Look at this 1980s Radio Shack phone

Look at it! Years before translucent iMacs became a thing, Radio Shack sold a series of clear landline phones, including this number…


100% through-hole components and an actual, physical, ringing bell. This one also had incandescent bulbs in the handset and base that would flash when the phone rings (a later model used neon tubes).


The “P / T” switch selected between pulse and tone dial modes, as a few phone exchanges still couldn’t handle this newfangled tone dialing thing.

The electronics are almost entirely discrete, with ONE single IC chip in the handset:


…a UM91210 Tone/Pulse dialer with redial memory. “UM,” by the way, stood for Unicorn Microelectronics. For reals. I am not making this up.

“Speed dial” in those days consisted of a small slip of paper on which frequently-used numbers could be written:


But my favorite detail of this phone…it’s most distinctive, most “period” attribute, even moreso than a cord or bell…is a subtle thing right here:


Prior to an anti-monopoly ruling in 1968, buying a home telephone was not an option…all equipment was rented from AT&T. To minimize returns and service calls, their gear was incredibly overbuilt, indestructible…and heavy. The new third-party telephones were less durable and less expensive…but to mimic the familiar heft of classic phones, it was common to have idle weight bolted in both the handset and base. This pattern persisted for years until cordless phones and lightweight office handsets became a familiar norm.

Old electronic equipment is sometimes derisively referred to as a “boat anchor.” These vintage phones literally incorporated anchors as a feature.

Adafruit publishes a wide range of writing and video content, including interviews and reporting on the maker market and the wider technology world. Our standards page is intended as a guide to best practices that Adafruit uses, as well as an outline of the ethical standards Adafruit aspires to. While Adafruit is not an independent journalistic institution, Adafruit strives to be a fair, informative, and positive voice within the community – check it out here: adafruit.com/editorialstandards

Join Adafruit on Mastodon

Adafruit is on Mastodon, join in! adafruit.com/mastodon

Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.

Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7pm ET! To join, head over to YouTube and check out the show’s live chat – we’ll post the link there.

Join us every Wednesday night at 8pm ET for Ask an Engineer!

Join over 36,000+ makers on Adafruit’s Discord channels and be part of the community! http://adafru.it/discord

CircuitPython – The easiest way to program microcontrollers – CircuitPython.org

Maker Business — “Packaging” chips in the US

Wearables — Enclosures help fight body humidity in costumes

Electronics — Transformers: More than meets the eye!

Python for Microcontrollers — Python on Microcontrollers Newsletter: Silicon Labs introduces CircuitPython support, and more! #CircuitPython #Python #micropython @ThePSF @Raspberry_Pi

Adafruit IoT Monthly — Guardian Robot, Weather-wise Umbrella Stand, and more!

Microsoft MakeCode — MakeCode Thank You!

EYE on NPI — Maxim’s Himalaya uSLIC Step-Down Power Module #EyeOnNPI @maximintegrated @digikey

New Products – Adafruit Industries – Makers, hackers, artists, designers and engineers! — #NewProds 7/19/23 Feat. Adafruit Matrix Portal S3 CircuitPython Powered Internet Display!

Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at AdafruitDaily.com !


  1. More interesting is what tech was “high tech” when this was a thing (I remember being tiny and wanting this EXACT phone from the catalog!)

    This was around the time that services started becoming more digital. I live in CT, and we always had our own independent phone company, one of the few that remained always away from Ma Bell– SNETCO. They were quite quick in moving to digital switching, and processor controlled IO. Around the late 80’s they came out with a service called TotalPhone.

    It was based around the button to the right of the p/t switch, labelled reset. What it did was disconnect the tip (tip top, ring red right) for a specified number of milliseconds based on the circuit. Apparently it was standardized enough that SNETCO could detect the disconnect and instead of disconnecting the call, could do things *impossible* until then on a single line, like put the call on hold, let you call someone else, and upon hitting the reset button again, conference the two together–for $5 a month.

    At least, this is how I remember that button, it may have been later that it was standardized. But still. I’m only 34–today is my birthday–and this pops up on feedly.

  2. The phone company also used to charge extra for touch-tone dialling. My parents wouldn’t spring for it even after we had a push-button phone in the house, so you could hear the phone simulate the switchhook clicks of a rotary phone every time you dialled.

Sorry, the comment form is closed at this time.