Ian, Thank you for information on Telegen billing tone filters.
My billing tone filter concerns are not the ability to design and/or provide Swiss or German filters. It is more a case of expressing my concerns about harmonizing EU standards like TBR 21. If Switzerland, Germany or any other country is going to claim harmonization they can't have exceptions to standards. They are not harmonized until exceptions are eliminated. In the Swiss and German case filters could be provided in the telecom jack. This would eliminate the need to design a special modem for each country. I don't understand how any EU country can claim to have harmonized standards when there are exceptions to the standards. In the Swiss and Germany case if the filters were in the telco jack their consumers would have a more sources of telecom devices at lower cost. This would help to create a climate of laisse faire development in telecom equipment. Which would ultimately create competition, innovative development, lower costs, more production, corporate profits and tax revenue. What I am designing is a world wide DAA for an HPC. The DAA is a dongle. Adding your dongle filter in series with this dongle would not be an applications of convenience and it would be harder to sell. I designed filters in the dongle for both countries. This means manufacturing separate dongles for each country. Which translates into special compliance approvals, manufacturing , testing and stocking. The bottom line, it costs more to support those countries. So, an HPC with these DAA's costs more. Which probably means fewer sales in each country. In my opinion exceptions to EU standards inhibit technology and are barriers to free trade. Regards, Duane
