[Boatanchors] FS: MULTI-ELMAC AF67 Transmitter AM-CW

Bry Carling bcarling at cfl.rr.com
Sat Feb 16 13:37:24 EST 2013

FOR SALE:  Multi-Elmac 60 Watts AM-CW, TUBE TRANSMITTER, Model 

THE MULTI-ELMAC  AF-67 Trans-Citer is a ten-tube variable 
frequency or crystal controlled seven band transmitter or 
exciter.  It uses a really good "push-pull" plate modulation 
scheme with two 5881 modulator tubes. 

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.  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. The AF-67 Trans-citer is supplied complete with 
all tubes, viz: 6AK6 Oscillator,  6BJ6 Reactance Modulator,  
6AG5 Buffer-multiplier,  6AQ5 RF Driver, 6146 Final RF 
Amplifier, 6AU6 Speech amplifier, 12AU7 AF Driver, Two 5881 PP 
Modulators,  OB2 Voltage regulator

The AF-67 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 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.

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.

Dimensions:  11 1/4 inches wide, 7 inches high, and 8 1/2 
inches deep.
Weight:  18 pounds.

There are some good articles on maintaining and modifying the 
AF67 at some web sites. This one is unmodified as far as I 
know. Fairly good condition for its age, and is complete, with 
all original knobs etc.

One of these sold recently on eBay for $181.00

Will sell for only $99.00 plus shipping. Or next stop eBay.

Picture and details at:


73 - Bry, AF4K

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