User manual RAMSEY FR146

[. . . ] 2 METER FM RECEIVER KIT Ramsey Electronics Model No. FR146 Keep an ear on the local repeater action from your easy chair with this simple and fun to build FM receiver. Tune the entire 2 Meter band or the VHF high Police and Fire band. · · · · · · · · · Tunes any 5 MHz portion of the 136 to 175 MHz band. Excellent performance, less than 1 uV sensitivity. [. . . ] Install C27, 1 uF electrolytic, observe correct polarity. Install D2, the 1N4148 signal diode, observe correct orientation of the banded cathode end. Be sure you correctly identified D2 and did not confuse it with the varactor diode already installed. FR146 · 16 73. Install R16, 100K ohms [brown-black-yellow]. Install R15, 470K ohms [yellow-violet-yellow]. 5. FINAL CONNECTIONS: THE LM386 AUDIO IC STAGE You now have a working FM receiver ready for adjustment. The output of the MC3359 FM IC simply needs to be boosted to listening level. A few more connections, and your receiver will be ready for adjustment and testing!Now would be a good time to review some of your previous work and also to make sure you have on hand what you'll need for testing: antenna, fresh battery, earphone or speaker with correct plug or adapter. Review the instructions for installing U1 and U2. Insert the LM386 IC (U3) with the band or dot oriented correctly. Install C32, a 100 to 220 uF electrolytic, observe correct polarity. Install C31, . 01 uF (marked . 01, 103, or 10 nF). Install C36, 4. 7 or 10 uF electrolytic, observe polarity. Install C33, 100 to 220 uF electrolytic, observe polarity. Install the battery snap terminal in the two holes below S1, making sure that the positive (red) lead is inserted into the (+) hole on the PC board. The battery bracket may be attached in a variety of ways. A wire jumper can be passed through the two holes on the PC board, then both ends soldered on the underside of the board. You may prefer to use very small screws or even a double-sided mounting adhesive strip or glue. In using such methods, make sure that the battery will not block the PC board's mounting hole in its vicinity. Wiring of the PC board is now complete. If you have the patience, we suggest a short break. Then take a magnifying lens and a bright light and examine all your solder joints, touching up any connection which appears less than perfect. [. . . ] BE returned in fully-assembled form, not partially assembled. BE accompanied by the proper repair fee. No repair will be undertaken until we have received the MINIMUM repair fee (1/2 hour labor) of $25. 00, or authorization to charge it to your credit card account. INCLUDE a description of the problem and legible return address. [. . . ]