn up in the next photo, in which its LV side is connected to the AtariVox itself (+5VDC is red rather than orange, but is still at the top of the LV row):

 

 

Time to explain a bit about what's going on here.

 

The switch takes its power (+5VDC, red; GND, brown) from rails on the PCB.  From the switch, the +5VDC output (orange) connects to the topmost pin on the level shifter's HV side.  GND connects to the lowest pin on the HV side and runs to one of the ground pins on the UAV.

 

On the LV side, the topmost pin runs to the +5VDC input (red) at pin 7 on the AtariVox; ground runs to pin 8 (brown) directly next to it.

 

The connections from the HV to LV side are one-to-one.  Look at the wiring colours used on the four pins in the middle of both sides:

 

 

Blue comes in from pin 1 on the joystick port to the HV side.  It's then output on the corresponding blue wire on the LV side, which in turn goes to pin 1 on the AtariVox.  Green is pin 2 all the way through, and yellow and orange are 3 and 4, respectively.

 

Here's a bird's-eye view, which may help with illustrating how it all goes together:

 

 

Which neatly brings us to the UAV.

 

You may or may not have one of these installed.  If you do, it may be a good ground point to use for the HV ground.  If you don't, you'll want to find a decent ground.  The same rail that the switch ground is connected to is a possibility - as is the one in the middle of the PCB.  It's the one on the right-hand side of the two fat rails running down the centre.

 

Now for the audio, which also has its own set of UAV-related peculiarities.  Yay!

 

In the above picture, there is a purple wire running from the audio pin on the AtariVox; this has a 6.8kΩ resistor added to it, and is being pulled back to the positive feed to the audio capacitor on -^Crossbow^-'s 7800 UAV mount board.  The resistor should be placed between two lengths of wire and not soldered directly to the audio cap's positive pad.  Where the wire and resistor (under heat shrink tubing) feed in are visible at about the six o'clock position below.  For a clearer view of how the wire is attached to the capacitor's positive pad, click the photo for a larger version:

 

 

If you have one of these boards installed, put the 6.8kΩ resistor in line with the AtariVox' audio output, and solder the end here.  Don't be tempted to use the R5 or R6 pads; there will be problems.  Just trust me on this one.

 

If you do not have one of these boards installed, put the 6.8kΩ resistor in line with the AtariVox' audio output, and tie it in where R5 and R6 are bridged along with their resistors.

 

If you're still on an unmodified, RF-only system, I'm not entirely certain what to tell you.  By all means feel free to ask; people are here who can likely help with that.

 

Now for the good news: you're nearly done.

 

The one remaining thing to take care of is setting the volume level on the AtariVox.  For this, loading a game such as Juno First is recommended as it has speech interspersed with the gameplay.  Play the game to get a feel for where the balance between speech and sound effects are - and remember that you turned the volume on the AtariVox all the way down at the start of this   Just adjust it gradually until you're happy with where it is.  Don't crank it all the way up and work down; that could be bad.  Start low and gradually go high.

 

Enjoy!  And by all means let me know if any of this can be improved or corrected.  My goal in writing this was to gather a bunch of information from different threads into one place and hopefully clarify the process for anyone thinking of doing the same.  Making certain that this is as accurate as possible is a fundamental part of that, so I am more than welcoming of comments.

 

 

For reference, the threads that got me onto this track in the first place were:

 

@juansolo: Atarivox Inside

@marauder666: AtariVox internal install

@spspspsp: Internal AtariVox activated using channel select switch

 

And if you're looking for 7800 or other console mod / repair services in the US, talk to @-^CrossBow^-.  He does excellent work and really knows his stuff.

[+x=usr(1536)]

Now for the important part: how to use all of this 

 

By default, the AtariVox will be powered up when the system is switched on and the, "AtariVox Plus - Ready," message should be heard through the TV speaker(s).  If it isn't, make sure that everything was put together correctly 

 

To disable the AtariVox, all that should be needed is to tap underneath the case directly below where the capacitive switch is.  You'll know if it's off in two possible ways: one, its LED turns off; two, a low-volume downward glissando can be heard from the TV speaker(s) as it powers down.

 

Two things to keep in mind:

1. If you want to disable the AtariVox, preferably do it while the, "Atarivox Plus - Ready," speech is taking place at boot.  Turning it off during gameplay is discouraged.
2. If the AtariVox is turned off, do not turn it back on.  Doing so could potentially harm the TIA, so best to just leave it off.  The safest way to re-enable it is to power-cycle the system.

Other than that, there shouldn't be anything really special about how to use it.

 

One thing that I would be interested in: hearing how well (or otherwise) this works if a Quadtari adapter is plugged in on the Player 1 joystick port.  If you are able to replicate this particular configuration, please let us know how well it does or does not work.

[juansolo]

4 hours ago, x=usr(1536) said:

One thing that I would be interested in: hearing how well (or otherwise) this works if a Quadtari adapter is plugged in on the Player 1 joystick port.  If you are able to replicate this particular configuration, please let us know how well it does or does not work.

In theory it should just work as I believe this is how Al demonstrated Wizard of Wor at some point. So you could have both two players and AtariVox speech. Indeed if a cut down Quadtari (Dualtari?) existed, I'd be interested for that particular scenario.

Edited April 14, 2023 by juansolo