Condition:New
Type:Logic ICs
Supply Voltage:220V
is_customized:Yes
Model Number:300B
This kit is a fever boutique, and the sound is very good.
No point cut design! Guarantee perfect standard sound quality under precision! 420V high anode voltage design, really good sound.
2.0mm * 185.4 * 286mm thick high quality immersion gold / lead tin blue printed circuit board
HIFI enthusiasts will eventually play tube amps. The ultimate tube player is 300B, and the DIY mill is the ultimate player. It is fun to transform the mill as you like.
After a long period of improvement and development, this circuit board has easy assembly and beautiful sound quality. And after 24 hours of continuous work thermal stability test. Waveform distortion test. 0 Low noise detection. Only for the convenience of users to reduce the trouble during the diy process. When installed, it will ring and test the voltage standard. 300B sound beautiful without additional rendering.
Features:
1. Standard circuit design, authentic classic 300B sound.
2.2.0mm high-quality immersion gold / lead tin blue printed circuit board (185.4 * 286.2mm), mechanical strength meets the requirements of fixed plug-in.
3.0 low-noise layout traces, almost no noise. The high heat dissipation design guarantees long-term stable operation even in a closed enclosure.
4. Multi-package component design, to meet the user's need to change the pitch volume of different size components.
5. The position of the screws and openings is beautiful and reasonable, which is convenient for diy chassis openings, and the integer opening size. Supplied with pcb 1: 1 cutout size chart.
6. The voltage of each test point has been marked to facilitate user debugging. (Almost soldered is OK, generally no debugging)
7. DC stabilized precision 5.0v filament power supply and bile rectification ensure the life of 300b.
8. This amplifier design can connect screen flow meter and VU meter head. Please consult the owner for details.
Common sense note:
1. The output transformer cannot be turned on without connecting the speaker, it will burn out under no load.
2. Electrolytic capacitors, diodes, rectifier bridges, voltage regulator chips, etc. need to pay attention to the direction of welding (refer to physical photos). Incorrect polarity can explode!
3. When the socket of the tube 300b is welded, the thick feet are in front (14 feet thick). Pay attention to the direction of the big octapod socket.
4. The input voltage should be connected to the terminal strictly according to the indication.
5. Don't get hot from the tube.
6. Filament balance is adjusted by 51R resistor or 100R potentiometer, choose one of them. Not both.
7. For safety reasons, it is recommended that you install the power supply into the fuse (1a). If you feel that it is not right, check the power immediately.
8. Power transformer 230v, 14v (for vu meter board) three wires are not used. Be insulated! The output transformer's super-linear tap G is insulated for nothing.
9. It is best to insert the 300b tube into the socket first, and then solder the socket to the circuit board.
The transformer parameters are as follows:
300B power transformer:
(Z11 EI 105 * 60MM)
Dip Lacquered Wire Output With Cover
400V-0-400V 0.2A
7.3V-0 3A
7.3V-0 3A
3.15V-0-3.15V 2A
5V 4A
1A for 14Vvu meter board
300B output transformer (pair):
(Z11 EI86 * 40MM)
Dipping wax wire output
Junior 3.5K
Secondary 0-4-8 Euro
300B inductance:
(Z11 EI76 * 40MM)
Dip Lacquered Wire Output With Cover
Inductance 10H
DC resistance 65 ohms
Tube:
300B / 4300B
6SN7 / 6N8P
5U4Z / 5Z3P
The components are visible! Choosing components is much better than most finished machines, worthy of 300b real sound!
