Frederick Plantronics Model 1273 FSK Teletype Keyer no 2/ Demodulator Nice Unit

Description: Description Corrected 09/22/2021 - A copy of the Plantronics/Fredericks Manual on CD comes with this set. For Sale: A Frederick / Plantronic Model 1273/S1 FSK Teletype Keyer - Demodulator is set for a single shift. Typically they have a frequency shift of 850kHZ and looks at baud rates of 75 or 600. Shift frequency is determined by two crystals labeled Mark & Space on the Tone Keyer board inside the unit. The installed crystals are Mark 2182.5 kHZ and Space 1417.5 kHZ. The I/O lines are attached from the rear and there is a switch to toggle I/O to coax (75 ohm) or open lead (600 ohm). Construction is mil spec: G10 boards with protective coating. Power supply appears good as unit powers up and all fuses are good. The 1273 is a single shift unit so far as I can tell, designed for dedicated "slave" service. Examples of possible application include ITTY, ham radio narrow shift, or dedicated and secure between office data connection for a business. Unit measures 2" high and 19" by 19" in size. For ham use, recrystallize using 2125 kHZ for the MARK frequency (for both 170 & 850 shifts) and use 2295 kHZ and 2975 kHZ for SPACE respectively. Should be a lot of fun for the right person. Condition: Excellent physical condtion. Unit powers up fine. Keyer output level still set and responds when selected. We have no way to further test this unit. An experienced teletype person should be successful recrystallizing the unit to amateur radio preferences. Re-purposing this involves changing the upper & lower shift point crystals and adjusting, to what extent possible, the baud rate. Terms: Sold as described but strictly as is. We do not accept returns as we are downsizing and not retailing. Shipping: We are estimating the single shipping. Teletype Enthusiasts: The best way to support the teletype interests of amateur radio is to put a RTTY or AFSK or FSK signal on the air. It does not matter if anyone comes back to you right away it only matters that signals start populating the teletype areas. Get other amateurs used to hearing teletype as well as honoring the traditional teletype spaces. Use prearranged schedules to QSO with other teletype stations when you can. Eventually the mode will begin getting some use. If you need transmitting equipment to do this, I have several vintage tube based units that will work fine. You know the rule: use it or lose it. Let's not let it die without an effort to keep the real machines on the air.

Price: 179.95 USD

Location: Baton Rouge, Louisiana

End Time: 2024-08-11T18:11:19.000Z

Shipping Cost: N/A USD