Nah, some di*k put the led's in reverse. Need to order more IRF510's. Need to diagnose what else may have been damaged :-(
Correcting the LEDs may not have caused any further damage.
Mine had track shorts around the LEDs and, once corrected everything was fine.
Mine had track shorts around the LEDs and, once corrected everything was fine.
yup
LED CCS , without other current path , tried to fill their gates with 3-5mA , and pull them all way up
so - they go poof because of excessive Ugs , not because of excessive current
LED CCS , without other current path , tried to fill their gates with 3-5mA , and pull them all way up
so - they go poof because of excessive Ugs , not because of excessive current
How hard are these to match, if I buy 10 should I get two matched pairs if from the same batch or is it a bit more variable than this. Everything else looks ok I think.
10 will suffice , considering that those are for CCS load duty ;
just for fact - upper ones (9510) are more important , matching wise
just for fact - upper ones (9510) are more important , matching wise
I put some IRF840's in and the unit test's fine(very brief test). I have 15 IRF610's coming from an Aussie eBay dealer so hopefully they will come within a few days.
All i need now is a pot, I am thinking could I use part of the lighternote I have currently in use? One concern is the minimun volume setting as I am building 110db sensitive horns?
All i need now is a pot, I am thinking could I use part of the lighternote I have currently in use? One concern is the minimun volume setting as I am building 110db sensitive horns?
?Not sure, I am not that smart or knowledgable, still learning.
Amp's are Aleph J's which are nearly finished.
Out of interest the complete system will be as follows
Diy Slate and acrylic TT
http://www.diyaudio.com/forums/analogue-source/168284-my-tt-build-3.html
Dl103R Cart
HPS 5.1 Phono
http://www.diyaudio.com/forums/analogue-source/167360-hps-5-1-a.html
Pumpkin
Aleph J's
4 Way horns
Fane 8m, 200hz LeCleach
Yamaha 6681b 400hz LeCleach
Fostex T500A MKII
Bass TBA
I hope to avoid digital X-Over so am looking at Passive line level for X-Over.
Amp's are Aleph J's which are nearly finished.
Out of interest the complete system will be as follows
Diy Slate and acrylic TT
http://www.diyaudio.com/forums/analogue-source/168284-my-tt-build-3.html
Dl103R Cart
HPS 5.1 Phono
http://www.diyaudio.com/forums/analogue-source/167360-hps-5-1-a.html
Pumpkin
Aleph J's
4 Way horns
Fane 8m, 200hz LeCleach
Yamaha 6681b 400hz LeCleach
Fostex T500A MKII
Bass TBA
I hope to avoid digital X-Over so am looking at Passive line level for X-Over.
My skills are best used on the hands on building part. The technical side is where I am laccking and slowly learning.
So what gain should I set Pumpkin to and how do I go about working this out.
Cheers
set Pumpie for - say - 4x gain
meaning - input resistors in range of 15K , feedback resistors in range of 62K-68K
meaning - input resistors in range of 15K , feedback resistors in range of 62K-68K
Hi Andy and good year !Please why did you use that connection between the heatsink and chassis? You've got yourself a problem of background noise initially? It seems to me that by touching with my hands sinks the noise varies, please could you give me some advice?
Thanks in advance
Antonio.
What is the preferred front-end (voltage gain stage) for a single-ended F4?
I am looking at the BA3 FE, Pumpkin, Blowtorch, and various opamps. The difficulty is getting enough voltage swing and a voltage gain of 6x or better with low distortion, particularly higher order harmonics.
I am looking at the BA3 FE, Pumpkin, Blowtorch, and various opamps. The difficulty is getting enough voltage swing and a voltage gain of 6x or better with low distortion, particularly higher order harmonics.