Penny's Computer Book from Inspector Gadget

Anyone who has ever watched the cartoon has probably said "Wow, I want one of those!". Gadget's neice Penny had a device that looked like a very large book with an attached headset, but the pages were actually displays and controls for a variety of electronic monitoring and control systems that she used for spying, communication, control, and jamming. During the early 80's none of that was really practical, but with today's surface mount technology, microcontrollers, and wafer thin displays, I think I might want to give something like that a crack.

Right now I'm trying to determine what capabilities the device should have and a basic design architecture. Here is what I'm kicking around so far.

The spine of the book will consist of a 12v battery supply, probably AA alkalines since I have hundreds of them already. A power supply bus will tap the supply at 1.5v intervals. Regulators will be used on the individual circuit "pages" if needed. On the top of the spine a telescoping antenna will be mounted for RF transmission and reception. Infrared LED's and a phototransistor (shielded from each other of course) will be at the top edge of the spine for infrared control and reception. I might include an infrared laser (space permitting) for long range control/jamming. Aiming it would be tricky, which might be reserved for the headset. At the bottom of the spine would be a headset jack for sound and video I/O.

The covers will be where the electronics for the shared circuitry are housed. I'll have modular audio amplifiers, digital recorder (I already have one thin enough, even takes an SD card), radio receiver(s) and transmitters capable of being tuned to a wide range of frequencies, and a microcontroller to interface with the controls on the pages.

Using the controls on the pages, the user will be able to connect the modules in any configuration. For instance if they wanted to transmit voice disguised audio, they could turn to the voice disguiser page and push the appropriate pads to link its input to the headset mic and output to the FM transmitter.

What I'm asking for is input on what capabilities this device should have and suggestions on how to build the modules, pages, etc. I think with current surface mount technology and incorporation of as much prefab consumer electronics as possible this should be feasible. It would certainly be the ultimate geek toy if I can pull it off.

I don't like to tell you, but it was a cartoon!.

Most of the facilities it had aren't practical or possible - and would also be illegal to attempt.

"illegal to attempt" is not true. It is legal to build FM wireless microphones with appropriate power outputs, voice processors, radio receivers, infrared remote controls/receivers, digital audio recorders, etc. Using these devices in an illegal manner would not be appropriate.

Practicality is part of what I'm trying to determine here. Through discussion we should be able to figure out what is possible.

displays is going to be the big cost ... wafer thin equals mega bucks

how about building these various modules to be controlled via usb or bluetooth, from a regular tablet PC?

I have an old Palm Vx that can be used as a display module. It is REALLY thin, but monochrome. I have an NTSC viewfinder from an old camcorder that can be hacked into the headset, but I'd also like to have display capability in the book as well.

I like the USB idea. I have a drugstore digital camera board which is also very small and has a USB interface, so does my digital audio recorder.

I've decided to take an intermediate step first. I'm going to design a probably quite large version with regular components that I have on hand before I do an advanced version with surface mount PCBs.

The advanced version will have microcontrollers linking the modules together, but for now I'm going to have a central bus along the inside of the spine consisting of a couple of ribbon cables. Wires from the inside edge of the pages will connect into the ribbon cable. Controls on the pages will connect the modules to each other and the I/O. In the prototype this is going to create quite a bit of redundancy since each function page will be using switches that are duplicated on other pages.

I'll start out easy and work up from there. Right now I'm going to just do the power supply and audio circuits, using my available (but quite obsolete) component supply. Performance won't be great, but hopefully I can learn enough to improve the final version.

Here is the current plan:

Build power supply for the spine consisting of 8 AA alkaline batteries, tapped at 1.5v,3v,4.5v,6v,9v,12v and +6/-6. QUESTION: Should I put a capacitor power suppy noise filter in here consisting of 100uF,1uF, and .1uF caps, or use power filtering on the individual modules?

Build the spine itself, reserving space alongside the power supply for an antenna and other future additions that might need to extend along the spine, as well as connector blocks at the bottom and top. I'm estimating a spine 14" high and 3 1/2" wide. This is very large, but Penny's book was about 1/3 the size of the kid anyway. The final version would be much smaller.

Run a ribbon cable with ground and power taps. I figure at least 12 conductors to allow for future expansion.

I'll start on the circuits for the front cover. For now I'll have 4 audio preamps and 2 power amps. I'll get this using a 324 for the preamps and two 386's for the power amps (yeah, I know, totally obsolete, but at least I won't be wasting decent ICs while I'm figuring out what I'm doing). Unless someone has a better idea, I'm going to have to mount the slider pots to adjust the negative feedback on the preamps on the inside front cover to prevent the need to switch in separate pots to the circuits on each page that uses them. Switches on the pages will route the inputs and outputs to and from the bus. The final version would just use control pads on the pages and have the microcontrollers handle the traffic. I find I can make circuits relatively flat and compact by laying out the components much like they are arranged on a schematic and running wires between them. 22 guage solid wire should add some rigidity as well, and stranded wires will run to the cables on the spine. I hope I'm not being too optimistic by thinking I can keep the thickness of the covers down to 1/2" using non-surface mount components. This would leave 2 1/2" for pages.

Any feedback (besides "It was a cartoon and you're a tard") would be appreciated. I'll post some pics when I'm done with the spine.

I love it when fictional devices slowly creep into reality, keeps life interesting.

We're all walking around with star-trek communicators in the form of our flip-open cellphones. Penny's computer book seems like the next logical choice.


I'm concerned with sturdiness of the pages. While the spine and covers can be reinforced how will you deal with stresses on the pages? Lets say i hold the book open by the covers and start shaking, the pages might rip off the spine due to their own inertia.


