PHOTON TECHNOLOGIES: Photovoltaic/LED Product Design and Consulting
P.O. Box 14457
Bradenton, FL 34280
Phone: 941-795-5225

PHOTON TECHNOLOGIES High Performance Photovoltaic
and LED Product Design and Consulting Services

Specializing in Photovoltaic, Solar Powered and Recharged products and devices, PHOTON TECHNOLOGIES, since 1992, has been in the forefront of Photovoltaic and LED technologies.

Below is just one of our Case Stories about how we were presented with a design problem and solved it to create a viable, producible and profitable product for the client.

We welcome your inquiries on how we might add value to your product line.

Robert J. Mulligan-President
Bradenton, FL

Ref: Solar Recharged/Powered Radio Development Project

Mr. J--- D---s
------- ---- CORPORATION
100 -----------
Athens, GA -----
Phone: ----------
Fax: ------------

From: Robert Mulligan

Date: 6/10/99

Dear Mr. D---s,

Per our continuing conversations regarding the feasibility of your firm producing some type of solar powered radio for the U.S., European and the third-world areas, we believe that we have designed an inexpensive and simple to produce radio product that meets your design criteria.

We will shipping the prototype radio to you by UPS Overnight on Thursday for a Friday delivery.

Below are photos and design concepts of the radio plus a few additional ideas for your staff to consider.

Everything shown below is quite simple to produce either here in the United States, Mexico or in the Far East.

We present it here in this Website format so that your Sales, Marketing, Engineering and Production personnel may review it prior to our next meeting, thereby saving time and additional expense.

As noted in my prior fax, the radio is now equipped with two NiCad Rechargeable batteries instead of the non-rechargeable Alkaline batteries. This allows the radio to be recharge both from the solar panel and from a common AC/DC wall charger. The prime concept, however, is that the radio could be simply left in a sunny window and be recharged and ready to use without the need for a "wall" to provide "wall-charging".

The Flexible Plastic Solar Panels do not require you to do any Retooling. Just mold your EXISTING RADIO in CLEAR PLASTIC instead of a colored plastic. The Flexible, Plastic Solar Panel is simply placed behind the clear backing housing.

For the mock-up, we just glued the thin Solar Panel to the back of the Radio. As noted, in a production radio, we would suggest that the panel be mounted behind a clear back plate.

Since most small, battery powered Radios are molded in two halves, a front and a back, just mold the back in clear plastic with the Solar Panel showing through the back.

The front of the radio could still be molded in a color.

Easy to Adapt Your Standard Radio to Solar Powered:
As shown below, just do the following and your plain Radio, becomes "Self-Charging" or "Self-Powered" and of a much higher value to the consumer and the retailer:

1-Replace your existing two 1.5 volt Non-Rechargeable batteries with two 1.2 volt NiCad batteries.

2-Add +/- Wire Leads to the two copper (easy to solder!) +/- contacts at each end of the ITF Flexible, Plastic Solar Panel and add a Blocking Diode to the Positive Wire Lead (acts like a One-Way Valve to prevent power drain from the Solar Panel to the Batteries at night or in darkened condition).

3-Attach the Positive (with the Blocking Diode) and the Negative Solar Panel wire leads to the battery contacts. This can be by soldering or a simple insert between the battery contact ends and the metal contacts within the Radio.

4-Install the Solar Panel inside of the clear case and close the cover.

Your existing Radio is now, "Self-Charging" and "Self-Powered"!

Very easy to do...

Below are photos of the mock-up Radio.

The batteries may be recharged either by the 3.0 volt/40 mA Solar Panel that is an integral unit of the Radio, or with the 3.0 volt/80 mA Solar Panel that we installed in a folding Denim Cover. (See Notes on the Plug-In Solar Panel). This plug-in Flexible Solar Panel has a DC Power Cable that plugs into the existing jack on the side of the radio.

One of the nice features of this arrangement is that the integrally mounted 3.0 volt/40 mA Solar Panel or the external, plug-in Solar Panel will power the Radio directly when the Radio is in the Sun. Either will directly operate the Radio even when the batteries are removed.

Most small Radio circuits operate at about 15 mA so, even in lower light levels, our single 40 mA panel will directly power the Radio, without the batteries.

The advantage of the larger, plug-in radio with its higher mA output, 80 mA, is that this will allow the radio to be played even in quite cloudy conditions. (See Notes on the Plug-In Solar Panel).

