Note
Eico short form catalog 1965, p. 40.
QST, Aug 1967, p. 107.
Allied Radio catalog 1968 (copyright 1967), p. 171.
Kit or wired.
The EICO 753 is a vintage tri-band amateur radio transceiver introduced in 1965. It covers the 80, 40, and 20 meter bands and supports SSB, AM and CW modes.
The 753 uses a filter-type single sideband transmitter and a single-conversion superheterodyne receiver. The transceiver will operate AM, CW, and SSB. The original ad (in the 1965 short form catalog) said the transmitter was "conservatively rated at 180 watts (input power) PEP on all modes." This seems to ignore that fact at PEP applies only to single sideband. In the 1968 catalog, the "conservative" all-mode power rating had been increased to 200 watts PEP. The fine print noted that output power was 110 watts in all modes.
Sidebands are automatically selected. Upper sideband on 20 meters, lower sideband on 80 and 40 meters.
The 753 gained the nickname “Seven Drifty Three” among many users, reflecting the fact that its VFO/oscillator–despite being solid state– never really settled down, no matter how long the rig was left on.
There is no built-in crystal calibrator. While there is an accessory socket for a calibrator, Eico never made one for the 753.
Originally sold for $179.95 in kit form, within a year the price had been reduced to $149.95.
The 753 was probably pulled from production late in 1968 or early 1969, as it does not appear in Eico's 1969 catalog.
The basic points are these:
Solid state VFO
RIT provides ±10 kHz offset tuning
Single knob dual tuning rate: 6:1 and 30:1
Adjustable hairline on tuning scales with cap to prevent accidental movement
High level dynamic ALC
Always-on AGC: "fast attack, slow decay"
Crystal lattice filter
Grid block break-in keying
Product detector of SSB
Triode detector for AM
TR relay has auxiliary contacts for use with an amplifier
PTT and VOX
General specifications
Frequency coverage: 3490–4010 kHz, 6990–7310 kHz, 13890–14410 kHz
Input power: 200 watts on all modes
Output power: 110 watts on all modes
Output impedance: 40–80Ω
Frequency stability (claimed): 400 Hz "after warm up"
Selectivity: 2.7 kHz at 6 db down (no CW filter option)
Sensitivity: 1 µV for 10 db S/N ratio
Audio output: 2 watts, 3.2Ω
Power requirements: 750 VDC @ 300 mA; 250 VDC @ 170 mA; –100 VDC @ 5 mA; 12.6 VAC @ 3,8 amps (all can be supplied by the Eico 751 speaker/power supply, or the 752 mobile supply)
Tubes (16 total): (2) 12AX7, (1) 7360, (2) 7199, (4) 6BA6, (1) 6AQ5, (1) 6BE6, (1) 12AZ7, (1) 12BY7, (6DQ6B), (1) 0B2
Solid State: (2) 2N2926
References
Eico catalog 1968, p. 12.
Eico 753 instruction manual
Brief description. Electronics World, Noc 1965, p. 99–100.
