LI-30T #34 closewound on ceramic form.
L2—1ST #28 closewound on Ya" form. 2T link of hookup wire.
XI —HC6/U xtal (fundamental), A 13.715 mhz crystal covers approx, 50.1 00 to 50,145 mhz.
often be salvaged from the high voitage "cage" of older style TV receivers. Extensions to t he front panel for the mixer, driver and final amplifier controls were made from % inch brass tubing. Short lengths of tight-fitting rubber tubing were used to couple the extensions to the capacitor shafts.
There are two small subassemblies used in the construction. Tlie bridge rectifier diodes are assembled on a phenolic board which is bolted vertically underneath the chassis. Small holes are drilled in the board: the leads of adjacent diodes are placed through a liole, bent over, clipped, and then soldered together. If desired, 270 K resistors and .002 disk ceramics may be paralleled with the diodes to give voltage equalization and tran sient protection. The components associated with the rf output meter are mounted on a terminal strip which is bolted inside the 2E26 compartment near the antenna jack. A shielded lead carries the rectified voltage to the meter on the panel.
The 41.1 MHz injection is supplied by a VXO assembly built on a small plate and mounted above the main chassis. Certain of the VXO components such as the crystal socket and tuning capacitor are mounted % to Vi inch from the p>ate to minimize capacitance to ground.
The usual VHP wiring techniques must be observed in order to produce stable TVHFree operation. All filament leads should be shielded and .001 disk ceramics should be placed from the iiot filament lead to ground at each tube socket. In the higher frequency ri' stages, lead length should be kept short. Grounding should be done as directly as possible and it is desirable to have only one or two common ground points for each stage. All plate voltage leads to the mixer, driver, and final, are routed through the main partition with feed-through capacitors.
The 10,7 MHz //transformers used in the 6AU6 amplifier, are an older style of transformer using slug-tuned windings. They are more easily adapted than the smaller "K-fran" type. In T] the primary winding was removed and replaced with a 3 turn link. The secondary of Tj is moved down to 9 MHz by the addition of a mica capacitor. In
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