More Power:
For more Recharging or Powering power, any radio with a DC Wall Charger input can be equipped with a separate Solar Panel that plugs into the DC jack, just like the "Wall Charger" except you don't need the "Wall", just the Sun.

We show an easy to make folding Solar Charger that has two of our ITF Flexible Plastic Solar Panels connected in PARALLEL to double the current but leaves the voltage the same, 3.0 volts.

The larger Solar Panel area allows the Radio to be used and directly operated from the panel in lower light level environments and allows for faster recharging.

Adding LED Ilumination:
As a demonstration of an inexpensive addition to this Solar Radio product, we have also added two amber Ultra-Bright LED's to the Radio to allow it to be a dual-purpose product. This expands the markets for the Radio, with a higher profit level and a very low additional cost.

The locations of the LED's are just for the mock-up demonstration and the assembly is a bit rough, but the point is made that you can add lighting to your Solar Radio product in a variety of ways to enhance the sales and the markets.

As shown, the amber oval LED at the end of the Radio is a "Spot-Light" LED which will provide a fairly good flashlight effect for locating lost items, keys, illuminating dark closets, emergency signaling and for dark pathway lighting.

If the Radio was equipped with a simple amber, Ultra-Bright LED, it could provide "candle-like" room illumination in case of a power failure without to use the high-power demand primary flashlight bulb. (Much safer than candles!).

Since Ultra-Bright LED's in amber colors, only use about 25 mA, and have an unlimited lifetime (be sure to use a current reducing resistor), the LED would allow the user to illuminate a pathway or read a book at night with very low power drain. For example, if the LED draws 25 mA and the battery capacity is 500 mA, you should be able to get about 20 hours of light from it. This would be great f or campers!

The inexpensive Ultra-Bright LED may be installed within the reflector or in a molded area of the Radio. This doubles the use of your Solar Radio and expands its markets.

The other Amber Ultra-Bright LED is a much wider beam. We have placed this on the front of the Radio so that the Radio may be laid down on its back so that the LED is facing up. This wider beam LED will cast a softer beam and will provide a bright, candle-like effect in a tent, boat or campsite (or for Y2K home illumination).

We have included a switch at one end to choose between the spot-light LED or the Candle LED. In a production Solar Radio, the switch would be much smaller. The concept is easy to see, however.

Costs of Solar Adaptation of Your Radio Product:
To add the features that we have shown in the photos, below is an estimated summary:

1 each:
ITF 3.0 volt/40 mA Flexible Thin-Film Solar Panel: Under $3.00

1 each:
Blocking Diode: Under $0.10

1 each:
Current Limiting Resistor: Under $0.05

1 each:
Amber Ultra Bright "Spot-Light LED: Under $0.50

1 each:
Amber Ultra Bright "Candle-Light LED: Under $0.50

1 each:
Three-Way Switch: Under $0.50

So to add both Solar Recharging AND an amber Ultra-Bright LED for a Spot-Light and a Candle-Light, the Cost is under $5.00. The cost of the two NiCad Batteries, is probably equal to the cost of the two Alkaline batteries presently in the Radio so the overall cost of making a Radio into a unique and highly saleable product, at a very good profit margin is quite low.

We deal with quite a number of firms who have discovered that if they take ordinary, low-profit products, and "SOLARIZE" them, they increase the market, usefulness and radically increase the profit potential of this product. It places their produce out in front of their competition at a very low cost.

Advertising your Solar Radio Product:
A Solar Powered Radio can be promoted in many magazine and publications for very little cost because of the "uniqueness" of the product. Publications are always looking for new products to write about, especially if they represent a new way to save energy.

Your new Solar Radio product can be advertised, highlighting the following assets:

Saves Energy

Safe and Friendly to the Environment

Saves the Cost and Disposal of "Throw-Away" Batteries


Safer for Small Children to be Around (no "Wall-Chargers" for the Kids to Investigate)

A Product that "Just Makes Sense".

The radio product that we designed for your firm offers a number of features including the AM/FM function, plus two types of illumination. It not only would appeal to the traditional consumer market, but also to emergency and third-world markets.

Let us know if we may offer further assistance to your project and thank you for engaging PHOTON TECHNOLOGIES to design your proposed radio product.

We look forward to your reply,

Robert Mulligan

August 18th, 1999

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