Hello to everyone, this is my first post 
Unfortunately it brings some sad news....and it was all going so well.....
I got a lovely 4780 kit from Peter Daniel and set about making a small stereo amp as my first ever DIY project.
Having spent the past few days putting the kit together, it was ready for testing today. Well, it worked.....first time. I was well chuffed and then whilst checking the voltages on one of the boards i must have shorted the rails with a probe lead....my stereo has become a mono ! So frustrating! Guess i'll just have to get hold of another chip....other components look to be ok, so with any luck i can swap the chip out and all will be well.
Whilst I've got all of your attention, I might as well ask...At the moment I have no power switch and sometimes, when plugging in, the 1.6A time delay fuses I'm using blow. Sometimes they don't however...
Using a 300VA Transformer with 25V twin secondaries.
Anyone shed any light on this? Is it just to do with current inrush at power on (i.e. do i need some bigger/longer time delay fuses)? I'm not using any Ci caps or input caps at the mo.
Unfortunately it brings some sad news....and it was all going so well.....
I got a lovely 4780 kit from Peter Daniel and set about making a small stereo amp as my first ever DIY project.
Having spent the past few days putting the kit together, it was ready for testing today. Well, it worked.....first time. I was well chuffed and then whilst checking the voltages on one of the boards i must have shorted the rails with a probe lead....my stereo has become a mono
! So frustrating! Guess i'll just have to get hold of another chip....other components look to be ok, so with any luck i can swap the chip out and all will be well.Whilst I've got all of your attention, I might as well ask...At the moment I have no power switch and sometimes, when plugging in, the 1.6A time delay fuses I'm using blow. Sometimes they don't however...
Using a 300VA Transformer with 25V twin secondaries.
Anyone shed any light on this? Is it just to do with current inrush at power on (i.e. do i need some bigger/longer time delay fuses)? I'm not using any Ci caps or input caps at the mo.
Many thanks for the reply. It was my own silly fault...standard safe procedure went out the window in a flurry of excitement
Peter Daniel: How much to get a replacement lm4780 from you with shipping to the UK? I'm gonna be stung by big handling fees etc to order in the UK.
If anyone is putting in a Farnell/Digikey order and could help me out here I'd be eternally grateful.
Peter Daniel: How much to get a replacement lm4780 from you with shipping to the UK? I'm gonna be stung by big handling fees etc to order in the UK.
If anyone is putting in a Farnell/Digikey order and could help me out here I'd be eternally grateful.
in the , I figure I can just wait for a new one.
Hi rs1026,
if you have lots of the lm4780, i would order some of these pots:
http://www1.jaycarelectronics.com/p...&pageNumber=&priceMin=&priceMax=&SUBCATID=802
they seem to get the new standard in audio-devices...
BTW for an amp i would prefer logarithmic ones...
So: i'm interested in 2 chips... drop me a line, please
Michael
if you have lots of the lm4780, i would order some of these pots:
http://www1.jaycarelectronics.com/p...&pageNumber=&priceMin=&priceMax=&SUBCATID=802
they seem to get the new standard in audio-devices...
BTW for an amp i would prefer logarithmic ones...
So: i'm interested in 2 chips... drop me a line, please
Michael
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