anyone knows about lanzar 50?

[swedude]

i got one lanzar 50 and i cant find any info for it on the net.its a tiny amp that measure about 225x120x65mm in chassie. Power section is tl594 and irfz44 and the audiopart is tip142/147.its totally dead.

 

[Perry Babin]

If no one answers your question, post a photo of the board.

 

[swedude]

ok perry i do that later and try to get a good one with macro.

 

[swedude]

maby off topic, but how big pict in kb/mb is allowed.i dont want to be kicked out

 

[Perry Babin]

It won't allow you to load a photo that's too large if you use the 'go advanced' button and load from your hard drive.

 

[swedude]

here some photos

 

[Perry Babin]

Did you remove the missing IC?

 

[swedude]

yes im going to replace it.i Think i did it earlier but a 494 instead of 594 that it says on the label.the amp did,n start at all.i have to Clean up in the hobbie room so i can use the scope to see if the pwm have signal after fitting the new ic.do you Think i can use a ic holder between or will it do more trouble.?

 

[Perry Babin]

Unless this has to be repaired immediately, why not wait for the correct part?

 

[swedude]

well no one of the things have to fixed immediatley coure its all mine,but like try to fix anyway so i can sort out all stuff that not can be fixed.but the question on this one is ,can i have a socket for esier put out to measuring and find leads for trouble shooting,or will it do more harm then less.

 

[Perry Babin]

As long as there are no damaged vias, you can use a socket. If there are damaged vias, a socket may make troubleshooting more difficult. Before installing anything in that location, take a good quality photo of all of the traces under the IC so that you can confirm various connections if there are problems.

 

[swedude]

is vias the same as the bridge in the holes between under and over the traces/leads?

 

[Perry Babin]

Yes:
https://en.wikipedia.org/wiki/Via_(electronics)

 

[swedude]

thanks.one of my problems is that i not to good at English specially Tech Words.its been along time since i was in shool.(besides some short electrical installation shool 10 years ago) and a also a Swedish ,so English not my first laung,, i guess you did,nt graduate yesterday eighter.lol. so you maby know about memory problems. but u a grate persion i think

 

[swedude]

now i have put in the tl594(without socket) and its Power up.but z44,s goes hot fast and protection led lights,not Power led.amp take just above 3A in idle.no signals on input.utput 250mv and Rising on both channels.do the protection led is for output or Power section or both?

 

[Perry Babin]

Were the original FETs IRFZ44s?

What is the value of the gate resistors for the Z44s?

 

[swedude]

yes its irfz44n.s not 100% sure if they are orginals. course the dont look the same. the text is different and one is more smooth Surface backside.the gate resistors seems to be 91 ohm (White,brown,black.)and reads 93,2 ohms and 89,8 ohms for the other one i found some info on the board,lz60/1 and rev g.it has to be the boards name and version.maby i can test put in 2 new z44 rhat look the same,i think i got many of them home.

 

[swedude]

i just putted in new 44,s but no luck.stilL same problem.i just checked voltage to outputs(tip 142/127) and i dont have more than 06-1,5 volts.(fast measure corse 44s get hot fast)

 

[Perry Babin]

What is the DC voltage on pins 9 and 10 of the 494?

What is the DC voltage on the gate legs of the power supply ICs?

Clamp the FETs to the heatsink if they're at risk of failing.

 

[swedude]

its difficult to have it in the heatsink due to the Construction,so i use isolated plates for heatsink,otherways i cant do measuring if use original heatsink.because it will cover to mutch of card..voltage is about 1,82v both for pin9 and 10 om tl594 and the same on gates on 44.s