Multi-Elmac

1.1 GENERAL. THE MULTI-ELMAC AF-67 Trans-Citer is a ten-tube variable frequency or crystal controlled seven band transmitter or exciter. All circuits are simultaneously switched to the desired band by a single bandswitch lever.

Designed as a complete transmitter for mobile or fixed installations, or an exciter to drive a higher power transmitter. When used as an exciter the 500 ohm tap on modulation transformer can be used to drive the higher power modulators.

1.2 DIMENSIONS. The maximum external dimensions of the AF-67 Trans-citer, excluding projections of control knobs, is 11 1/4 inches wide, 7 inches high, and 8 1/2 inches deep behind panel. Approximate weight is 18 pounds.

1.3 CIRCUIT DESCRIPTION. The AF-67 Trans-citer employs a variable frequency oscillator with output on wither 1.75 to 2.0 Mc. or 3.5 to 4.0 Mc. In addition to the V.F.O. feature, two crystal positions are included for operation on two spot frequencies. Any crystal that will work straight through, double of quadruple to the desired frequency may be used. The oscillator circuit employs a voltage regulator tube to maintain the plate voltage at a constant level.

The multiplier stages are broad tuned with a front panel control for peaking the final grid, insuring best performance on all bands. The audio circuit is designed to use either a carbon microphone or a low output microphone such as a crystal or dynamic. A slide switch on the rear apron on the AF-67 Trans-citer sets up the circuit for use with either type of microphone. A reactance tube modulator is incorporated in the variable frequency oscillator circuit for narrow-band-frequency-modulation. The variable frequency oscillator dial scale is directly calibrated in megacycles for each of the amateur bands.

1.4 TUBE COMPLIMENT. The AF-67 Trans-citer is supplied complete with all tubes, tested in the individual unit, as follows:

6AK6	Oscillator
6BJ6	Reactance Modulator
6AG5	Buffer-multiplier
6AQ5	RF Driver
6146	Final RF Amplifier
6AU6	Speech amplifier
12AU7	AF Driver
5881 (2)	PP Modulators
OB2	Voltage regulator
#44 (2)	Pilot Bulbs

1.5 OUTPUT. The AF-67 Trans-citer is designed for use with a resonant antenna coupled to its output with a transmission line of 50 to 300 ohms impedance. Other impedance or balanced lines can be coupled through the use of an antenna tuning device. When used as an exciter the coupling link of the high powered final can be directly connected to the AF-67 with a suitable length of coaxial cable. The MULTI-ELMAC AF-67 is designed for a maximum plate power input of 60 (sixty) watts. Maximum ratings for this Trans-citer are 600 volts at 100 milliamperes; or 500 volts at 120 milliamperes. Full 100% modulation occurs when the modulator plate current swings to about 60% of the final plate current with normal voice frequencies.

1.6 AUDIO. The modulation transformer is provided with a 500 ohm output tap brought to the power plug for driving the grids of high powered modulators. The 5881's will deliver approximately 40 watts of audio with a plate supply of 500 volts.

1.7 POWER SUPPLY. The AF-67 Trans-citer was intentionally designed to use an external power supply in order to permit (a) use of PMR-6A receiver power supply to supply the low level stages, (b) use of the AF-67 Trans-citer with an AC operated power supply at a fixed or portable location, (c) use of a dynamotor or vibrator supply in mobile installations, or (d) use of the Trans-citer as a driver-exciter for high powered transmitters. A suitable MULTI-ELMAC power supply MODEL PS-2V for portable or fixed station operation from 115 volt AC lines is available.

1.8 POWER CONNECTOR. A 15 prong female connector is provided with each unit. The 15 prong connector allows all circuits to be arranged for maximum flexibility. Making it possible to use the AF-67 Trans-citer in various types of installations.

1.9 ACCESSORIES. The following accessories are available for use with the AF-67 Trans-citer:

Designed to be used with the Elmac AF-67 Trans-Citer or a variety of other applications.

CFS-1 Cable Complete cable, plug, and fanning strip to connect the PS-2V to the AF-67 Trans-citer.

PTR-1 Kit. Includes rectifier, relay and filter condenser to allow "Push-to-talk" operation of your station from an AC supply.

1.1 GENERAL. The MULTI-ELMAC PMR-7 RADIO RECEIVER is a ten tube double conversion superheterodyne covering the 160, 80, 40, 20, 15, and 10 meter amateur bands, plus the standard broadcast band. Designed primarily as an efficient communications receiver for mobile use, it is also especially suitable, because of its small size, for (1) marine and aircraft installations; (2) portable operation; and (3) as a fixed station or monitoring receiver. It is not intended as a converter to accessory to another unit, but a complete receiver, employing a separate power supply and speaker as described in this manual. Every effort has been made to furnish the user with an extremely stable receiver of rugged construction, compact layout, and high sensitivity.

1.2 DIMENSIONS. The maximum external dimensions of the PMR-7 receiver, including the control knobs are: height 4 5/8", width, 7", and depth, 11 1/2". The depth behind the panel is 9 7/8". The net weight of the receiver is 8 1/2 pounds.

The ESS-3 "S" Meter is an accessory external 0 - 1 milliampere meter calibrated in "S" units for use with the Multi-Elmac PMR-7 receivers.

Issue	Page	Title	Author
Oct 1958 QST	75	Modifications to the Elmac AF67	Stewart, Harry - W8PSV (now AA4IB)
Jul 1960 QST	60	Multi-Elmac M1070 Power-Supply Notes (Hints and Kinks)	Stewart, Harry, W8PSV (now AA4IB)
Feb 1991 ER	27	Elmac AF-67 Audio Mod	Seaman
April 1991 ER	28	Elmac AF-67 Modulator Fix	Winfield
Jul 1992 ER	14	The Multi-Elmac Company	Salter
May 1994 ER	20	Multi-Elmac Co., Follow up to in ER #39	Goldstone
April 1999 ER	12	The Elmac AF-67 Trans-Citer	Jim Hanlon, W8KGI
May 1999 ER	12	The Elmac AF-68 Trans-Citer	Jim Hanlon, W8KGI


AF-54	AF-67	AF-68

AF-54	AF-68	AF-68


PRM-6A	PMR-7	PMR-7 w/S-meter	PMR-8


AF-67	PMR-7


1955 Multi-Products We Have Moved Ad	1955 Multi-Elmac PMR-7 Ad	1958 Allied Radio Ad	1959 Multi-Products Ad	1957 Allied Radio Catalog

Wednesday Nights at 7:00 P.M. C.S.T., 3.880 MHz (except for first Wednesday of month).