Instruction/ maintenance manual of the product FR146 Ramsey Electronics
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2 METER FM RECEIVER KIT Ramsey Electronics Model No. FR146 Keep an ear on the loca l repeater action f rom 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 th e 136 to 175 MHz band.
FR146 • 2 P ARTIAL LIST OF AVAIL ABLE KITS RA M SEY TRA NSMIT TER KI TS • FM10 A FM Stereo Tr ansmitter • FM100B Pr ofessional FM Transmi tter • FM25B S yn thesiz ed FM Stereo Transmi tter •.
FR146 • 3 FR146 2 METER FM RECEIVER KIT Ramsey Publication No. MFR146 Price $5.00 TABLE OF CONTENTS I ntroduc tion to the FR 146 ... ........... 4 Circ uit Descr iption ....... .................. 5 Parts List ....................... ................
FR146 • 4 INTR ODU C TION TO TH E FR 146 FM REC EI VER Most Ramsey kits can be classified as “Skill Level 1”. That means that our kits are intended to be sucessful for first-time kit builders. This FR146 FM Receiver is best regarded as a “Skill Leve l 2” project (or at least Level 1.
FR146 • 5 Use bright lighting. A magnifying lamp or bench-style magnifier may be helpful. Do your work in stages, taking breaks to check your work.
FR146 • 6 PA RTS LI ST Inductors 2 small 1 1/2 turn coils (L1,L2) 1 slug-tuned 3 1/2 turn coil [orange color] (L3) 1 shield ed transf ormer coil [marked LB 53303] (L4) Semiconductors and.
FR146 • 7 3 4.7 or 10 uF el ectroly tic ( C15,30,36) 4 100 to 220 uF electrolytic (C14,32,33,35) Controls and Hardware 1 Printed circuit board 3 10K ohm potentio meter (R1,R2,R3) .
FR146 • 8 U2, 3359 FR146 BLOCK DIAGRAM U1 SA602 MIXER.
FR146 • 9 FR146 PARTS LAYOUT DIAGRA M.
FR146 • 10 RAMSEY “Learn-As-You-Build” KIT ASSEMBLY: We have a twofold "strategy" for the orde r of the following kit assembly steps. First, we install parts in p hysical relationship t o ea ch other, so there's m inima l chance of inserting w ires into w rong holes.
FR146 • 11 FURTHER COMPONENT INSTALLATION All "directions" on the PC board (ie: righ t, left, above, below and so forth) assume orientation of your board as shown in the parts layout diagram. Theref ore th e rear of t he board ( conne ctors) is the lower end, and the front (controls) is the upper end.
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FR146 • 14 dot, or notch. Before soldering, make su re that the IC or sock et is perfec tly fflat against the top of the PC board. Install U1, the SA602, in accord with the preceding directions. ❒ 19. Install FL1, th e ceramic filter. This component looks like a capacitor with 3 leads and may be installed either way.
FR146 • 15 PROGRESS SUMMARY So far, you have wire d t he tuned input from the antenna, the RF preamplifier, and the SA602 mixer- oscillator, including the vara ctor tuning circuit. The work you have done has actually formed a simple receiver capable of tuning in VHF signals of all kinds and converting them to a low-level 10.
FR146 • 16 4. MC3359 FM IC and A SSOCIATED COMPONE NTS ❒ 55. Install R17, 10K ohms [brow n-black -orange] ❒ 56. Install R14, 33K ohms [ora nge-orange-orange] ❒ 57. Install C24, .001 uF [m arked .001 , 102, or 1 nF]. ❒ 58. Install C25, .001 uF [m arked .
FR146 • 17 ❒ 73. Install R16, 100K ohms [brown-black-yellow]. ❒ 74. Install R15, 470K ohms [yellow-violet-yellow]. 5. FINAL CONNECTIONS: THE LM 386 AUDIO IC STAGE You now have a wo rking FM receiver ready for adjustment. The output of the MC3359 FM IC simply needs to be boosted to listening level.
FR146 • 18 TESTIN G, ALIG NMEN T A ND AD JUSTMENT To prepare the FR146 FM VHF Receiver for reliable monitoring operation, y ou will need these basic tools: ❒ 1. A usef ul VHF sign al source. ❒ 2. Hexagonal, non-met allic coil slug alignment tool f or L3.
FR146 • 19 Further alignment now consists of adjusting the oscillator coil L3 to permit the tuning control (R1) to cover the 5 MHz . segm ent betw een 135 and 175 MHz of primary interest to you. Assuming y ou wish to adjust for the Two Meter 144-148 MHz Amateur Band, adjus t L3 until you hear your i ntended test signal .
FR146 • 20 Locating the LED immediately above the on-off switch is logical and ideal. The simplest way to make a good installation is to drill a neat hole ju st slightly smaller than the diameter of the LED. Then, en large the hole a little bit at a time just enough to let the LED be pressed in and held firmly .
FR146 • 21 FR146 TROUBLESHOO TING HINTS Ramsey FR-series FM receivers are among our most widely-used and popular kits. The circuit itself, assembly and us e are "cut-and-dried." If y our receiver does not work, there is probabl y either an error in assem bly or a def ective part.
FR146 • 22 hearing about significant performance i mprovements, we do no t recom mend casual modification attempts. Howeve r, there is one practical custom ization which could be un dertak en by exp.
FR146 • 23 The Ramsey Kit Warranty Ple ase read caref ully B EFORE ca lling or writ ing in abou t your k it. Most prob lems can be solv ed w ithout contac ting the f acto ry. Notice that thi s is not a "fine print" warranty . W e w ant you to u nders tand your righ ts and ours too ! All Ramsey kits w ill work if assemble d properly.
R146 • 24 FR146 2 Meter FM Receiver Kit Quick Refer ence Page Guide I ntrodu ction to th e FR146 .......... ..... 4 Circ uit Descr iption ....... ................... 5 Parts List ................................... ..... 6 Simplified Block Diagram .
An important point after buying a device Ramsey Electronics FR146 (or even before the purchase) is to read its user manual. We should do this for several simple reasons:
If you have not bought Ramsey Electronics FR146 yet, this is a good time to familiarize yourself with the basic data on the product. First of all view first pages of the manual, you can find above. You should find there the most important technical data Ramsey Electronics FR146 - thus you can check whether the hardware meets your expectations. When delving into next pages of the user manual, Ramsey Electronics FR146 you will learn all the available features of the product, as well as information on its operation. The information that you get Ramsey Electronics FR146 will certainly help you make a decision on the purchase.
If you already are a holder of Ramsey Electronics FR146, but have not read the manual yet, you should do it for the reasons described above. You will learn then if you properly used the available features, and whether you have not made any mistakes, which can shorten the lifetime Ramsey Electronics FR146.
However, one of the most important roles played by the user manual is to help in solving problems with Ramsey Electronics FR146. Almost always you will find there Troubleshooting, which are the most frequently occurring failures and malfunctions of the device Ramsey Electronics FR146 along with tips on how to solve them. Even if you fail to solve the problem, the manual will show you a further procedure – contact to the customer service center or the nearest service center
