stuart, did you hook up both channels yet? coz i only get hum when both are hooked up. so it looks like ground loop problem. which is strange coz i hacked my boards and chips out of a home stereo.. transformer and all the other stuff i needed. what are you using for volume? a pot infront of the amp or on the pre/mixer? see you soon, steve.. ..
strangely quiet
Steve,
The 4040xi modules I'm using are mono, so while I have hooked up 2 channels, the fact that they are silent may be meaningless as a comparison to the situation you have.
With repect to volume setting, the CD walkman I use for test purposes has a volume control on it's headphone output, so currently I use that. Ultimately the low pass crossover for the sub will incorporate the level setting pots.
Stuart
Steve,
The 4040xi modules I'm using are mono, so while I have hooked up 2 channels, the fact that they are silent may be meaningless as a comparison to the situation you have.
With repect to volume setting, the CD walkman I use for test purposes has a volume control on it's headphone output, so currently I use that. Ultimately the low pass crossover for the sub will incorporate the level setting pots.
Stuart
ok now ive gone and done it, even hooking up one channel gives huge hum, touching the input sends the amp mad.
if i put things back and go the other way maybee all will be quiet? lets hope.. c you soon, steve.. ..
if i put things back and go the other way maybee all will be quiet? lets hope.. c you soon, steve.. ..
im using a portable stereo, headphone socket to twin phono for testing, using the volume on the stereo, similar to you stuart. and DOHHH, i thought those boards looked small, i wasnt paying attention to which chip you where using. hadnt realised they where the mono chips. QUESTION, does any one know how to make output choke coils? i know they are just enameled wire, but how thick and how many turns for a given value??
deja vu, all over again
Steve,
as morbid suggests, you can wind heavy enameled copper wire around the body of the output resistor. By heavy I mean 16 gauge, 0.5mm or thicker. The number of turns is probably dependant on what the resistor is constructed of, but 10-20 turns is easy enough. The inductor is supposed to be a very low impedance, like a dead short at audio freq...
The car amp I dismantled didnt have them at all, consequently, neither does the sub-amp...of course I can pretty much guarantee the load on the sub-amp will be 'safe'.
Morbid found the output resistor might be too small at 2w, but most amps seem to use 2-5w, though some big old adcom amps I just fixed had huge 10w ceramic wirewounds.
Good luck
Stuart
Steve,
as morbid suggests, you can wind heavy enameled copper wire around the body of the output resistor. By heavy I mean 16 gauge, 0.5mm or thicker. The number of turns is probably dependant on what the resistor is constructed of, but 10-20 turns is easy enough. The inductor is supposed to be a very low impedance, like a dead short at audio freq...
The car amp I dismantled didnt have them at all, consequently, neither does the sub-amp...of course I can pretty much guarantee the load on the sub-amp will be 'safe'.
Morbid found the output resistor might be too small at 2w, but most amps seem to use 2-5w, though some big old adcom amps I just fixed had huge 10w ceramic wirewounds.
Good luck
Stuart
i give up, im gona take everything of the board and either try and make some boards using that stick and peel stuff, it is quite a simple board. OR have a go at building it on strip board. ive just got another home hifi free and its got an stk4181v so ive got another to play with. if the board works i may aproach a local firm to get a few made for the higher wattage chips. thanks for the help so far guys, steve.. ..
p.s.
how you doing morpheus82? hope you have not been put off this chip, let me know how you get on, and ill do the same, coz even if we use different chips, most of the range is pin compatable. where you thinking of getting a board made? or D.I.Y. ? see you soon, steve.. ..
how you doing morpheus82? hope you have not been put off this chip, let me know how you get on, and ill do the same, coz even if we use different chips, most of the range is pin compatable. where you thinking of getting a board made? or D.I.Y. ? see you soon, steve.. ..
i just have to mention....
i changed the output resistor into 5W and if he's gonna burn gonna raise to 9W..
the resistors Wattages from the schematics are the Minimum i took for my circuit...
he rated the output for ~320 W / 75V / 4ohm load
i use 30 (27V onload stable) / 60-80Watts / 16ohm load
i changed the output resistor into 5W and if he's gonna burn gonna raise to 9W..
the resistors Wattages from the schematics are the Minimum i took for my circuit...
he rated the output for ~320 W / 75V / 4ohm load
i use 30 (27V onload stable) / 60-80Watts / 16ohm load
Attachments
still thinking...
university courses began monday...so i don't have so much time now...otherwise i'm still thinking...If the max power at 8 ohms is 100wrms, this means that the chip will deliver 5A max with a good thd, and this means only 50Wrms for a 4 ohms!!!
not good...so I'm thinking to use a 4050...opinions?
university courses began monday...so i don't have so much time now...otherwise i'm still thinking...If the max power at 8 ohms is 100wrms, this means that the chip will deliver 5A max with a good thd, and this means only 50Wrms for a 4 ohms!!!
not good...so I'm thinking to use a 4050...opinions?
alternatives...
Hi,
I have an old sanyo catalog, looking through all the offerings it seems that while they have a broad range of power outputs, the maximum current is always in the range of 4-5 amp per output transistor. This would seem to limit your choices, the stk4050 seems like overkill, but should work fine, and is the only part I could find that would be within spec at 100w into 4 ohms.