On a different topic: From what i understand of your system, all the hardware is crammed into the spine and the covers while the pages merely contain controls. So the system is essentially "software emulation" based where the various functions are defined in software, but the pages give the illusion that each page has its own function. am i right?

Another suggestion: Can the covers themselves be solar panels allowing the book to self-charge? Sure it would be VERY slow but hey, it might be worth having. Would certainly up the geek factor a few notches.

Suggestion for functions: is there a tracker/transmitter module? a small device, maybe disguised as a "bookmark" that is magnetic (or has double sided tape) and is actually a tracking device. Once attached to target the book can track its location.

Something that's not too difficult to implement with modern microcontrollers is the standard voltmeter/ammeter/ohmmeter package. For more sophistication maybe even a capacitance and inductance meter. The probes might be difficult to hide with your limited space. An idea might be to have two pieces of ribbon that actually hide within them conductive foil/wire. Most big books have ribbons to serve as place holders or bookmarks but yours might actually serve as the probes for the measurement circuit because of the foil/wire inside.

If you have a third ribbon/probe you might even be able to incorporate voltametry/amperometry/coulometry systems and have the book perform portable chemical analysis of unknown substances.

a hole in the back cover might hide an ultrasonic distance measuring unit.

How about some temperature and air pressure sensors?

Very expensive and maybe a later add-on if you can: a high frequency ADC module. this can serve as an oscilloscope function but can also be used to perform on the spot frequency analysis of various signals. With it you might even be able to incorporate a basic nuclear magnetic resonance machine into the book. although not capable of imaging someone's brain it might be able to determine the proton content of an unknown liquid, allowing you determine if its alcohol or gasoline.

as usual, no usb enabled gizmo is complete without 1-100 gigabytes of storage when you're just too cool to use a USB key.

And no electrical device, no matter is how sophisticated, is cool without some blinky lights that do absolutely nothing.

I've started construction on the 4 channel audio preamp (I'm waiting for parts for the power supply, so started on something else). Already something is dawning on me. There is going to be MUCH more wiring than there is circuitry. Significant shielding will be required. The covers will have an aluminum plate in them, and I'll probably do that for the pages as well. That will also address the issue of strength. This thing is going to be heavy. You'd need a backback to lug it around, but then again so did Penny. The final version will be smaller and lighter (I hope).

It is turning out a bit thinner than I thought, I can probably keep the covers down to 1/2", no thicker than the pages. Thickness will vary in places, so standoffs will be needed. Maybe some thick foam strips on the edges of the pages and the inside of the covers.

This sounds like an interseting project. Be sure to post pictures of your work when it gets close to being completed.

Things are actually progressing quite quickly (although I still can't finish the spine because Futurlec is being SLOW). I have the 4 channel audio preamp module completed, as well as 2 audio power amps. They are just flattened mats of gaffer's tape with wires coming out right now, but they are tested and working.

wow this would be such a cool project if i thought it possible

I've decided to include the controls on the pages where their electronics are located to cut down on the bus wiring and number of switches needed. I'm already out of switches!

to cut down on wiring, would it work if you could connect the switches and controls to a multiplexer/demultiplexer system? might reduce the number of connections to your bus.

Another alternative is to connect your switches to a parallel to serial converter, run the signals on a serial bus, and then convert back into parallel output which it reaches to appropriate part. If you're using a microcontroller it might even be more straightforward just to decode the serial data in software.

the converters could be located on the pages beside the switches and thus still leave your primary hardware in the pages.

The "data" is going to be a number of different types of signals including audio and video. For the advanced version it sounds like a good idea for the control signals though.

robotgangsta said:

wow this would be such a cool project if i thought it possible

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My thoughts exactly - but it appears he's only doing the simple practical parts, none of the parts which made it cool.

Come on guys, stop bashing him.

Even the greatest of accomplishments must start with the smallest of steps. Even he if gets nowhere he might make something useful along the way. A great many of inventions where created this way. Star trek communicators at one time were laughed at, now everybody has pocket cellphones even smaller than the bohemian brick that Kirk used.

Penny's actual book is impossible to make. for one thing i don't think we have commercially avaliable flexible computers that are paper thin... But i think his actual intention is to create a device "inspired" by penny's book.

Of all the crazy ideas i've seen floated on this board, where 10 is perpetual motion and 0 is a flashlight, this guy's book does NOT score a 10.

Glyph said:

Come on guys, stop bashing him.

Even the greatest of accomplishments must start with the smallest of steps. Even he if gets nowhere he might make something useful along the way. A great many of inventions where created this way. Star trek communicators at one time were laughed at, now everybody has pocket cellphones even smaller than the bohemian brick that Kirk used.

Penny's actual book is impossible to make. for one thing i don't think we have commercially avaliable flexible computers that are paper thin... But i think his actual intention is to create a device "inspired" by penny's book.

Of all the crazy ideas i've seen floated on this board, where 10 is perpetual motion and 0 is a flashlight, this guy's book does NOT score a 10.

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I don't think anyone is 'bashing him', just applying a little reality, and I doubt anyone has any problems with it as a project, as far as it goes. As suggested, some parts of it are easily practical - but the really cool parts are still purely fictional, and probably always will be?.

As for the StarTrek communicators, there was really nothing particularly special about them even back in the days it was made, perhaps slightly smaller than available back then?, but it was only a walkie-talkie. A modern cellular phone and network is FAR beyond anything in StarTrek, as are modern computers.

I'm a BIG SciFi fan, and two 'predictions' I've never seen in SciFi were cellular phones and home computers.

Was wondering what the outcome was of this thread. noticed everyone stopped posting back in 07. was wondering if you succeeded. would love to see a photo or video if you did.

I abandoned this project after the audio stage was completed, even that was a bit unruly. A raspberry pi, a transceiver chip, and a phone app could do this now. It was interesting to kick around though.