Vista 1 manual

M M o o d d e e l l 1 1 E E x x p p e e r r i i m m e e n n t t e e r r ’ ’ s s S S E E A A u u d d i i o o A A m m p p l l i i f f i i e e r r U U s s e e r r ’ ’ s s M M a a n n u u a a l l 500-0001MR4 http://audio.engineeringvista.com Rev. 4[...]

Dear Customer We at ENG Vista want to ta ke this opportunity to thank you for purchasing the Model 1 Experimenter’s SE Audio Amplifie r. The people that stand behind y our amplifier draw on more than a decade of professional electronics desi gn and manufacturing ex perience. We are committed to providing our customers with the hi gh quality sound[...]

SAFETY PRECAUTIONS IMPORTANT SAFEGUARDS PLEASE READ CAREFULLY ALL THE FOLLOWING IMPORTANT SAFEGUARDS THAT ARE APPLICABLE TO YOUR EQUIPMENT SAFETY 1. Read the User’s Manual and refer to it frequently during your experimenting. 2. Retain the User’s Manual for future reference. 3. All warnings should be strictly adhered to. 4. Follow instructions [...]

17. Unplug this product from the wall outlet befor e making any changes. Wait until tubes have cooled down. 18. When using replacement parts, be sure to use parts with sufficient voltage and power rating and adequate current carrying capability. 19. Should it become necessary to replace your tubes, remove the AC power plug from the wall and allow t[...]

GETTING STARTED The Model 1 amplifier kit was designed to provide: 1. a universal tube amplifier suitable for every day listening to the music from your PC or portable music source, or as a guitar amplifier easy to overdrive; 2. a headphone amplifier; 3. an amplifier for familiarizing with the s ound of Single Ended (SE) configuration; 4. a platfor[...]

ASSEMBLING THE KIT If you purchased an unassembled kit, you will have all the parts, including tubes and printed circuit board. Parts are in marked bags, with referenc e numbers and value written on a bag. Reference numbers are the ones printed on t he PCB, so locating parts positions should be very easy. PCB layout printout is also part of this do[...]

CONNECTIONS NOTE: Before you turn the amplifier on, make sure the speaker connections are properly hooked up, or that headphone selector switch is in the headphone position. Never run the amplifier without speakers or headphones, since this may damage transformers. When turning the unit on, make sure the volume control is at its lowest setting. ELE[...]

8 Vf PHONES Vf4b R82 220k/0.5W 202-0001 Vf4a C132 10u/350V 100-0001 R252 27R/2W 206-0002 R51 1k 200-0003 J102 161-0001 1 2 3 4 R290 0R N/A R22 *1k* 200-0001 Vf3a R201 *1k* 200-0003 C111 **220u/35V** 100-0002 R251 27R/2W 206-0002 R112 100R 200-0005 UL C72 1n/50V 100-0003 Vf2a C51 100n/250V 100-0006 J22 *RCA-WHITE* 160-0002 R52 1k 200-0003 OPT PRIM L[...]

BOARD LAYOUT AND DIMENSIONS: The following Figure shows the component layout and dimensions of the board (in mils – 1mil=0.001inch), mounting holes and locations of tubes, potentiometers, switch and headphone connector, as well as locations of input jacks. This should help builder with designing a fitting enclosure. Please always verify dimension[...]

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CONFIGURATION JUMPERS – MODE OF OPERATION: The Model 1 has four groups of jumpers intended for setting a mode of operation – Pentode mode (P), Ultralinear mode (UL) and Triode mode (T). Ultralinear mode can only be used with output transformer that have additional terminal for UL operation. Shorting blocks are inserted vertically so that t he d[...]

CONFIGURATION JUMPERS – NEGATIVE FEEDBACK SELECTION: The Model 1 has optional negative feedback connecti on provided by jumper J161 (J162) – FBK. By moving the shorting block horizontally across the two lower pins, the negative feedback will be engaged. The upper two pins are shorting block holders when feedback is not engaged. By using negativ[...]

CONNECTING POWER: As any other vacuum tube amplifier, Model 1 needs two voltages for proper operation: (1) Plate, or Anode voltage, Va and (2) Heater, or filament voltage Vf. Plate voltage should be brought to the terminal block J80 and filament voltage to J90. Pi cture below shows the layout detail with J80 and J90. Plate voltage (Va) should have [...]

CONNECTING OUTPUT TRANSFORMERS: For basic model, the output transformers should be designed to provide 5k Ω primary resistance. For the full pack, the primar y resistance should have 2.5k Ω rating. Rating of the secondary winding should correspond to the impedance of your speakers (4, 8 or 16 Ω , typically). There are many transformers in the[...]

Again, for best stereo image, they should be connected in phase. The second harmonic distortion is common with single ended amplifiers (i t gives them specific, rich sound), and air transports sound with some degree of the second harmonic distortion too. It is possible to notice change in sound and reduction in distortion just by swapping plus and [...]

UPSIDE - DOWN ASSEMBLY The Model 1 printed circuit board (PCB) was designed with top to bottom symmetry. This symmetry enables building a tube amplifier with “tube audio look”, where tubes are mounted on top of the chassis. All parts, except tube socke ts, can be mounted on the bottom of the board and soldered on the top side (top side is the o[...]

FINAL WORDS Once again, thank you for your purchase. We hope that the Model 1 will give you hours and hours of fun and have you experience a multitude of diffe rent qualities of the “tube sound”. Once you have exhausted all of the options, we hope that you will “retire” the amplifier from your bench into a nice chassis and have it rest on y[...]

PARTS LIST Parts with asterisks in the VALUE column are used in the Full-Pack assembly. Item Qty Reference EPN Value 1 2 R41, R42 N/U 2 14 R11, R12, R51, R52, R121, R122, R141, R142, R181, R182, R231, R232, R241, R242 200-0003 1k 3 8 R21, R22, R61, R62, R201, R202, R391, R392 200-0003 *1k* 4 2 R71, R72 202-0001 *220 k/0.5W* 5 2 R81, R82 202-0001 22[...]