The STK401 family is mostly designed to work into 6 and 3 ohm loads, the highest output members limited to 6 ohms. You might also consider the stk401-340, it offers 2 channels of 120w/6ohms, which is closer to your needs, it is rated at +-51v, you might want to lower this to keep the power dissipation within reasonable limits. It will do 80w into 4 ohms within spec, and everything I've seen suggests these are conservatively rated parts. Just make sure you have a big heatsink if you plan to use it all...
Stuart
Hi,
I have an old sanyo catalog, looking through all the offerings it seems that while they have a broad range of power outputs, the maximum current is always in the range of 4-5 amp per output transistor. This would seem to limit your choices, the stk4050 seems like overkill, but should work fine, and is the only part I could find that would be within spec at 100w into 4 ohms.
The STK401 family is mostly designed to work into 6 and 3 ohm loads, the highest output members limited to 6 ohms. You might also consider the stk401-340, it offers 2 channels of 120w/6ohms, which is closer to your needs, it is rated at +-51v, you might want to lower this to keep the power dissipation within reasonable limits. It will do 80w into 4 ohms within spec, and everything I've seen suggests these are conservatively rated parts. Just make sure you have a big heatsink if you plan to use it all...
Stuart
dual mono...
thanx stuart, but my idea is to realize a dual mono, so to use 1 toroid for left, and one for right, so I can't use a stereo amplifier...(damn, it will cost less!!)This means that I must use the 4050...but i've seen a 4060 and a 4065...do you know anything?or...do anybody know anything???
thanx stuart, but my idea is to realize a dual mono, so to use 1 toroid for left, and one for right, so I can't use a stereo amplifier...(damn, it will cost less!!)This means that I must use the 4050...but i've seen a 4060 and a 4065...do you know anything?or...do anybody know anything???
parts...
Hi,
4065 is 25+25w for car audio applicatiobs, and I don't think its what you want.
4067 is a another special for car amps, rated to drive 50w into 1 ohm.
Can't find anything on the 4060, other than it has been discontinued, so you'll need to check with your supplier for datasheets, availability etc. I should add the official status of the 4050ii/v is discontinued...
You probably already spotted this, but if you end up buying it, and you care about specifications, you might want to make sure you get the 4050v, not 4050ii, the latter has 0.4% distortion, the former 0.08%. If Sanyo has released one the 4050x or 4050xi would probably be better again, since every other part in the series is 0.008%...
Another part that might work for you is the stk404-140, it is rated to put 180w into 6ohms, with lots of distortion, but obviously the current capability is there or it would be smoked. Plus this part has a simpler application circuit, you could build it on the pins of the device. Plus this is shown as available...
Stuart
Hi,
4065 is 25+25w for car audio applicatiobs, and I don't think its what you want.
4067 is a another special for car amps, rated to drive 50w into 1 ohm.
Can't find anything on the 4060, other than it has been discontinued, so you'll need to check with your supplier for datasheets, availability etc. I should add the official status of the 4050ii/v is discontinued...
You probably already spotted this, but if you end up buying it, and you care about specifications, you might want to make sure you get the 4050v, not 4050ii, the latter has 0.4% distortion, the former 0.08%. If Sanyo has released one the 4050x or 4050xi would probably be better again, since every other part in the series is 0.008%...
Another part that might work for you is the stk404-140, it is rated to put 180w into 6ohms, with lots of distortion, but obviously the current capability is there or it would be smoked. Plus this part has a simpler application circuit, you could build it on the pins of the device. Plus this is shown as available...
Stuart
Hello,
I'm going to build an amplifier on STK4241V. It will be a 4 channel (2xSTK4241V) 150W@4 Ohm load. It should work fine..
But problem is, that I don't know where to connect 8th pin.
I do not need that muting or other protections. Or maybe I can leave that 8th pin to "hang on air" and simply connect 6th pin to -Vcc?
Thank you for your answers😉
P.S. I'm sorry for my english.
I'm going to build an amplifier on STK4241V. It will be a 4 channel (2xSTK4241V) 150W@4 Ohm load. It should work fine..
But problem is, that I don't know where to connect 8th pin.
I do not need that muting or other protections. Or maybe I can leave that 8th pin to "hang on air" and simply connect 6th pin to -Vcc?
Thank you for your answers😉
P.S. I'm sorry for my english.
morpheus82
Just because cars have DC power. So why will a manufacturer make a 60Hz inverter and a BIG transformer ? The cheaper and better is make an SMPS. ALL car amplifiers have SMPS, except those "boosters".
Just because cars have DC power. So why will a manufacturer make a 60Hz inverter and a BIG transformer ? The cheaper and better is make an SMPS. ALL car amplifiers have SMPS, except those "boosters".
ohms law
Hi
The data sheet is needed so you know the working voltage range of and thin film package.
After that remember ohms law always applies
http://www.the12volt.com/ohm/ohmslaw.asp
check out the link
Dave
Hi
The data sheet is needed so you know the working voltage range of and thin film package.
After that remember ohms law always applies
http://www.the12volt.com/ohm/ohmslaw.asp
check out the link
Dave
Hello, does anyone know if the new STK4241 Mark 5 amplifier chips are pin compatible with the STK4241 Mark 2 ("II") ??
Can the new ones be used in order to repair on older amplifier with STK4241 chip?
Can the new ones be used in order to repair on older amplifier with STK4241 chip?