QT1LJ Lost members! Where are you!
IoAR HQ needs the updated, correct address of the following;
Davis, RAW KB6CS Livingstone, A.W. K6VYJ MacArthur, Roger K9UYA Miller, Chase. W. Jr+ W4AXV Nelson, Robt. L. K6ZCQ
Keep the news clips coming!
The response to HQ's appeal for news clippings concerning amateur radio has been excellent! Here is a project in which everyone can help! Watch > our newspapers and magazines for any references to amateur radio, cut out the clips and send them to HQ. Please help fill HQ's Scrapbook!
With the ratification of the C and BL contained in the January 1966 Members Report tins became an official document of IoAR. Members are urged to keep the January Report on file. The C and BL contain many pertinent facts about IoAR structure.
The Membership Department has been requested lo include copies with all membership processing since Feb. 5f 1966,
Members who have not yet received their copy, please advise IoAR HQ,
Hank Olson W6GXN 3780 Star King Orele Palo Alto, Californio
The Solid-State Product Detector
Increasingly, the use of solid-state circuitry is taking over in the field of electronics.
In amateur radio equipment, too, the "little three-legged gadgets" (transistors) are making in-rouds. That solid-state ham gear has 'arrived/ is evidenced by several of the new SSB transceivers on the market, which use tubes only in the transmitter output stages.
There remain, however, a number of areas in commonly-used amateur circuitry, where transistors are awkward to use. For this reason, I suppose we shall continue to see new ' all-tube" designs lor some time to come. If a manufacturer decides on a tube-transistor "hybrid" circuit, he must face having two power-supplies; a high-voltage* low-current supply for tubes and a low-voltage, high-current supply for transistors. The expense of having two supplies for a "hybrid" design makes the two-faction system a near-reality—a company usually decides to either manufacture "all-tube" or all-solid state/ This means that every circuit block must be made solid-state (at least in the low power stages) before a manufacturer can seriously decide to join the "solidstate camp/*
One of these "hard-to transistorize1 blocks in our circuitry is the product detector, as needed for SSB reception. One obvious solidstate solution is the diode-ring demodulator, as used by Bell Telephone Laboratories, w hen
SSB was first put into commercial service. The ring-demodulator is shown in Fig, 1, Of course, nowadays one would use a matched-quad nf modern silicon-diodes instead of I he original copper-oxide quad. The trouble with the ring-demodulator is that it requires diode-matching and a special balanced input system to be used, Also, a relatively large power level from the liFO is required to drive the ring, as the BFO current must drive the diodes of the ring well into forward conduction.
; here are several double-diode prod net-detectors in amateur use, which are simpler to use than the full-blown four-diode ring-demodulator, but these are basicallv of the same family*1*2*3
Another amateur solid-state product detector is similar to the popular triode-tube
Fig. 2A. Triode tube product detector.
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