Note
QST, May 1965, p. 147.
QST, Aug 1965, p. 102.
CQ, Apr 1967, p. 37.
QST, May 1968, p. 135.
Allied Radio catalog 1969 (copyright 1968), p.203 (TR-4B) (is this error?)
QST, May 1970, back cover.
QST, Nov 1972, p. 127. 1972–1977 (TR-4C) $599.95
QST, Dec 1975, p. 149. (some details)
QST, Mar 1976, p. 113.
QST, Feb 1977, p. 157 (TR-4Cw, admitting that it is old, but...)
QST, Mar 1977, p. 93.
QST, Dec 1977, p. 155. (now with RIT)
On the TR-4 series’ 13th birthday, Drake made it more CW friendly. A 500 Hz CW filter was added. It and the existing sideband filter could be selected independent of mode.
Later that same year Drake added receiver incremental tuning (RIT) to the TR-4Cw. To do this, the noise blander control was replaced by the RIT control. Control of the noise blanker was moved to a push button added beneath the RF Tune control, together with another added button to turn RIT on and off. RIT provides approximately ±3 kHz of offset.
⚠️ Note that these tubes were changed.
V11 changed from 12BA6 in the "C" to 6BZ6 in the "CW"
V19 changed from 6EV6 in the "C" to 6FQ7 in the "CW"
In most other respects the CW and CW/RIT are same as the TR-4.
