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Fig. 6. Full size P.C. board for 100 wait amplifier.

New Products continued capacitors are very easy to get to, by (he way. We say that in memory of an earlier rig or two where you had one hell of a time getting your crystals on channel.

The front panel is right up to date —black with green back lighting on the channel switch and meter. There is a linle light that comes on when the squelch Operates and we suspect that not .a few amateurs will be using this for an emergency carrier operated relay. This rig looks as if it could be converted into a repeater

tOO IVatf solid slate linear amplifier tremely low load impedance they require over the full range of 1.5 to 30 MHz. Thus they are more suited to limited bandwidth applications. The four PT5741's used here require a slightly higher load impedance than the PT5742's which makes broad banding the circuit a bit easier. The 100 watt amplifier in Fig. 5 is essentially two 50 watt push-pull amplifiers that are fed in phase with each other through T1. Each output is combined in T8 and 100 watts overall is fed into the antenna. Any ampli-iude or phase unbalance is absorbed by R6 and R7.

This, amplifier is designed to be driven by the 25 watt amplifier running class A. A siight bias adjustment will do this and the powar falls to 5 :lean watts which is the proper amount to drive the 100 watt amplifier to full output.

These two amplifiers are perfect for an all-band all solid state rig. They could both be incorporated into a small transceiver, or the higher power amplifier could be left forever in the trunk of your car to be powered by the miniature 25 wan rig that you store away in the glove compartment.

The two PT5740's and 30 ferrite beads needed to construct the 25 watt amplifier are available for $36,00 as Kit #PKT 3104 and the four PT5741's and 84 ferrite beads for the 100 watt amplifier are available for $112.00 as Kit #PKT 3103, from Ham Radio Center, $342 Oiive Blvd., St. Louis MO 63132.

very easily. The modules are all separate and relatively well shielded from each other.

We set one unit up on top of nearby 73 mountain and drove around with the other in the Rover, with a trunk mount Hustler 220 antenna (5/8 wave, of course). Frankly we couldn't see much difference in the coverage between the 220 rig and a ten wan 146 MHz rig. They both held up about the same and started falling off about the same. There seemed to be a few more hot spots where the 220 rig would peak up than on 146 once we were in a shadow area, but the difference wasn't remarkable.

The price is not firm on this new rig yet, but it is expected to run under £350. It would make a fantastic package at that price,

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