Collaborate Disseminate
A few years ago, I was out at the W6TRW swap meet at the parking lot of Northrop Grumman in Redondo Beach, California. Tucked away between TVs shaped like polar bears and an infinite variety of cell phone chargers and wall warts was a small wooden box. There was a …read more
The Plain Old Telephone Service, or POTS, doesn’t get a lot of love from the average person anymore. Perhaps once in a while a payphone will be of use when a phone battery has died, but by and large many people simply don’t have hardwired phones anymore. However, that doesn’t …read more
Continue reading Reverse Engineering a Telephonic Relay Device
What are the risks of communicating sensitive information using a land line? Once my voice gets digitized does the carrier use encryption during transport?
We have all heard about rogue cell towers (stingray boxes) which ren… Continue reading How secure is a land line phone call?
There is plenty of software which allows a user to input a recipient’s information, and a fake-originator’s information, and the software will complete the caller ID spoof. I’m trying to understand why the telephony stack is … Continue reading Why is caller ID spoofing so simple, and catching offenders so hard?
A bewildering amount of engineering was thrown at the various challenges presented to the United States by the end of World War II and the beginning of the Cold War. From the Interstate Highway System to the population shift from cities to suburbs, infrastructure of all types was being constructed at a rapid pace, fueled by reasonable assessments of extant and future threats seasoned with a dash of paranoia, and funded by bulging federal coffers due to post-war prosperity and booming populations. No project seemed too big, and each pushed the bleeding edge of technology at the time.
Some of …read more
Continue reading Horns Across America: The AT&T Long Lines Network
Most people hate unsolicited calls, and it’s worse in the dead of night when we’re all trying to sleep. Smartphones are easy to configure to block nuisance calls, but what if you need a solution for your Plain Old Telephone System (POTS)? [Molecular Descriptor] has built a system to invisibly stop landline phones ringing after hours.
The basic principle relies on an analog circuit that detects the AC ringing signal from the phone network, and then switches in an impedance to make the phone company think the phone has been picked up. The circuit is able to operate solely on …read more
Most people hate unsolicited calls, and it’s worse in the dead of night when we’re all trying to sleep. Smartphones are easy to configure to block nuisance calls, but what if you need a solution for your Plain Old Telephone System (POTS)? [Molecular Descriptor] has built a system to invisibly stop landline phones ringing after hours.
The basic principle relies on an analog circuit that detects the AC ringing signal from the phone network, and then switches in an impedance to make the phone company think the phone has been picked up. The circuit is able to operate solely on …read more
