Dear All,
Any body have experienced: http://4.bp.blogspot.com/-blvgw5ntF...1600/Rangkaian+Amplifier+Blazer+1000+watt.jpg
about Blazer 500 or Blazer 1000 watt.
Any body have experienced: http://4.bp.blogspot.com/-blvgw5ntF...1600/Rangkaian+Amplifier+Blazer+1000+watt.jpg
about Blazer 500 or Blazer 1000 watt.
Blazer is a very common amplifier module in my country. Mainly used for outdoor amp (PA). Probably the most reliable, especially when the bias is set low. But the schematic in your link is wrong.
Blazer 500
I built a Blazer 300 a couple of years ago. Purchased off of Ebay. Boards were preassembled with bias already set. I posted pictures on this forum. I have been extremely pleased with this amp. With 56 volt rails, it is very powerful.
I built a Blazer 300 a couple of years ago. Purchased off of Ebay. Boards were preassembled with bias already set. I posted pictures on this forum. I have been extremely pleased with this amp. With 56 volt rails, it is very powerful.
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Sir can u share its details ..
Sir can u share its details e.g. its schematic ..pcb etc ..so that I could enjoy..
Sir can u share its details e.g. its schematic ..pcb etc ..so that I could enjoy..
I'm not sure about component values, but the schematics seems okay except for the 15v zener that shouldn't be connected to the input.
See this 300W version for the correct connection of the 15v zener.
Attachments
Sir,
I have tried 3, 4 amps since yet, but this amp attracted me with the name of Peavey. and its cascading is also similar e.g. both get speaker output from collectors 😉.
Gents a I have also a great Amp in my lab may be some of you would be familiar with its name, TP 100 or HH 100 made by england. Simple 4 n channel transistors at power stage. Please share its schematic if u people have this.
The 1000W version? I cannot confirm that the values are correct as I don't have the exact schematic that I have built. The 300W version was simulated correctly and it was drawn based on schematics that I have built many times (and I have many of the PCBs).
But you can browse the net to find similar schematics along with someone who claimed has built the amp based on that schematic.
Nothing special about this amp (other than reliability for PA use) so why not choose a much better and completely documented project (along with PCB design etc). You can search for "Honey Badger" in the sticky section of solid state forum if you need low wattage one.
There are thousands of amps out there. Why waste time building everything. Pick some good ones. Probably the best ones.
Amps like this are pretty tolerance with part substitution.
V11, it's a simulated voltage source required for analysis, but you don't need to build that. Assume it is a straight line.
VR2K and R16 represents a potentiometer (trimmer) to adjust the bias current. In implementation I rarely use trimmer. I prefer using 2 fixed resistors.
Hi Kamran, yes, you have to connect both ends of V11.
A trimmer has 3 legs. It is like connecting 2 resistors so the middle point is one leg, and each transistor's end, which is not connected, is the other leg(s).
But you should know how to set the bias, otherwise you may run too much bias current and blow the transistors. Later at home I will post a picture so you will know how to add another resistor to avoid this problem.
If you use 2 resistors as represented by VR2K and R16, which are 1k1 and 0k9 then the bias is fixed but you may not be able to find resistors with those values...
For the PCB, I have only empty ones (no assembled ones) as I don't build amps of this quality (I use the PCB to build other amps, mostly with similar schematic, such as the Goldmund Mimesis).
But if you google "blazer amplifier pcb" you will get at first hit exactly the pcb that I have (point7electronics.wordpress.com).
EDIT: I think I don't need to show you how to add the extra resistor for biasing, as you can see clearly from the googled image.
ADD: I think you can consult that website (may be I know the owner, from the stuff they post). I own all the PCBs displayed in my google search from that web so I know they work. I don't know if they publish the schematic or not.
A trimmer has 3 legs. It is like connecting 2 resistors so the middle point is one leg, and each transistor's end, which is not connected, is the other leg(s).
But you should know how to set the bias, otherwise you may run too much bias current and blow the transistors. Later at home I will post a picture so you will know how to add another resistor to avoid this problem.
If you use 2 resistors as represented by VR2K and R16, which are 1k1 and 0k9 then the bias is fixed but you may not be able to find resistors with those values...
For the PCB, I have only empty ones (no assembled ones) as I don't build amps of this quality (I use the PCB to build other amps, mostly with similar schematic, such as the Goldmund Mimesis).
But if you google "blazer amplifier pcb" you will get at first hit exactly the pcb that I have (point7electronics.wordpress.com).
EDIT: I think I don't need to show you how to add the extra resistor for biasing, as you can see clearly from the googled image.
ADD: I think you can consult that website (may be I know the owner, from the stuff they post). I own all the PCBs displayed in my google search from that web so I know they work. I don't know if they publish the schematic or not.
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Respected Sir,
I can adjust the bias with trimmer (Normally base volts adjusted on the base and collectors of power transistors) , but i need 1 clarification that do we need to adjust the biase on empty or zero load or on the recommended load. because the biase change when we connect speakers with the amp.
I can adjust the bias with trimmer (Normally base volts adjusted on the base and collectors of power transistors) , but i need 1 clarification that do we need to adjust the biase on empty or zero load or on the recommended load. because the biase change when we connect speakers with the amp.
Basically you need maximum resistance between BASE and EMITTER of the Vbe transistor, to set the output bias current at minimum. So if you use 4k7 trimmer, 4k7 between base and emitter AND 0k between base and collector.
Of course the real bias is with the real load. But I think the difference is not big. I always did it without load because this bias accuracy is not so important for me. For example, with no load it could be 54mA and with 2 Ohm load it could be 56mA. For me, even 60mA or 70mA is not a big deal.
But MAY BE in different schematics or situations the difference is higher than that, I don't know.
I may use wrong terminology, but when I said "output bias current" it means the current through collector or emitter of the output transistor. Because this specific amp has resistor at the emitter of the output transistor (0.22 Ohm), it is possible to measure current through it by measuring voltage drop across the resistor (I=V/R).
Hopefully you're not confusing output transistor (the biggest ones) with Vbe transistor (the one near the trimmer/variable resistor, on the schematic, but often positioned near output transistor in order to sense the temperature of the output transistor)
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