Manuale d’uso / di manutenzione del prodotto FT146 del fabbricante Ramsey Electronics
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FT146 • 1 2 METER FM 5 W A TT TRANSMITTER KIT Ramsey Electronics Model No. FT146 • Dire ct, tr ue FM for excel lent voice and dat a qual it y. • Both Data a nd mi ke audi o inputs • Solid 5 watt RF ou tput - add our PA -146 for 40 watts • Crystal controlled with 146.
FT146 • 2 RAMSE Y TRANSMI TTER KITS • FM10, FM-25 FM Stereo Tr ansmitters • TV6 Tele vision Transmi tter • Cube TV Tra nsmi tt er s RAMS EY RE CEI VER KI TS • FR1 FM Broadcast Receiver • A.
FT146 • 3 FT146 FM RECEIVER KIT Ramsey Publication No. M FT146 Price $5.00 TABLE OF CONTENTS I ntroduc tion to the FT146 .............. 4 Circ uit Desc ription ......................... 5 Parts List ............................. ........... 6 FT146 Asse mbly Instructio ns .
FT146 • 4 INTRO DU CTION Two meter FM has been around for y ears, but never with the popularity that is enjoyed today. In the old da ys, hams snooped around the local tw o-way radio shop in search of an obsolete ta xi cab or police radio.
FT146 • 5 and IC chip) give the equ ivalen t of ab out 130 or more tran sistors an d diodes. And, in addition to 13 inductors, a crystal and the various plus and jacks, there are over 60 capacitors and resistors.
FT146 • 6 into transm it. There is no need to con trol the voltage to any other tran sistor s since they a ll operate class "C". A class C am plifier draws no current unless it is driven, so there is no need to s wit ch the later stag es on and off .
FT146 • 7 Inductors and ferrite co res: ❒ 2 Shielded can tunable inductor (marked 007007) [L9,13] ❒ 2 Tunable indu ctor (pink plastic body ) [L5,11] ❒ 2 6 hole ferrite bead core [L1,6] ❒ 2 S.
FT146 • 8 RAMSEY Learn-As-You-Build KIT ASSEMBLY: There are over 200 solder connections on the F T146 printed circuit board. Th at means your work could be 99% perfect and you could STILL ha ve 2 or 3 cold solder points or so lder bridges.
FT146 • 9 ❒ 3. Install J2, the subminiature phone jack. Solder all three points. Be gentle and patient in inserting, so as not to damage the solder tabs. ❒ 4. Install R13, 5K trimm er pot. This is the modulation adjustment control. ❒ 5. Install U1, LM358 op-a mp IC chip.
FT146 • 10 ❒ 21. Install R15, 10K ohm (brown-black-orange). ❒ 22. Install C33, .001 uf disc capacito r (marked .001, 1 nf or 102). ❒ 23. Insta ll R16, 10K ohm, (br own-black-orang e).
FT146 • 11 ❒ 41. Install R7, 470 ohm (y ellow-violet-brown). ❒ 42. Identify Q1, a 2N3904 N PN transi stor (m arked 2N3904). I nstall Q1 , observing correct placement of the flat side. ❒ 43. Install Q2, anot her 2N39 04 NPN transistor (marked 2N3904).
FT146 • 12 ❒ 60. Install C21, 4.7 or 5 pf disc capacitor (marked 4.7 or 5 or 4.7K or 5K). ❒ 61. Install L9, slug tune d shielded coil (marked 007007). This coil is part of the first tripler section. It is tuned to the third harm onic of t he crystal oscillator.
FT146 • 13 stages of your transmitter. W e recommend that you get them ready for installation before assemb ling the Driver and Final stages. If you prefer to proceed with those stages, winding coils a s you go, that's f ine, too, as long as you realize th at all coil making details are provided in this section.
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FT146 • 16 The "legs" o r leads f or inserting L2 , L7, L3 an d L4 sh ould be abou t " long. These coils should sit about 1/8" maximu m above the PC board w hen soldered. ❒ 80. Install L12, on e of the small 3 turn ferrite bead RF chokes y ou wound.
FT146 • 17 ❒ 97. Install D4, 1N4148 sty le signal diode (glass body with black band). Observe c orrect or ientation of the ba nded end. ❒ 98. Install TP3, the last test point. Se lect a 1K resistor, R29 (bro wn-b lack- red). Trim back one lead w i re to a length of inch.
