edwinmuth.com Edwin Muth

Cordless - The core products which the business was built upon

When the FCC allowed an additional 15 channels to be populated with the 46/49 MHz cordless transmitters, the use of frequency synthesizer in lieu of crystals became standard. These designs were simple, but the pressure was to cost effectively manufacture a mass market product. Engineering costs were far lower than materials costs, and an engineer could earn his or her salary on a ten cent per unit cost reduction.

I recall a very successful program was to combine all the analog circuits into a single device, which saved 50 cents or so in the bill of materials. The integrated circuit was in incredible success deployed through the entire product line. This IC was lovingly called the junk chip, because if swept up all the ancillary analog circuits in the phone and integrated the junk into one device.

The next step was to design a digital transceiver to improve the quality of audio reception at 46/49 MHz, above and beyond the FM modulation capabilities. Some of the techniques learned in digital satellite systems engineering would prove useful, such as QAM modulation, error correction, and speech coding.. State of the art techniques for low cost demodulation in a minimal gate count were developed for carrier demodulation and decimation, and applied using novel digital circuit architecture. The range of the system would be extended. The system design was redeployed to the 900 MHz ISM band eventually.

Most of the product line, therefore, would be based on the FM modulators, with some analog voice processing, while the digital effort would be applied to advanced cordless. The innovations in the product line would come from minimal cost architecture, and integration into ICs which would save external components count. The most successful cost engineering effort was actually a very simple IC design, inspiringly labelled the "junk chip". We contracted our semiconductor vendor and I specified a three chip set architecture fro the whole telephone. This allowed all functions to fit in a single board and reduce manufacturing costs greatly. The trend for silicon integration was a firm belief on which our roadmap plans were based, and our partnership with the Silicon vendors was key to our success. The relationship was strategic and mutually beneficial.

The success of the product depended on a number of efficient operations in the factory, as well as a strong partnership in purchasing. One of the challenges in the business was the shift from an external factory strategy to an internal strategy. I remember achieving in four days the same work in our taiwan OEM factories as it took people one or two weeks in our owned factories. And, later, these inefficiencies would prove deadly for the overall business. I wished many times that a healthier balance of internal and external supply had been part of the strategy.

The "gain more freedom" ad slogan found in the above picture is a reflection of the novelty of the products at the time. The market was developing very fast and soon the cordless category would supercede the corded telephones sales. The consumer, in any market, decides which of the innovation products and services sell through.

The 4200/ 4300/4310 / 4600 series of cordless phones would displace the early designs which had successfully launched the business. These new designs replaced an external design, and the manufacturing OEM vendor was asked to produce it. The older products were dropped and replaced with this new line.

This was a low end, high volume product family which took the market over. Consumer products rated this #1 and best quality and value.

Millions of these were sold, using my design and that of others on the team. Partnership with the production factories and purchasing organizations were formed in multidisciplinary teams joined for the purpose of a successful product. The teams went through a gated development process, and success was determined by product success, not functional organization metrics.

The phone met all safety and performance requirements, but this design was simple. There were shortcuts in interference performance, but the range and quality was what the customer wanted. It would be produced in three or four factories in Taiwan, Singapore, Hong Kong, and Malaysia, the ROI was excellent.