Instruction/ maintenance manual of the product SHA1 Ramsey Electronics
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SHA1 • 1 STEREO HEADPHONE AMPLIFIER Ramsey Electronics Model No. SHA1 Need a way to listen to line leve l audio from a tape deck or CD player? Need a way of boosting up any lo w level signal to earp.
SHA1 • 2 RA M SEY TRA NSMIT TER KIT S • FM100B Professional FM Stereo Transmitter • FM25B S ynthesized Stereo FM Transmi tter • MR6 Model Rocket Track ing Transmitter • TV6 Television Tr ans.
SHA1 • 3 STEREO HEADPHONE AMPLIFIER KIT Ramsey Publication No . MSHA1 Price $5.00 How does it work . ............ ....... 4 Assembly Strategy ................. 6 Parts List ........... .............. ....... 7 Parts Layout Diagram ............ 8 Part Values Diagram .
SHA1 • 4 What is it and how does it w ork? Let’s take a look at the schematic diagram, and we will follow through from input to output to get a general idea how this kit works, and why. W e will look onl y at the left channel circuitry starting at J1 since the right channel is ide ntical to the left.
SHA1 • 5 C3 is another coupl in g capacitor, and it serves the same purpose as C1 at the start of the circuit. This prevents the DC portion of the signal on the output of U1 fr om being sent to the earphones. VR1, C15 and C16 supply the regulated DC voltage for the circuit.
SHA1 • 6 RAMSEY “LEARN-AS-YOU-BUILD” ASSEM BLY STRATEGY Be sure to read through all of t he steps, and check the bo xes as you go to be sure you didn't mi ss any important steps. Althoug h you may be in a hurry to see re sults, before you switch on the power check all wiring and capacito rs for proper or ientation.
SHA1 • 7 SHA1 PARTS LIST Semiconductors 2 LM386 Audio Amplifier ICs (U1,2) 1 1N4002 rectifier diode (Bla ck body with white stripe on one end) (D1) 1 7808 Voltage Regulator (U3) Resistors 2 4.
SHA1 • 8 PARTS LAYOUT DI A GR AM.
SHA1 • 9 PA RT S VA LUE DIA GRA M.
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SHA1 • 12 AS S EM B L I NG T H E SH A1 H E AD P HO N E AMP L IF I E R S: Sort out all of your parts to begi n with, making sure you have all of the parts required.
SHA1 • 13 11. Install U2, one of the LM38 6 audio po wer amplifier ICs. Check the orientation of this ch ip to make sure the dot o r notch representing pin one is in the same direction as shown in the parts diagram. Make su re all eight pi ns are through the board before soldering.
SHA1 • 14 usually indicating the negative (-) terminal of the component. You will notice on the parts layout diagram that the hole for the positive terminal is denoted, not the negative one. You will want to install this component wi th the positive (+) lead in the same orientation as shown in th e parts layout diagram.
SHA1 • 15 35. Install C16, 10uF electrolytic capacitor. W atch polarity! 36. Install U3, the 7808 voltage regulator. You will want to bend the center lead out and orient the pa rt so that the writing on the front of the part faces the ou tside of the board.
SHA1 • 16 TESTING THE SHA1 You will need the following equipment for this test. Audio source such as signa l generator, C D player, or tape deck. RCA jacks to feed audio to the SHA1 Good quality headphones. A 9 volt battery or DC power supply Simply connect your SHA1 up as if you were going to use it.
SHA1 • 17 TROUBLESHOOTING TIPS PROBLEM: No sound out of any c hannel. SOLUTION: Use a DMM to check the power supply voltage, do you have a fresh batt ery? If everything is OK, check your assembly, especially your parts orientation (D1?). Also check your earphones for proper operati on as well as your sound source.
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SHA1 • 19 The Ramsey K it Warranty Ple ase r ead ca refully BEFO RE callin g or wr iting i n abou t y our kit. Most pr oblem s can be solv ed without contac ting the fac tory. Notice that thi s is not a "fine prin t " warranty . We want you to u nderstan d your righ ts and ours too ! All Ramsey kits will work if assembl ed properly.
SHA1 • 20 SHA1 STEREO HEADPHONE AMPLIFIER KIT Quick Reference Page Guide How does it work .......... ................. ... 4 Assembly Strategy .................. .......... 6 Parts L ist .................... ................. ...... 7 Parts Layout Diagram .
An important point after buying a device Ramsey Electronics SHA1 (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 SHA1 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 SHA1 - thus you can check whether the hardware meets your expectations. When delving into next pages of the user manual, Ramsey Electronics SHA1 you will learn all the available features of the product, as well as information on its operation. The information that you get Ramsey Electronics SHA1 will certainly help you make a decision on the purchase.
If you already are a holder of Ramsey Electronics SHA1, 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 SHA1.
However, one of the most important roles played by the user manual is to help in solving problems with Ramsey Electronics SHA1. Almost always you will find there Troubleshooting, which are the most frequently occurring failures and malfunctions of the device Ramsey Electronics SHA1 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
