Ramsey Electronics PR40 Guide de dépannage

PR40—1 440 Mhz LOW NOISE PREAMP KIT • 10 db Gain, 1 db Noise Figure • Runs on 9 to 15 VDC • Hi-Q tuned input to reduce overload • Small size to fit in

PR40—10 PR40 ON-OFF SWITCHING SUGGESTION Depending on your particular application and intended frequency, you may wish to use a DPDT power switch wit

PR40—11 A 440 Mhz “ACTIVE ANTENNA” For situations where a simple indoor receiving antenna is needed, the PR40 preamp will add considerably improved p

PR40—12 2SC2498 CHARACTERISTICS: The 2SC2498 transistor is a bipolar silicon NPN low noise UHF/VHF amplifier in a TO-92 case, suitable for service

PR40—13 TROUBLESHOOTING GUIDE The only possible causes for malfunction of the PR40 are faulty or incorrectly installed parts. Recheck your work. Tran

PR40—14 THE RAMSEY PR2: THE ULTIMATE BROADBAND PREAMPLIFIER After you find out how practical a well-built PR40 can be for 440MHz operating, you will

PR40—15 The Ramsey Kit Warranty Please read carefully BEFORE calling or writing in about your kit. Most problems can be solved without contacting the

PR40—16 Published by Ramsey Electronics, Inc. Copyright 1994 All rights reserved. Ramsey Electronics, Inc. 590 Fishers Station Drive Victor, NY 14564

PR40—2 INTRODUCTION TO THE PR40 LOW NOISE PREAMPLIFIER A “preamplifier” gives an initial boost, measured in decibels, to the level of a signal be

PR40—3 CIRCUIT DESCRIPTION L1 and C2 form a tuned input filter for the preamp to reject out-of-band signals. The 3 db bandwidth of this filter is 24M

PR40—4 PARTS SUPPLIED WITH PR40 KIT CAPACITORS  2 2 or 2.2pF disc capacitor (C1,2)  2 4.7 or 5pF disc capacitor (C3,6)  1 100pF disc capacit

PR40—5 RAMSEY PR40 PRE-AMP PARTS LAYOUT DISREGARDHOLESNOTE: Bend over L1 lead after installingto connect the two PC traces togetherFOR MOUNTINGSCREW

PR40—6 PR40 PRE-AMP ASSEMBLY PROCEDURE Soldering 10 parts to a PC board is not a big job, but good performance of the PR40 requires attention to kee

PR40—7  3. Install C4, 100pF (marked 100 or 101).  4. Install C5, .01uF (marked .01 or 103 or 10nF). Disc capacitor C5 is the bypass capacit

PR40—8 PROGRESS SUMMARY: The wiring of your Ramsey PR series preamp PC board is now complete. It will take you less than a minute to completely reche

PR40—9 TESTING AND ADJUSTMENT With your preamp installed between antenna and receiver, the only adjustment needed is the obvious one: peaking L1 for