FT146 • 18 ❒ 112. Install C2, 100 to 220 uf electr olytic capacitor. Be sure to observe polarity - especially with this part since it is directly across th e power supp ly and if reversed, could overheat so fast, so much that it could explode ! ❒ 113.
FT146 • 19 coil drastically whenever it is insert ed into the coil. Y ou may use a metal hex key if you are awar e of this ef f ect and are willing to remove the hex key from the coil after ea ch adjustment. Although not re commended, w ith a little patience and sandpaper, a useable tool may be formed from a piece of wood or plastic rod.
FT146 • 20 ❒ 8. Move your meter probe over to TP2, key the transmitter and adjust L5 and L11 for maximum negative read ing. Once aga in, go back and forth between th e two coils. You should get a reading of at least -120 mV. It is very important to tune for th e best peak as this will ensure proper transmitter operation.
FT146 • 21 transmitter keyi ng in a rece iver is of some help, but even the sim plest crystal oscillator can send a fi ne signal into your neighbor's receiver. Ideally, yo u have a small RF wattmeter, already inserted in the antenna line, capable of accurately measuring low outp ut power in watts.
FT146 • 22 Amateur radio magazines and handbooks provide a variety of circuits for RF wattmeters and relative field -strength indicators, including methods of using your VOM as an indicating device.
FT146 • 23 "hum-m-m-, that's not a .001 uf where a 100 pf should be is it?" If there is a problem in getting the m odulation working, a scope or audio amplifier will allow tracing down any pr oblem in sh ort orde r. The microphone audio is amplifier by about 350 times in U1:B.
FT146 • 24 Here's a handy reference chart for the 5 pin DIN jack PIN # FUNCTION 1 +12 VDC power input 2 Power ground 3 Audio input 4 Audio ground 5 PTT (Push-To-Talk) Audio level required is in the 10 to 50 mV range. PTT requ ires a path to ground of less than 10K ohm s.
FT146 • 25 NOTE ON REP LAC EME N T P ARTS : If you lose or damage parts during assembly or testing, you may, of course, order any needed replacement parts by writing or faxing the Ramsey Electronics, Inc. f actory. Som e of the more common parts m ay also be picked up at Radio Shack or other local parts distributors.
FT146 • 26 FT146 PARTS LAYOUT DIAGRAM.
FT146 • 27 The Ramsey K it Warranty Ple ase read caref ully BEF ORE cal ling or writ ing in about you r kit. Most prob lems can be solv ed w ithou t co ntac ting the fac tory. Notice that thi s is not a " fine print" warranty. W e w ant you to unders ta nd your ri ghts and o urs too ! All Ramsey kits w ill work if assemble d properly .
FT146 • 28 FT146 2 Meter FM Transmitter Kit Quick Reference Page Guide I ntroduc tion to t he FT146 .............. 4 Circuit Descri ption .......................... 5 Parts List ................ ........................ 6 FT146 Assembly Instru ctions .
Un punto importante, dopo l’acquisto del dispositivo (o anche prima di acquisto) è quello di leggere il manuale. Dobbiamo farlo per diversi motivi semplici:
Se non hai ancora comprato il Ramsey Electronics FT146 è un buon momento per familiarizzare con i dati di base del prodotto. Prime consultare le pagine iniziali del manuale d’uso, che si trova al di sopra. Dovresti trovare lì i dati tecnici più importanti del Ramsey Electronics FT146 - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso Ramsey Electronics FT146 imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul Ramsey Electronics FT146 ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il Ramsey Electronics FT146, ma non hai ancora letto il manuale d’uso, dovresti farlo per le ragioni sopra descritte. Saprai quindi se hai correttamente usato le funzioni disponibili, e se hai commesso errori che possono ridurre la durata di vita del Ramsey Electronics FT146.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il Ramsey Electronics FT146. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo Ramsey Electronics FT146 insieme con le istruzioni su come risolverli. Anche se non si riesci a risolvere il problema, il manuale d’uso ti mostrerà il percorso di ulteriori procedimenti – il contatto con il centro servizio clienti o il servizio più vicino.
