International Crystal

Since I have been building some kind of solid-stale unit such as an i-f amplifier, an rf power stage, a solid-state X-band oscillator, etc., at an average of about one a week, I appreciate an organization that is marketing kits for us amateurs in a sensible fashion. Frankly the prices don't appear sensible, being much, much too low! For $2,95 you get a complete crystal oscillator kit (3 60 MHz). You doni get the crystal at

Oscillator Radio



that price, but you do get the transistor, and the oscillator works right off the bat.

You can follow the oscillator with an rf power amplifier for $3.75 that puts out 200 mW up to 30 MHz and will light a pilot lamp brightly. Any time you can light a bulb you can have QSOs. With a 201 A and 90 volts of B battery I used to work all up and down the East Coast every night. Of course ! was in Bermuda, parked just outside the American band, and it was 1925. Vll bet it can still be done today.

The nice thing with these kits is that you can put them on the front seat, either with dry cells or the ear battery and drive up on any hill, put a small beam on top of the car, and away you go. Don't just go up there with a halo or a whip, please! Try something with a tittle more sock to it. Battery operation plus a hill plus VH! equals DX.

1 Frequency Range

3. DC Power Required

4. Frequency Tolerance with OX and EX Crystal,

5 Operating Temperature Range 6. Frequency Change with 1 VoU Supply Change

7 Output Levef Change with 1 Volt Supply Change

9 Mounlmg

Complete Kit (less crystal)

LO—3000 KHz to 19999 KHz HI — 20000 KHz to 60000 KHz 2 voîls rrns into 50 ohms (min) 6 volts at 20 ma (operates 4 to 9 volts)

0 io 50 Degrees Centigrade

x lVa" * HV 4 tholes with spacers or fits Oiver 1 Va" chassis hole

Fig. 1. OX oscillator kit specs.

International Crystal Oscillator


You probably know by now that my fun begins on six meters arid goes on up, so l1m mostly talking 50 MHz to start with. If I did try one of those little rigs on 40 or 20 who knows what I could work ?

The OX Oscillator Kit.

There is a certain fascination about these little kits that grows on you. It could be due to the absence of cerebration needed, something like a vacation for tire, as most of the work I do on this well-worn bench does require at least a little.

When you get the kits you receive a four-page instruction folder with good, simple dope and the circuit. You also get a very neat little copper-clad phenolic board which not oniy has the actual circuit on the copper side, but clear and well-printed names of the components on the other side, ft is almost impossible to go wrong. I did. If I had read every word on that little four-page sheet I would have been fine, but I hurried a little too much, rhere is a just slightly tricky spot it you don't read it all over carefully. This is where it says on page 2, "the remaining parts {R, iand C) are selected according to the frequency range from the chart below/" What they mean is that this particular selection is done at the parts packing stage in Oklahoma City. And il was done exactly right for the "OX-HP kit I ordered. Just read every word and think it out with the aid of the board and the schematic and you won't go wrong. Also cheek aQ the parts in the bag, recheck with the circuit on page 4, and you'll have it correct the first time.

Be sure of this, because it is not handy to replace or change parts that are soldered in place. Plan to do any experimentation outside the board.

As soon as I got those little parts "selected according to frequency"" installed (my fault entirely on that one) and threw the battery switch, bingo, 3V dc output on the meter of my trusty old 25 to 75 MHz tuned diode receiver-rf meter.

One actual omission in the instructions did show up. Tve just read everything over again once more to be sure this one wasn't my fault also. Several loose connections showed up as intermittent oscillation, and these were in "the connector pins that have been staked into the board a I the factory" department. As soon as I soldered them onto the copper circuit, operation was steady as a rock and has been since then.

The instructions are pruned down to exactly the minimum possible number of words and still get the correct ideas over. The exact quantity of all the parts needed, including "l jumper wire, No. 24, 1 % in/*

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