Kenwood KA-3750 .. for 15 brittish pounds
That is no bad buy, in my opinion.
The only thing I know about Kenwood,
is that they make/made some real good amplifiers for reasonable money.
you can do a lot worse than Kenwood, if thinking commercial amplifiers.
Unfprtunately my own Kenwood KA-7100
a very good machine!!!!,
has got one broken output transistor. (I made that shorcut blow out myself )
I will try fix that one.
And it will work well again
That is no bad buy, in my opinion.
The only thing I know about Kenwood,
is that they make/made some real good amplifiers for reasonable money.
you can do a lot worse than Kenwood, if thinking commercial amplifiers.
Unfprtunately my own Kenwood KA-7100
a very good machine!!!!,has got one broken output transistor. (I made that shorcut blow out myself
)I will try fix that one.
And it will work well again
Yeah i know i got a great buy. Time like this it costs 10 to 15 pounds to just have a good meal. So do you think it the transissters that is blown on one channel which why it sounds disorted still waiting to receive the amp then i can explain the problem accurately.
kenwood ka-3750
http://cgi.ebay.co.uk/ws/eBayISAPI....m=250280016535&ssPageName=STRK:MEWN:IT&ih=015
kenwood ka-3750
http://cgi.ebay.co.uk/ws/eBayISAPI....m=250280016535&ssPageName=STRK:MEWN:IT&ih=015
no
if some transistor is blown
there are worse things than distortion (like total silence )
I would start with check out Big Power Supply filter caps.
They may be too old to give any capacitance (at least enough for filtering).
Then I would see if the Volume Potentiometer (either channel) is worn out.
Somtimes can be a worn out carbon pot
that has bad contact surface for the wiper.
Switches can be worn out, with bad contact surfaces.
if some transistor is blown
there are worse things than distortion (like total silence
)I would start with check out Big Power Supply filter caps.
They may be too old to give any capacitance (at least enough for filtering).
Then I would see if the Volume Potentiometer (either channel) is worn out.
Somtimes can be a worn out carbon pot
that has bad contact surface for the wiper.
Switches can be worn out, with bad contact surfaces.
Thanks for the input if the caps are bad on the power supply i will change them for alternatives obvoulsy same value. I got some ncie 80vdc 6800uf caps i wonder which ones will be in the kenwood. Switches are no problem i just re-solder the joints and if they still faulty i got some spare ones from a broken amp which yet to receive its new pcb the gainclone.
just recived my book from the postman - high power audio amplfiier construction manual by g.randy slone. he suggests 10 percent higher voltage for resovair caps than actual output of the power transformer rating for safety margin, most people use double voltage cap per rail than actual power transformer output. exmple per raild is 30 volts use 40 volt cap per rail recomneded by g slone. most people use double 30 volts power output and 60 volt caps. I think i finally learning something. sorry about spelling mistakes it's the keyboard layout.
I have now uploaded a video of the actual kenwood 3750 in action all cleaned imporved sound but one bad channel still exists - please do watch the video it is two minutes long Thank you.
http://www.youtube.com/watch?v=D_YjQTvw4Hg
http://www.youtube.com/watch?v=D_YjQTvw4Hg
I just watch & listened to your video.
Yes, I think this is one bad transistor in that channel.
Not necessarily one big power transistor at heatsink.
If is not actually broken/damaged transistor, so it is a bad joint somewhere.
Can be solder joint.
Can also be some wire, that have only very little or bad contact
and so can not deliver enough current to some transistor.
You just have to try to measure voltage with multimeter and try to track down this problem.
Be careful when measure with Probes and powered on circuit
I have made shortcut burn outs with my probes .. several times
Yes, I think this is one bad transistor in that channel.
Not necessarily one big power transistor at heatsink.
If is not actually broken/damaged transistor, so it is a bad joint somewhere.
Can be solder joint.
Can also be some wire, that have only very little or bad contact
and so can not deliver enough current to some transistor.
You just have to try to measure voltage with multimeter and try to track down this problem.
Be careful when measure with Probes and powered on circuit
I have made shortcut burn outs with my probes .. several times
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