Circuit Details - Second Mixer
before building this section.
Circuit Details - Crystal Oscillator/Amplifier
before building this section.
To get the best print of the above picture, right click the mouse on the image, select "View Image". In the new browser window, click print, set layout to "Landscape", then "OK" to print.
If you are going to use the 7 digit LED frequency counter with the receiver, there is a crystal oscillator modification that can be done at this time. Please see "Crystal Oscillator Modification" for information. This modification is done when you do the Crystal Oscillator Switching, Crystals, and Phototransistor section.
____Mount spacers on each side of the board on the four corners to provide support for insertion of parts and easy soldering. Picture
Insert all the components that have their values inside the footprint. They are the following:
____15 - .01 capacitors (Bag 3)
Solder____6 - 100 ohm resistors (brown, black, brown) (Bag 3)
____5 - 100K resistors (brown, black, yellow) (Bag 3)
____3 - 470 ohm (Bag 4), All located inside the second mixer.
Capacitors (Going left to right on the board):
____1 - 39pf NPO (Bag 4), Located to the right side of the MOSFET in the Amplifier. Small, blue colored, short leads, labeled "390J, 201".
____5 - LEDs (Bag 3), Red colored, match the flat on the LED to the flat on the footprint. The short lead is on the same side as the flat.
Crystal Oscillator Switching, Crystals, and Phototransistor
____1 - Phototransistor (Bag 5), transistor looking part with three leads and a glass face, the "B" pin is not connected to any traces and can be soldered after the device has been aimed at the IR LED, if desired (not necessary).
If you are using the LED Frequency Counter, this part is mounted with a 56K resistor, see "Crystal Oscillator Modification" for instructions. Also change the .01 (shown in picture above the phototransistor) to a 47mfd electrolytic, as noted in the modifications.
The phototransistor aims at the IR LED near the outside of Board 1 at the 4.000 MHz crystal filter. Note the location of the tab when mounted underneath the board. This is done when the boards are stacked as shown on the home page. Picture
Solder____1 - 3.457MHz crystal (Bag 4), Has a gray plastic cover over the crystal with the markings "NYMPH C O 17915-03".
____1 - 4.000MHz crystal (Bag 4), The markings are "4000 KSS 2FT".
Solder____3 - MOSFETS (Bag 2), (Picture) static sensitive part, touch a ground wire before taking it out of the bag, notice the dot on MOSFET (may be difficult to see, hold at an angle to a light source and you can see the shadow of the dot), the dot is located to the left of the second line of the text on the MOSFET. A dot is placed outside the footprint so that you can double check your placement after it has been soldered to the PCB. The leads on each side of the part need to spread apart slightly to fit the footprint.
____Check the dot on the MOSFETs and the Minicircuits transformers.
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